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Tarkan, Haci Mustafa. "Air-assisted solvent extraction." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102735.
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Air-Assisted Solvent Extraction (AASX) is a novel concept that uses a solvent-coated bubble to contact the organic and aqueous phases. The advantages over conventional solvent extraction (SX) are high solvent to aqueous contact area with reduced solvent volume and ease of phase separation due to the buoyancy imparted by the air core. This opens the way to treat dilute solutions (<1 g/L), such as effluents.The novel contribution in this thesis is the production of solvent-coated bubbles by exploiting foaming properties of kerosene-based solvents.
The basic set-up is a chamber to generate foam which is injected through a capillary (orifice diameter 2.5 mm) to produce solvent-coated bubbles (ca. 4.4 mm) which release into the aqueous phase. This generates a solvent specific surface area of ca. 3000 cm-1, equivalent to solvent droplets of ca. 20 mum. Demonstrating the process on dilute Cu solutions (down to 25 mg/L), high aqueous/organic ratios (ca. 75:1) and extractions are achieved. The solvent readily disengages to accumulate at the surface of the aqueous solution.
The LIX family of extractants imparts some foaming to kerosene based solvents but D2EHPA does not. An extensive experimental program determined that 1.5 ppm silicone oil provided the necessary foaming action without affecting extraction or stripping efficiency, greatly expanding the range of solvents that can be used in AASX.
To complement the foam study, films on bubbles blown in solvent were examined by interferometry (film thickness) and infra-red spectroscopy (film composition). A "bound" solvent layer was identified with an initial thickness of ca. 2 - 4 mum, comparable to that determined indirectly (by counting bubbles in an AASX trial and measuring solvent consumption). The film composition appeared to be independent of film thickness as it decreased with time.
As a start to scaling up, the single bubble generation system was adapted by installing up to 8 horizontal capillaries. The bubbles generated were ca. 3.4 mm. Trials showed the multi-bubble set up was a simple replication of the individual bubble case. Preliminary analysis of kinetic data shows a fit to a first-order model.
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Langlais, Joseph. "Strontium extraction by aluminothermic reduction." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22447.
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The Melt-Leach-Evaporation (MLE) process is under development for the extraction of valuable Group IA or IIA metals of the Periodic Table, such as lithium, calcium, magnesium and strontium. The process consists of mixing and contacting the value metal source material, which might be an ore or concentrate, with an excess of molten metal which is acting as a reductant and lixiviant. In the process, the value metal extracted from the source material is dissolved in the excess molten metallic solvent and is subsequently extracted as a vapour by vacuum distillation. The vapour is condensed and recuperated in the metallic state.An experimental program involving eight experiments was carried out. The experimental procedure consisted in essence of melting the aluminum reductant in a crucible and adding the source material, SrCO$ sb3,$ and other reactant (Mg or Bi). (Abstract shortened by UMI.)
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Suriyachat, Duangkamol. "Zirconium solvent extraction using organophosphorus compounds." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60718.
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This study compares zirconium extraction from hydrochloric acid solutions using either Cyanex 923 or Cyanex 925 in kerosene. While both are mixtures of trialkyl phosphine oxides, the trialkyl groups in the former have straight chains, while those in the latter have branched chains.The major variables studied were hydrochloric acid, extractant and zirconium concentrations, and phase ratio. With both reagents, zirconium is extracted rapidly. Extraction increases with increasing hydrochloric acid concentration, and zirconium is loaded as its neutral tetrachloride complex by a solvation reaction. The loaded zirconium forms a di-solvate, except at high excess extractant concentrations, where solvation numbers greater than 2 are found. At a constant total chloride concentration, the zirconium extraction level is maintained if hydrochloric acid is partially replaced by lithium chloride, provided sufficient hydrochloric acid is retained to prevent zirconium hydrolysis. Distribution coefficients decease with increasing zirconium concentration, suggesting that polymerization occurs in the aqueous phase.
For given conditions, zirconium extraction into Cyanex 923 is higher than for Cyanex 925. However, loading selectivity for zirconium over other metals has not been studied. A few preliminary experiments have shown that aqueous solutions of ammonium carbonate are potential stripping agents.
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Ashrafizadeh, Seyed Nezameddin. "Solvent extraction and liquid membrane separation of rhodium." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=37698.
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The aim of this work was to develop a viable solvent-extraction based system for the separation of rhodium (Rh) from aqueous chloride solutions. Ultimately, two different systems were developed. Kelex 100, a commercially available derivative of 8-hydroxyquinoline, was used as the extractant reagent in both of these systems. One of the systems involved the supported liquid membrane (SLM) extraction of Rh. In this system a very thin microporous "Gore-Tex" polymer sheet, impregnated with an organic solution of Kelex 100, served as the SLM. The other system involved the conversion of the chlorocomplexes of Rh to bromocomplexes prior to their solvent extraction with Kelex 100.The results of the lab-scale experiments using a SLM of Kelex 100 having a surface area of 44 cm2 are reported. The optimum conditions for Rh permeation were found as a feed solution of 2.5 M HCl and a strip solution of 0.1 M HCl. The SLM was quite stable at the optimum conditions with no sign of organic loss or membrane deterioration after 72 hours of operation. It was determined that the HCl activity gradient across the membrane acts as the driving force that "pumps" the non-aquated Rh chlorocomplexes against their concentration gradient. The mechanism of Rh permeation was the ion-pair formation between the protonated Kelex 100 and RhCl6 3- complexes. The rate of Rh permeation was in the order of 10-6 mol.m-2.s-1. The mechanism of HCl and H2O permeation, which were co-extracted along with Rh chlorocomplexes, were found to be the hydration of protons at the low feed acid region and the formation of microemulsions at the high feed acid region. The permeated acid and water were separated from the SLM receiving phase by contacting the latter phase with an organic solution of trioctylamine (TOA). The chlorocomplexes of Rh(III) and acid are readily extracted to the TOA organic phase and subsequently subjected to differential stripping with a concentrated solution of Cl- and a mild NaOH solution, respectively. By interfacing the TOA solvent extraction with the SLM of Kelex 100 highly concentrated solutions of Rh (at least 10 times the initial concentration) and raffinates essentially free of rhodium were produced.
The UV-Visible investigations revealed that the bromocomplexes of Rh undergo aquation to a much lesser extent than that of the chlorocomplexes. The chlorocomplexes of Rh were converted to bromocomplexes by precipitating first the Na(NH4)2Rh(NO2)6 salt and subsequently dissolving that in an HBr solution. The newly formed bromocomplexes of Rh(III) responded very favorably to extraction with Kelex 100. Relatively high distribution coefficients, about 20, and very steep extraction isotherms were generated. The freshly loaded Kelex 100 organic was efficiently stripped upon contact with a strip solution of 6--8 M HCl and a contact time of 10--12 hours. The developed system shows high promise from a practical implementation point of view.
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Parker, N. I. "Contacting schemes for copper extraction." Thesis, University of Bradford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380357.
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Jespersson, Niklas, and Torbjörn Sandberg. "Evaluation of different non-metallic inclusions in steel chips by using electrolytic extraction : Evaluation of a methodology for electrolytic extraction and scanning electron microscopy - energy dispersive spectroscopy (SEM-EDS) analysis." Thesis, KTH, Materialvetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-298419.
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Analysing non-metallic inclusions (NMI) by conventional microscopy is prone to errors. Better imaging can be achieved by using electrolytic extraction (EE) to effectively dissolve the metal matrix, freeing the inclusions so that they can be collected on a filter. This method of studying NMI was tested on a 157C steel chip, with EE taking place three times on the same surface with increasing levels of charge applied. The relationship between charge and extracted layer depth was examined, so as to facilitate the targeting of NMI from specific depths. A selection of the extracted inclusions were micrographed with scanning electron microscopy (SEM) and had their compositions measured with energy dispersive spectroscopy (EDS). Based on this data, two methods of classifying NMI were briefly examined: manual classification, mostly based on images, and a semi-automated process based on a sorting algorithm applied to the compositions. The study implies that it is possible to dissolve a 157C steel to a desired depth by applying a charge proportional to it, but the current method introduces an error which might limit the resolution of depth by a significant amount. Also in the current method, there was no systematic way to select NMI for micrography, and no solution to this problem was found. The semi-automated classification algorithm was compromised by inaccurate readings of compositions from the EDS, and could not be thoroughly tested.Konventionell mikroskopi kan lätt ge felaktig information vid analys av icke- metalliska inneslutningar (NMI), men bättre resultat kan uppnås om metall- matrisen löses upp med elektrolytisk extraktion (EE), så att inneslutningarna frigörs och kan samlas upp på ett filter. Denna metod att studera NMI testades på ett spån av 157C-stål, med trefaldig EE på samma yta och successivt ökande maximal laddning. Sambandet mellan laddning och upplöst lagerdjup undersöktes för att möjliggöra extraktion av NMI från givna djup. Ett urval av de frigjorda inneslutningarna fotograferades i ett SEM och sammansättningarna fastslogs av EDS. Dessa data låg till grund för en undersökning av två klassifikationsmetoder för NMI: manuell klassificering, till största del bildbaserad, och en halvautomatisk klassificering där en algoritm sorterar efter sammansättningar. Denna studie antyder att ett 157C-stål kan lösas upp till önskat djup genom att åläggas en laddning proportionell mot djupet, men den nuvarande metoden introducerar ett fel som kan ha betydande påverkan på noggrannheten. Den aktuella metoden saknar ett systematiskt sätt att välja NMI för mikroskopfotografi, och ingen lösning har kunnat framföras på detta problem. Den halvautomatiska klassifikationsalgoritmen rubbades av störningar i EDS-resultaten och kunde inte undersökas till fullo.
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Smeets, Alexander Arnoldus Johannes. "Extraction of lithium by vacuum thermal reduction." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304440.
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El-Ammouri, Elias G. "Hafnium solvent extraction from chloride solutions using organophosphorus reagents (Cyanex 923, 925)." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69792.
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A comparison of hafnium solvent extraction from hydrochloric acid solutions using either Cyanex 923 or 925 (organic extractants) diluted in kerosene was established. Since understanding of the hafnium-hydrochloric acid solution is important, development of a speciation diagram for such a solution was carried out. While both Cyanex 923 and 925 are mixtures of trialkyl phosphine oxides, the trialkyl group in the former have straight chains, while those in the latter have branched chains.Experimentally, the major variables studied were hydrochloric acid, hafnium and Cyanex concentrations. Hafnium is rapidly loaded as the tetrachloride complex by a solvation reaction forming a disolvate with the extractant (923 or 925). While extraction increases with increasing acid concentration, it decreases with increasing hafnium concentration due to polymerization. Total chloride level is the controlling factor provided there is enough acid to prevent hafnium hydrolysis and polymerization. Cyanex 923 is a more powerful extractant than Cyanex 925 for given conditions. A few experiments have shown that a very dilute hydrochloric acid solution is suitable as a stripping agent.
The main objective is to evaluate the potential of Cyanex 923 (or 925) as an alternative to MIBK due to the problems associated with the latter. MIBK is the conventional extractant for hafnium and zirconium extraction and separation from hydrochloric acid/thiocyanate solutions. Thus, preliminary studies of hafnium and zirconium (existing separately or together) extraction from hydrochloric acid/thiocyanate solutions were also performed. When existing separately, hafnium and zirconium are similarly extracted into either Cyanex reagents, but when both metals coexist in the same solution, preferential separation of hafnium is observed.
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Mihaylov, Indje O. (Indje Ognianov). "Gallium solvent extraction from sulphate solutions using organophosphoric acid reagents (D2EHPA, OPAP)." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=70338.
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The subject of this work is gallium extraction from sulphate solutions--an additional source of this metal from hydrometallurgical zinc production--with organophosphorus acid reagents: di-2-ethyl hexyl phosphoric acid (D2EHPA) and OPAP, a mixed extractant consisting of mono- and di-octyl phenyl phosphoric acids. Extraction proceeds via cation-exchange and Ga$ sp{3+}$ is the reacting species. Gallium is extracted with D2EHPA mostly as GaR$ sb3$ - HR. The results for OPAP suggest existence of four reactions, which form GaM$ sb3,$ GaM$ sb2$D, GaMD$ sb2,$ and GaD$ sb3;$ this explains and allows prediction of behaviour over a wide range of OPAP compositions. Sulphate complexation causes decrease in concentration of the reacting species, and thus lower $D sb{ rm Ga}$ values and extraction rates. Prior knowledge on gallium aqueous complexes is used, and an algorithm developed, to allow quantitative prediction of complexation effects on extraction. The model of mass-transfer with chemical reaction, verified with several known criteria for reaction site determination, describes well the kinetic data for the Ga-D2EHPA system. The model is further developed to account for the stronger acidity and the monomer/dimer equilibria typical for the kind of extractants used. A detailed reaction mechanism is proposed and the first organic ligand addition is found as rate-limiting. The model parameters, estimated from extraction kinetic data, are reasonable, when compared with those obtained for other metals elsewhere. The model's predictions agree with the results from stripping kinetics; the equilibrium conditions (zero rate) can also be satisfactorily predicted, as found by comparisons with the equilibrium data. Ga-D2EHPA and Ga-OPAP systems are compared with an emphasis given to the potential for metal separation; the importance of the ligand exchange rate constant is illustrated with the example of Ga and Al extraction/stripping and their separation based on different rates with
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Benguerel, Elyse. "An investigation on the solvent extraction of rhodium from aqueous chloride solutions /." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61340.
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The aqueous behaviour of rhodium (III) (Rh) in chloride solutions was investigated with the objective of evaluating its response to solvent extraction with 8-hydroxyquinoline derivatives. A theoretical analysis of the abundance of the various chloro-complexes in solution revealed that monoaquo-pentachlororhodate and hexachlororhodate are the most common forms of Rh(III) in chloride solutions ($>$0.5M Cl$ sp{-}$) and that the relative abundance of hexachlororhodate may be lower than was previously reported.The extraction degree of Rh(III) with 8-hydroxyquinoline derivatives from solutions ranging in acidity from 0.7 to 8.0M and in chloride concentration from 0.7 to 4M was found to follow the calculated abundance of hexachlororhodate (about 5 to 40% in the region investigated). Also, the extraction mechanism was deduced to be ion-pair formation.
The extraction degree of Rh(III) from similar solutions but previously treated with SnCl$ sb2$, was also investigated, and in this case the extraction was quantitative throughout the acidity and chloride concentration ranges tested. Virtual quantitative stripping can be achieved with four five-minute contacts with 1.7M H$ sb2$SO$ sb4$ + 1M Na$ sb2$SO$ sb4$. A preliminary flowsheet for the industrial application of this solvent extraction process for Rh is presented.
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Davidson, Raymond John. "Innovations in gold extraction." Thesis, Rhodes University, 1993. http://hdl.handle.net/10962/d1004975.
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The thesis takes the form of a collection of publications and patents concerning gold extraction which were presented over a period of 18 years while employed at the Anglo American Research Laboratories.
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Mead, D. A. "Investigation of the supported liquid membrane process for metal extraction." Thesis, University of Hertfordshire, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376472.
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Bergfors, Simon, and Davida Flink. "Electrolytic Extraction of Aluminium Bifilms." Thesis, KTH, Materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-277872.
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Bifilms is the oxide layer created between two surfaces in the melt of light metals that form an oxide layer. These become planar inclusions in the final casting and are problematic for the mechanical properties such as cracks and crack initiations. Bifilms are too thin to be viewed properly in two dimension cross-section method as they will only appear as thin lines. Because of this, it is relevant to test if it is possible to use electrolytic extraction (EE) as a alternative method to investigate bifilms. Both the deeply etched surface and the inclusions on a filter from the extraction are looked at in the scanning electron microscope (SEM) to get an understanding of the size and shape of the inclusions. With this, a greater understanding of these types of defects can be achieved. After both the filtered inclusions and the surface are examined in SEM with images and Energy-dispersive X-ray spectroscopy (EDS), the images are measured in the software ImageJ. The measurements and analysis show that it is probably bifilms and that they can be relatively large, and not so circular. However, the measurements with the filter have shown high levels of oxygen and carbon. Some levels of chlorine, nitrogen and iron have also been found. But if the surface is compared to the metal surface, it can be concluded that it is likely that bifilms have been found. There are sufficient levels of aluminum and oxygen present. Images in SEM also show the appearance of film-like inclusions. If the method of electrolytic extraction is to be improved to investigate bifilms,optimizations such as filters of other compositions are recommended.Bifilms är det oxidskikt som skapas mellan två ytor i smältan hos lätta metaller som bildar ett oxidskikt. Dessa blir sedan plana inneslutningar i den slutliga gjutningen och är problematiskt för de mekaniska egenskaperna i form av sprickor och sprickinitieringar. Bifilms är för tunna för att de ska kunna ses korrekt i en tvärsnittsmetod, eftersom de bara kommer att visas som tunna linjer. På grund av detta är det relevant att testa om det är möjligt att använda elektrolytisk extraktion (EE) som en alternativ metod. Både den djupt etsade ytan och inneslutningarna på ett filter från extraktionen tittas på i svepelektronmikroskop för att få en förståelse för inneslutningarnas storlek och form. I och med det kan en högre förståelse uppnås för dessa typer av defekter. Efter att både de filtrerade inneslutningarna och ytan granskats i SEM med bilder och Energy-dispersive X-ray spectroscopy (EDS), mäts bilderna i en mjukvara, ImageJ. De mätningarna och analyserna visar att det antagligen hittats bifilms och att de kan vara förhållandevis stora, samt inte så cirkulära. Däremot har mätningarna med filtret visat höga halter av syre och kol. Även vissa halter av klor, kväve och järn har hittats. Men om ytan jämförs med metallytan så kan en slutsats dras om att det är troligt att bifilms har hittats. Där finns tillräckliga halter av aluminium och syre. Även bilder i SEM påvisar filmliknande inneslutningar till sitt utseende. Om metoden med elektrolytisk extraktion ska förbättras för att undersöka bifilms behövs optimeringar, som till exempel filterav en annan sammansättning.
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Ciriello, Carmine. "Nickel solvent extraction from dilute acidic sulphate solutions using octyl phenyl acid phosphate (OPAP)." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69789.
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The subject of this work is nickel extraction from dilute, acidic sulphate solutions through the use of organophosphorous acid reagents. The focus is primarily on OPAP, a mixed extractant consisting of mono- and di-octyl phenyl phosphoric acids, as well as on di-(2-ethyl hexyl) phosphoric acid (D2EHPA). The effects of certain parameters on the extraction of nickel, both quantitative and qualitative, have been studied. The parameters include: modifier presence, concentration and type; OPAP concentration; phase ratio; aqueous environment; age of organic solution; and mono-/di-OPAP ratio. The ability to strip nickel from the organic solution as well as selectivity and kinetic tests were carried out.The use of 10% isodecanol as a modifier was found to be essential for the purpose of OPAP solubility in kerosene and phase separation. Furthermore, the cation exchange reaction proceeds very quickly, attaining equilibrium within 10 minutes. Unlike other phosphoric acid reagents, OPAP is able to extract significant amounts of nickel in the acidic pH range of 1 to 2. As well, nickel is easily stripped using a 1.0 M sulphuric acid solution.
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Sole, Kathryn Clare. "Solvent extraction of first-row transition metals by thiosubstituted organophosphinic acids." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186480.
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Organophosphorus compounds are well known as solvent-extraction reagents. Two new reagents in this class are Cyanex 302 and Cyanex 301, the respective mono- and dithio analogs of the commercial extractant, Cyanex 272 (bis(2,4,4-trimethylpentyl)-phosphinic acid). The replacement of oxygen by sulfur in these reagents decreases their pKₐ, and enables extraction to be carried out at much lower pH than previously attained. A comparative characterization of Cyanex 272, Cyanex 302, and Cyanex 301 is undertaken. The aggregation and partitioning behavior of these reagents is determined. A comparison of the solvent extraction behavior of first-row transition-metal ions from manganese to zinc in acidic sulfate solution by these reagents is reported. Distribution coefficients shift to lower pH with increasing sulfur substitution of the extractant, the greatest effect being observed for soft Lewis acids. These reagents are found to be strong extractants for the transition metals examined, but poor extractants for alkaline-earth ions and manganese(II). Certain metal ions, in particular copper(II) and silver(I), are, however, extremely difficult to strip, which may mitigate against potential applications. Stoichiometry of the extraction reactions and the nature of the metal complexes formed are postulated based on slope-analysis techniques and spectroscopic and molecular-mass measurements. Molecular modelling of the extractants and extracted species is presented. Some reasons for the enhanced stability of the complexes formed with certain metals are discussed in terms of d-electron effects, donor-/acceptor-atom interactions, ligand-field observations, and steric effects associated with the extractants.
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Bell, Katherine Jane. "Receptors for the extraction of the hexachloroplatinate anion." Thesis, University of Nottingham, 2008. http://eprints.nottingham.ac.uk/14404/.
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This thesis presents research into the binding, extraction and transport of the hexachloroplatinate anion, [PtCl6]2-, by organic receptors in a solvent extraction process. The target anion is produced during the processing of platinum-containing ores and the aim was to develop reagents that can selectively extract [PtCl6]2- to optimise the recovery of platinum. Chapter One outlines reasons for the interest in [PtCI6]2-and provides an overview of the processes and techniques used to refine precious metals. An introduction to anion coordination chemistry relevant to the research project is also presented. Chapter Two discusses the design features incorporated into organic receptors to enable strong and selective binding of [PtCl6]2-. These features include a tertiary amine protonation site, hydrogen-bond donor groups and organic solubilising moieties. The synthesis of a series of functionalised tripodal tris(2-aminoethyl)amine based receptors with sulfonamide, amide, urea, thiourea or pyrrole NH hydrogenbond donor groups are reported. Complexation reactions between the receptors and H2PtCl6 to form [(LH)2PtCl6] ion pairs are discussed. Crystallographic analysis of the [(LH)2PtCl6]complexes with TREN-based sulfonamide, urea and amide receptors confirms the presence of hydrogen-bonds between the NH donor groups and the outer-sphere of [PtCl6]2-. The low organic solubility of the complexes prevented the study of these systems in solvent extractions. Chapter Three describes the variation of terminal substituents of the tripodal receptors with the aim of improving the organic solubility of the extractants and their [PtCl6]2-complexes. In these "second generation" receptors the terminal substituents assessed include 3, 5-dimethylphenyl, 4-iso-propylphenyl, 4-tert-butylphenyl, 3, 5- dimethoxyphenyl, 3, 4 dimethoxypheynl and 3, 4, 5-trimethoxyphenyl. Through reaction of the receptors with H2PtCl6 the solubility of the resultant complexes are assessed. Chapter Four describes the development of an optimised solvent extraction method to study the extractive behaviour receptors. A pH swing mechanism is utilised to control the uptake and release of [PtCl6]2-. The extraction results for trioctylamine and the soluble tripodal urea and amide receptors are compared. Attempts are also made to confirm the stoichiometry of the complex in solution. Chapter Five describes the synthesis of tris(2-aminoethyl)amine based receptors with hydrogen- and halogen-bond donor groups with the aim of increasing the strength of the interaction between a receptor and [PtCI6]2-. Receptors with an extended tripodal scaffold based on a tris(3-aminopropyl)amine with urea and amide moieties are also presented. The results of the complexation reactions and solvent extraction studies with these modified extractants are presented. Chapter Six presents the design and synthesis of bipodal and monopodal receptors in order to assess the role of the number of hydrogen-bond donor functionalised arms. The results of the solvent extraction studies with these receptors are discussed and comparisons made between tripodal, bipodal and monopodal extractants. The crystallographic analysis of the [(LH)2PtCl6] complexes formed between the bipodal urea and amide receptors is described. Chapter Seven highlights the important findings from this work. Conclusions are drawn as to the optimum receptor system developed and this is compared to the extractant system thought to be in current use for the extraction and transport of [PtCl6]2-.
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Aprahamian, Vicken Haroutiun. "The behaviour and control of impurities during the solvent extraction of platinum metals with an alkylated 8-hydroxyquinoline /." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61135.
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In order to understand and control the deportment of common impurity elements in the Pt(IV)-Pd(II)-HCl-8-hydroxyquinoline (TN 1911)$ sp{ rm a}$ system, their solvent extraction chemistry in chloride solution has been studied. The investigated elements were Fe(III), Cu(II), Ni(II), Zn(II), Pb(II), Sn(IV), Ag(I), As(V), Sb(V), Bi(III), Se(IV) and Te(IV). Extraction experiments carried out using multi-element and single element feed solutions helped to elucidate the extraction behaviour of the elements with the extractant TN 1911. From the collected data it was deduced that the majority formed anionic chlorocomplexes and extracted via the ion-pair mechanism involving the protonated extractant. Consequently, scrubbing procedures were developed to control the deportment of these elements. These scrubbing steps were then incorporated into a tentative flowsheet which was simulated in a batch-wise fashion in the laboratory. The most contaminating elements were found to be Zn(II), Pb(II), Ag(I), Te(IV), Se(IV) and Bi(III). The first five were effectively scrubbed with 2.0M HCl whereas Bi(III) could only be scrubbed with 2.0M H$ sb2$SO$ sb4$ at A/O ratios of $>$3:1. The element Sn(IV) which was found to build-up in the organic, could only be scrubbed with a 1.0M NaOH solution for long contract times (60 minutes). ftn$ sp{ rm a}$A proprietary alkylated derivative of 8-hydroxyquinoline (Schering Berlin AG).
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Benguerel, Elyse. "Solvent extraction of rhodium from chloride solutions in the presence of SnCl2 with Kelex 100tm." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40321.
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The aim of this work was to devise and investigate a solvent extraction system for rhodium, from aqueous chloride solutions, having potential industrial applicability. The extractant investigated was Kelex 100, a commercially available derivative of 8-hydroxyquinoline. Ultimately, two different systems were developed. Both are based on an initial complexation reaction between the aqueous rhodium chloride complexes, (RhCl$ rm sb{6-n}(H sb2O) sb{n} rbrack sp{(3-n)-}$ and stannous chloride, referred to as the activation stage, but the two systems use a different Sn:Rh molar ratio. In both cases, the Rh-Sn complexes, either (Rh(SnCl$ sb3) sb5 rbrack sp{4-}$ or (RhCl$ rm sb3(SnCl sb3) sb3 rbrack sp{3-},$ respond well to extraction with Kelex 100. One of the main differences between the two systems is in the stripping medium which is used to transfer the rhodium from the loaded organic phase back into an aqueous phase. In the case of the high Sn:Rh ratio feeds, the stripping stage is based on sulfuric acid, whereas in the case of low Sn:Rh ratio feeds, the rhodium is stripped from the organic phase using a sulfite containing hydrochloric acid solution.The two systems were characterized in terms of their equilibrium and kinetic behaviour during all three stages; activation, extraction, and stripping. Activation was found to proceed either at room temperature or at elevated temperatures and the above-mentioned expected Rh-Sn complexes were identified through $ sp{119}$Sn NMR and Raman spectroscopy. The extraction stage was found to be quantitative for rhodium and it was also found to be very rapid, with contact times of less than five minutes sufficient for rhodium extraction. The extraction mechanism was determined to be ion-pair formation with the protonated Kelex 100 molecules at a stoichiometry such that the overall charge in the organic phase is neutral, i.e., three Kelex 100 molecules for (RhCl$ rm sb3(SnCl sb3) sb3 rbrack sp{3-}$ and four for (Rh(SnCl$ sb3) sb5 rbrack sp{4-}.$
The stripping stages were the most problematic for both systems. In one case, the system was eventually abandoned due to limitations in the amount of rhodium which could be transferred to the sulfuric acid strip solution. For the low Sn:Rh system, reasonable rhodium transfer and concentration level were obtained. The rhodium complex in the strip solution has been proposed to be (RhCl$ rm sb2(SO sb3) rbrack sp{3-}.$ Strip solutions up to $4 times10 sp{-2}$M in rhodium concentration have been produced, from initial feed solutions having a rhodium concentration of about $4 times10 sp{-3}$M. Preliminary flowsheets are proposed for further refinement for both systems, although only the second system, the low Sn:Rh ratio system which uses sulfite stripping, is advocated for further development.
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Buyukakinci, Ergin. "Extraction Of Nickel From Lateritic Ores." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609291/index.pdf.
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The aim of this study was to extract nickel and cobalt from the lateritic nickel ores of Gördes region by hydrometallurgical methods under the optimum conditions. Limonitic and nontronitic types of Gö
rdes lateritic nickel ores were used during experiments. Agitative and column leaching experiments at atmospheric pressure were conducted with various parameters
these were duration, temperature and initial sulfuric acid concentration of leach solution. It was shown that in agitative leaching, under the optimum conditions that were determined as 24 hours of leaching at 95°
C with initial sulfuric acid concentration of 192.1 g/L for nontronite and 240.1 g/L for limonite, nickel and cobalt extractions were 96.0% and 63.4% for nontronite
93.1% and 75.0% for limonite, respectively. Overall acid consumptions of ores were calculated as 669 kg H2SO4/ton dry ore for nontronitic type nickel ore and 714 kg H2SO4/ton dry ore for limonitic type nickel ore. Column leaching experiments also showed that nickel and cobalt could be extracted from both ore types by heap leaching. Nontronite type of laterite was found to be more suitable for column leaching by sulfuric acid. In column leaching, the calculated nickel and cobalt extractions were 83.9% and 55.2% for nontronite after 122 days of leaching with 100 g/L sulfuric acid concentration. Acid consumption of nontronite was found to be 462 kg H2SO4/ton dry ore.
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Du, Toit Zita. "Simulation of a palladium extraction circuit." Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019/536.
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Rolinska, Monika. "Extraction Replicas of Common Engineering Alloys for Analysis of Small Precipitates." Thesis, KTH, Materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-291204.
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Characterization of small precipitates is important for development of new alloys. One inherent difficulty in characterisation of small precipitates with electron microscopy techniques while the particles are embedded in the matrix, is that the surrounding bulk material will contribute to the analysed signal- limiting, for example, the quantification of the composition of particles. In order to avoid the matrix contribution, the extraction replica technique was developed in the 1950's. Extraction replicas are made by extracting only the particles from a material onto a thin film for further analysis by scanning or transmission electron microscopy. Different types of particles can be examined by this technique, including various carbides, nitrides, oxides and borides, as well as many intermetallic phases. In this work, direct replication techniques were compared to two-stage replication for low-alloyed steel, concluding that both are suitable for qualitative analysis, but direct replication is preferred for quantitative analysis. Successful replication of the zirconium-based Zirlo and the stainless steel 254 SMO was performed, where the precipitated phases were isolated and the composition quantified. Particle extraction was successful also for the zirconium-based Zircaloy-2 and two types of aluminium alloys, but no quantification of composition could be made due to different problems associated with etching of each alloy, showing that properchoice of etchant is crucial for the quality of the replicas.Karaktärisering av små utskiljningar är viktigt för utveckling av nya legeringar. En svårighet vid karaktärisering av små utskiljningar med elektronmikroskopi när partiklarna sitter kvar i matrisen är att matrisen kommer ge ett bidrag till den analyserade signalen, därför är t.ex. möjligheterna för kvantifiering av sammansättning begränsade. För att undvika bidraget från matrisen utvecklades extraktionsrepliker på 1950-talet. Extraktionsrepliker tillverkas genom att extrahera partiklar från ett material till en tunn film som sedan kan analyseras med hjälp av svep- eller transmissionselektronmikroskopi. Olika sorters partiklar kan undersökas med hjälp av denna metod. Dessa inkluderar olika typer av karbider, nitrider, borider, oxider och många olika sorters intermetalliska partiklar. I detta arbete jämfördes direkta metoder med tvåstegsrepliker på låglegerat stål. Slutsatsen blev att båda metoderna lämpar sig för kvalitativ analys av små partiklar, men direkta metoder är att föredra för kvantitativ analys. Lyckade repliker tillverkades även av zirkoniumlegeringen Zirlo och det rostfria stålet 254 SMO, där utskiljningarna kunde isoleras och sammansättningen kvantifieras. Extraktion av partiklar var lyckad även för zirkoniumlegeringen Zircaloy-2 samt två typer av aluminiumlegeringar, men ingen kvantifiering av sammansättningen kunde göras på grund av olika problem relaterade till den valda etsmetoden för varje legering, vilket visar att valet av etsmedel ar avgörande för kvaliteten av replikerna.
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MacLean, Donald William John. "The kinetics of zinc extraction in the di(2-ethylhexyl) phosphoric acid, n-heptane-zinc perchlorate, perchloric acid, water system." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/30023.
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The kinetics of zinc extraction from perchlorate solutions with di(2-ethylhexyl) phosphoric acid in n-heptane have been measured using the rotating diffusion cell technique.
The extraction of zinc is controlled by the mass transfer of reactants (Zn²⁺ and D2EHPA) to the interface. At low zinc concentrations, the system is controlled by the aqueous transport of Zn²⁺ to the interface; at higher zinc concentrations transport of D2EHPA becomes rate controlling. For the range of D2EHPA concentrations examined, the transport of D2EHPA is rate controlling. Bulk pH has a negligible effect, except perhaps at the lowest pH values examined, where there may be a slight decrease in extraction rate. This decrease was attributed to less favourable thermodynamics at low interfacial pH values. It appears that the chemical reaction rate is fast enough that it has a negligible effect on the overall extraction rate. A basic mathematical model was developed which is adequate for predicting the extraction rate under variable conditions of zinc concentration, D2EHPA concentration, and pH.
The effect of using a partially loaded organic extractant was also investigated, and the system was found to be mass transfer controlled. An extended mathematical model was developed which predicts that the speciation of organic complexed zinc changes with increasing preload, and at high loadings the direction of ZnL₂HL and ZnL₂(HL)₂ flux reverses, with these species providing extractant to the interface. At very high loadings, ZnL₂HL provides almost all the extractant to the interface.
Experimental studies of the effect of temperature on the rate of zinc extraction resulted in a calculation of the activation energy which was consistent with a diffusion controlled mechanism. Finally, the effect of different filter pore sizes on extraction was examined. The extraction rate decreases significantly with a very small filter pore size, while there appeared to be little or no effect for larger filter pore sizes. For the filter pore size used in this study, it was therefore concluded that the filter pores do not pose an additional resistance to mass transfer.Applied Science, Faculty of
Materials Engineering, Department of
Graduate
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Guo, Shuo. "Evaluation of deformed MnS in different industrial steels by using electrolytic extraction." Thesis, KTH, Materialvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-217880.
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The inclusions have a different chemical composition and give the steel different mechanical properties. These inclusions affect several properties of steel. In order to understand how the inclusions will affect the steel properties, the electrolytic extraction of 3D investigate method is applied on the steel grade of 42CrMo4. Then follow with Scanning Electron Microscope (SEM) observation. Steel samples from both ingot and rolling with and without heat treatment are observed and compared with different ratios. The result shown that, heat treatment can be applied for removing carbides successfully. And most inclusions are belonging to Type RS which is rod like MnS. The percentage of broken particles can be up to 80%, which means that the reason for the inclusions broken should be find. And heat treatment can affect the characteristics of elongated MnS.
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MacRuary, Kirstian Jennifer. "Investigation into the mode of action of chloride and chloridoplatinate extraction : a computational and experimental study." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/25794.
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This thesis investigates the mode of action of cationic reagents in the recovery of platinum group metals (PGMs) by anion exchange solvent extraction. Industry uses a range of extractants to achieve efficient concentration and separation of PGMs in hydrometallurgical processes, but an understanding of the processes at a molecular level is limited and restricts the options to improve efficiency. The research, sponsored in part by Johnson Matthey and Anglo American, explores two different aspects of the mode of action of reagents used to recover chloride and platinum. Chapter 1 reviews the extraction of chloridometalates in hydrometallurgy and other methods used to recover PGMs. The chapter also covers current ideas on whether formation of outer-sphere anion-cation molecular assemblies or whether larger supramolecular aggregates are responsible for the extraction of PGMs. These two separate routes of study can be investigated by various computational and experimental methods, which are discussed in Chapter 2. In Chapter 3, the model systems chosen to develop the methodologies utilised throughout the thesis are presented. The development involves the extraction of chloride ions by tributyl-phosphate (TBP) and then is extended to extraction of PGM chloridometalates in Chapter 4. Computational methods are used to probe the atomistic and supramolecular theories in predicting the most likely assemblies which will be formed in the transfer of anions between the aqueous and organic phase. Slope analysis and the determination of the contents of the organic phase is used to validate computational models, along with spectroscopic techniques to determine shape and size of assemblies formed during extraction. The application of these methodologies to an amide extractant is discussed in Chapter 5. Computational methods predict the probability of formation of specific complex assemblies during the extraction of PtCl62- by protonated forms of the amide. Determination of the stoichiometry involved in formation of the complex assemblies by slope analysis is reported along with analysis of water, metal and chloride content to confirm the computational model. Final conclusions on all systems explored within the thesis and suggestions for future work are presented in the final chapter. The combination of experimental and computational methods are shown to be very efficient in defining mechanisms of extraction, involving determination of structures formed during the process and how and why they form.
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Ozdemir, Veysel. "Hydrometallurgical Extraction Of Nickel And Cobalt From Caldag Lateritic Ore." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607777/index.pdf.
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In this study, an attempt has been made to hydrometallurgical extraction of cobalt and nickel by atmospheric pressure sulphuric acid leaching and a pug-roast-leach process using two stage roasting for lateritic ore. The ore used in the study was obtained from Çaldag Lateritic Ore, Manisa, Turkey. The metal contents of the ore are 2.1 % Ni, 0.12 % Co, 32.45 % Fe, 1.01 % Mn, 2.58 % Cr, 0.78 % Mg and 1.01 % Al. The reserve of lateritic ore deposit is approximately 40 million tonnes. In the study, first sulphuric acid leaching was applied at atmospheric pressure for leaching the Ç
aldag lateritic ore. The effect of various parameters, such as leaching time, leaching temperature, particle size, pulp density and acid strength on Ni and Co extractions were determined. By leaching at 80oC for 40 wt % H2SO4 addition of ore, 1/3 pulp density, Ni and Co extractions were found 44.49 % and 53.03 % respectively, yielded a pregnant solution containing 3.11 g/L Ni and 0.12 g/L Co. But the result of atmospheric pressure sulphuric acid leaching was considered insufficient from the recovery point of view. In the pug-roast-leach process, which is consisted of a two stage roasting followed by water leaching, decomposition temperature differences of sulphates of cobalt, nickel and iron are exploited. In this process, amount of acid, sulphatization and decomposition temperature, sulphatization and decomposition time, leaching temperature and time, solid/liquid ratio, and the effect of water addition during pugging were optimized. Under the optimized conditions (sulphuric acid: 25 wt % of ore
moisture: 20 wt % of ore
sulphatization temperature: 450oC
sulphatization time: 30 minutes
decomposition temperature: 700oC
decomposition time: 60 minutes
leaching temperature: 70oC
leaching time: 30 minutes and solid-liquid ratio: 1/4 by weight), Co and Ni extractions were found 91.4 and 84.4 percent, respectively. A pregnant solution containing 3.084 g/L Ni and 0.185 g/L Co was obtained. These results were considered sufficient for the leaching of lateritic nickel ores.
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O'Brien, Evan Daniel. "Welding with Low Alloy Steel Filler Metal of X65 Pipes Internally Clad with Alloy 625: Application in Pre-Salt Oil Extraction." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1469018389.
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Mehta, Punita. "Evaluating the potential of alder-Frankia symbionts for the remediation and revegetation of oil sands tailings." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84099.
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Tailings are the waste produced as a result of the extraction of oil from the tar sands in northern Alberta. Many avenues for the reclamation of tailings are being researched, but one area that has received little attention is phytoremediation. The Alder-Frankia symbiotic relationship in the tailings was investigated for its potential in revegetation and remediation of the tailings. Two species of alders were examined Alnus glutinosa and A. rugosa. The impact of the alders was monitored through the investigation of the differences in the microbial community present in the oil sands tailings and composite tailings (CT) with and without alders. For our investigation we used culture dependent techniques (plate counts and mineralization assays) and culture independent techniques (16S rRNA gene PCR, catabolic PCR and DGGE). The alders lowered the pH of the tailings, increased rates of mineralization, increased the general microbial population in the tailings by one to two orders of magnitude and increased the microbial diversity.A. rugosa however, had a greater impact on the mineralization of poly aromatic hydrocarbons (PAHs) and, being native to Alberta, was chosen for further experimentation, using only composite tailings. The aim of the experiments was to determine the effect of a Frankia inoculum on the growth of A. rugosa in (CT) and the associated microbial community. The microflora in the bulk soil, rhizosphere and inside the root of inoculated and non-inoculated A. rugosa were compared through microbial enumerations of the community, with general and selective media and mineralization assays. A. rugosa inoculated with Frankia was taller and the roots were more developed and the endophytic community of inoculated A. rugosa had greater rates of naphthalene mineralization.
The results indicate that A. rugosa inoculated with Frankia could be used for the phytoremediation of tailings and for the re-establishment of a forest ecosystem.
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Lakay, Eugene Marlin. "Novel ion-exchange materials derived from poly(styrene-co-maleimide) and a study of the extraction and recovery of gold (III) chloride from acidic solutions." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80148.
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Thesis (PhD)--Stellenbosch University, 2013.ENGLISH ABSTRACT: In this study an economical, environmentally friendly, selective and efficient process for the extraction and recovery of [AuCl4]- from aqueous acidic chloride-rich solutions, particularly those aqueous solutions having low concentrations of the precious metal complexes has been investigated. Functionalized poly(styrene-co-maleimide) (PSMI) nanoparticles were synthesized by thermal imidization of the poly(styrene-co-maleic anhydride) (PSMA) copolymer with 3-N,N-dimethylaminopropylamine. Stable water-based dispersions were obtained containing spherical, monodisperse PSMI nanoparticles with a narrow size-distribution and average diameters of 50 ± 5 nm. The specific surface area of the bulk PSMI nanoparticles is 88.1 ± 2.2 m2/g with an average pore diameter of 82.3 Å. 13C NMR, FTIR and elemental analyses confirmed the successful and complete conversion of PSMA into the PSMI derivative. The functionalized PSMI nanoparticles synthesized were investigated as a novel anion-exchange material for the extraction of [AuCl4]- ions from aqueous acidic solutions. Batch sorption studies were carried out as a function of various parameters, such as initial gold concentration, PSMI mass, contact time and agitation rate. The [AuCl4]- extraction occurred with extremely fast sorption kinetics and is dependent on the rate of agitation during the batch sorption process. The functionalized PSMI nanoparticles show a maximum gold loading capacity of 1.76 mmol/g (347.7 mg/g). Langmuir and Freundlich isotherm models were applied to analyze the experimental sorption data. The best model describing the sorption process is given by the Langmuir model. Desorption efficiencies of about 80 % and 93 % were obtained using acidified thiourea (0.25 M thiourea/2 M HCl) and a mixture of 10 M HNO3/0.5 HCl as elutant solutions, respectively. X-ray photoelectron spectroscopy (XPS) analysis unambiguously confirms that the immobilized gold species exists in several oxidation states of 0, +I and +III on the PSMI nanoparticles. This proves that the [AuCl4]- ions initially present in the gold feed solutions unfortunately are subject to a reduction phenomenon on the surface of the functionalized PSMI nanoparticles. The existence of the various gold species contributed significantly to poor desorption efficiencies. In addition to PSMI nanoparticles, micro- to millimeter size PSMI resin beads was prepared by an electrospray methodology. This allows for a wide range of PSMI spherical and quasi-spherical bead diameters of shape to be prepared by manipulation of the experimental conditions employed during the electrospray process, such as the concentration of the PSMI in solution, the capillary tip-to-collector distance, flow rate and the applied voltage. 13C NMR and FTIR spectroscopy analyses show that the electrospray methodology allows PSMI resin beads preparation without any change in chemical composition of the PSMI material. Surface area and porosity analysis shows that 450 μm and 1620 μm PSMI beads selected for use in the gold extraction experiments are microporous and have BET specific surface areas of 2.8 ± 0.4 m2/g and 2.0 ± 0.1 m2/g, respectively. Micro- to millimeter size PSMI resin beads of 450 μm and 1620 μm diameter were tested as potential anion-exchange resins for the extraction of [AuCl4]- from aqueous acidic solutions. The time-dependent studies reveal that the extent of gold uptake increases with an increase in contact time and is dependent on the gold concentration in the [AuCl4]- feed solutions. A maximum loading capacity of 120.7 mg/g and 98.16 mg/g was attained for the 450 μm and 1620 μm resin beads, respectively. The experimental sorption data followed a linear trend consistent with a Freundlich sorption model. This sorption trend for [AuCl4]- suggests that a multi-layer sorption process predominates. Desorption of immobilized gold species from the loaded PSMI resin beads was investigated using various elutants such as HCl, HNO3, thiourea, NaCN and NaOH solutions. The best results were obtained using a mixture of 10 M HNO3/0.5 M HCl as elutant with a desorption efficiency of about 97%. Finally, superparamagnetic magnetite (Fe3O4) nanoparticles with a high degree of crystallinity and phase purity were synthesized by a chemical co-precipitation of Fe2+ and Fe3+ salts. The average diameters of the obtained Fe3O4 nanoparticles were about 7 – 8 nm. The Fe3O4 nanoparticles were coated with oleic acid surfactant molecules and used as seed particles for the preparation of 50 nm diameter magnetic PSMI nanoparticles via an in situ imidization reaction. TEM analysis confirmed that the magnetically responsive PSMI nanoparticles consist of magnetite core-polymer shell structure, although more work is required to perfect such materials.
AFRIKAANSE OPSOMMING: In hierdie studie is ‘n ekonomiese, omgewings vriendelike, seleketiewe en effektiewe proses vir die ekstraksie en herwinning van [AuCl4]- uit suur chloried-ryke oplossings, spesifiek oplossings van lae konsentrasies van edel metal komplekse was bestudeer. Gefunksionaliseerde poli(stireen-ko-maleïmied) (PSMI) nanopartikels was gesintetiseer deur middel van termiese imidisasie van die poli(stireen-ko-maleïk anhidried) kopolimeer met 3-N,N-dimetielaminopropielamien. Stabiele dispersies in water was gevind wat soos sweriese mono-disperse PSMI nanopartikels met ‘n noue partikel-grootte verspreiding met ‘n gemiddelde deursnee van 50 ± 5 nm. Die spesifieke oppervlak area van die massa PSMI nanopartikels is 88.1 ± 2.2 m2/g met ‘n gemiddelde porie-grootte van 82.3 Å. 13C NMR, FTIR en elementêre analiese bevestig die suksesvolle en volledige omskakeling van PSMA na PSMI. Die gefunksionaliseerde PSMI nanopartikels was bestudeer as ‘n nuwe anion-uitruil material vir die ekstraksie van [AuCl4]- ione uit suur oplossings. Stel sorpsie studies was uitgevoer as ‘n funksie van verskeie parameters soos onder andere die goud konentrasie in oplossing, PSMI massa, kontak tyd en ‘n mengings tempo. Die [AuCl4]- ekstraksie gebeur met ‘n geweldige sorpsie kinetika en is afhanklik van die mengings tempo gedurende die stel sorpsie proses. Die gefunksionaliseerde PSMI nanopartikels het ‘n maksimum goud sorpsie kapsiteit van 1.76 mmol/g (347.7 mg/g). Langmuir en Freundlich isoterm modelle was gepas en geanaliseer op die experimentele sorpsie data waarvan die Langmuir isoterm model die data die beste gepas het. De-sorpsie effektiwiteit van ongeveer 80 % en 93% was vekry vir die aangesuurde thiourea (0.25 M thiourea/2 M HCl) en ‘n mengsel van 10 M HNO3/0.5 M HCl as elueer oplossings, onderskeidelik. X-straal foto-elektron spektroskopie (XPS) analiese bevestig ongetwydeld die geimmobileerde goud spesies in oksidasietoestande van 0, +I, en +III op die PSMI nanopartikels. Hierdie is bewyse dat die [AuCl4]- oorspronklik teenwoordig in die goud oplossings is onderhewe auto-reduksie fenomeen op die oppervlak van die gefunksionalieerde PSMI nanopartikels. Die bestaan van verskeie goud spesies dra by tot die power de-sorpsie effektiwiteit van ge-immobiliseerde goud. Bykomend tot die nanopartikels is mikro- tot millimeter grootte PSMI partikels voorberei met ‘n elektro-sproei proses. Hierdie metode stel ons instaat om ‘n wye reeks sferiese en quasi-sferiese PSMI partikel se deersnee voorteberei. Deur die manupulasie van die eksperimentele kondisies gedurende die elektro-sproei proses, soos die konsentrasie van die PSMI in oplossing, die kapilêre punt-tot-ontvanger afstant, vloeispoed en die toegepasde potensiaal. 13C KMR en FTIR spectroskopiese analiese wys dat die elektro-sproei proses die PSMI partikel bereiding toelaat sonder enige veranderinge in die chemiese samestelling van die PSMI materiaal. Oppervlak area en porie-grootte analise wys dat 450lksdfhld en dskl jmm partikels gebruik in die goud ekstraksie eksperimente is mikro-porieës en het spesifieke oppervlak-areas van 2.8 ± 0.4 m2/g en 2.0 ± 0.1 m2/g onderskeidelik. Mikro- tot millimeter grootte poli(stireen-ko-maleimied) (PSMI) partikels van 450 μm en 1620 μm deursnee was getoets as potensieele anion-uitruilings-hars vir die ekstraksie van [AuCl4]- vanuit suur oplossings. Die tyd afhanklike studies gee aanduiding dat die mate van goud opname toeneem met ‘n toename in kontak-tyd en is afhanklik van die goud konsentrasie in die [AuCl4]- oplossings. ‘n Maksimum opname-kapasiteit van 120.7 mg/g en 98.2 mg/g was verkry vir die 450 μm en 1620 μm hars partikels onderskeidelik. Die eksperimentele sorpsie-data volg ‘n lineêre neiging in ooreenstemming met die Freundlich model. Die sorpsie neiging van [AuCl4]- dui aan dat ‘n meervuldige laag sorpsie proses domineer. De-sorpsie van die geimobiliseerde goud spesies vanaf die PSMI hars partikels was bestudeer deur gebruik te maak van verskeie elueermiddels soos HCl, HNO3, thiourea, NaCN en NaOH oplossings. Die beste resultate is verkry deur ‘n mengsel te gebruik van 10M HNO3/0.5M HCl as elueermiddel met n de-sorpsie effektiviteit van ongeveer 97%. Superparamagnetiese magnetiet (Fe3O4) nanopartikels met ‘n hoë graad van kristaliniteit en fase-reinheid was voorberei deur ‘n chemiese ko-neerslagvorming van Fe2+ en Fe3+ soute. Die gemiddelde deursnee van die Fe3O4 nanopartikels was ongeveer 7 – 8 nm. Die Fe3O4 nanopartikels was omhul met oleic suur benatter molekules wat gebruik word as saadjies vir voorbereiding van 50 nm deursnee-magnetiese PSMI nanopartikels deur middel van ‘n imidisasie reaksie. TEM analiese bevestig dat die magnetiese PSMI partikels nanopartikels bestaan uit ‘n magnetiet-kern polimeer-skil struktuur.
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Symington, Sager M. Sheena. "The environmental and social history of the O'Donnell roast yard and townsite near Sudbury, Ontario." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ40488.pdf.
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Govan, Premesh. "Manipulating aqueous chemistry environments in extractive metallurgy." Master's thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/10529.
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The Anglo Research Nickel (ArNi) process is a novel extractive metallurgical process that arose out of the need to develop a processing route for the recovery of nickel from lateritic ore deposits that is both economical and environmentally acceptable.
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Makaka, Siphokazi. "The development of an empirical mass transfer relationship for the extraction of copper ions in a carrier facilitated tubular supported liquid membrane system." Thesis, Cape Peninsula University of Technology, 2011. http://hdl.handle.net/20.500.11838/866.
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Thesis submitted in fulfilment of the requirements for the degree
Master of Technology: Chemical Engineering
in the Faculty of Engineering
at the Cape Peninsula University of Technology
2011Treatment of waste material from mining and mineral processing is gaining increasing importance as a result of the increasing demand for high purity products and environmental concerns. Supported liquid membranes (SLMs) have been proposed as a new technology for the selective removal of metal ions from a solution. This technology can be described as the simultaneous extraction and stripping operation, combined in a continuous single process unit. Theoretically, the rate of mass transfer through SLM systems could be controlled by three resistances, namely: · Resistance through the feed-side · Resistance through the strip-side laminar layers; and · Diffusion through the membrane. It has been reported that transport resistance in the feed-side laminar layer is controlling. (Srisurichan et al, 2005:186). The objective of this research was to extract copper ions in a TSLM system, evaluate the effect of the feed characteristics on the feed-side laminar layer and determine a relationship between the applicable dimensionless numbers, i.e. Sherwood, Schmidt and Reynolds numbers. A Counter-current, double pipe Perspex bench-scale reactor, consisting of a single hydrophobic PVDF tubular membrane mounted vertically within, was used for the test work. The membrane was impregnated with LIX 984N-C and became the support for this organic transport medium. Dilute Copper solution passed through the centre pipe and sulphuric acid, as a strippant, passed through the shell side. In this test work, Copper was successfully transported from the feed-side to the strip-side and through repetitive results; a relationship between dimensionless numbers was achieved.
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Photos, Euphemia. "Early extractive iron metallurgy in N Greece : a unified approach to regional archaeometallurgy." Thesis, University College London (University of London), 1987. http://discovery.ucl.ac.uk/1348990/.
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Aspects of early Greek extractive iron metallurgy are investigated here, for the first time, with particular emphasis on Macedonia, Greece's most metals-rich province. The subject is approached experimentally by considering equally the ores, slag and artefacts of iron in Macedonia, through the analytical examination of archaeological slag and artefacts, the experimental smelting of Macedonian ores and subsequent analytical investigation of the slag and blooms produced. The mineral resources geology of Macedonia is presented. The historical background to mining and metal working in Macedonia from the Early Iron Age (tenth century BC) to the turn of the present century is documented. The literature on the introduction of iron into Greece, and the East Mediterranean more generally, is critically reviewed, and in the light of results obtained, especially from Thasos, it is argued that the origins of iron making in Macedonia, if not elsewhere in Greece, should be sought locally during the Late Bronze Age. Despite the absence of excavated furnace remains, it has been possible, through analytical examination of metallurgical waste, to trace the operation of the bloomery in Macedonia continuously for nearly thirty centuries. That a considerable variety of iron ores were exploited was elucidated by the analysis of slag inclusions in a large number of iron artefacts from Vergina and from sites on Thasos and the East Macedonian Mainland, spanning chronologically the Early Iron Age to the Byzantine period. The titanium-rich magnetite sands on Thasos and at Vrontou on the Mainland were shown to have been worked from the Hellenistic/Roman to the turn of this century. A second century BC nickel-rich bloom found at the Hellenistic site at Petres in West Macedonia testified, for the first time, to the smelting of nickel-rich iron laterites in Greece, while the manganese-rich iron deposits in Palaia Kavala district were worked for their precious metals content, probably during Ottoman times and perhaps as early as the Classical period. It is suggested that the Skapte Hyle of the classical texts may be located in the Palaia Kavala district. A fresh appraisal of the depiction of furnaces on Black and Red Figure Attic vases of the sixth and fifth centuries BC suggests that the bloomery process may have developed at that time to a level not previously suspected. The classical texts, the function of the cauldron on the furnace top and experimental meltings carried out in the process of this work all point to the production of wrought iron/steel through the decarburisation of high carbon iron in a fining hearth. It is argued that the furnaces depicted on the vases are themselves fining hearths, the cauldron sealing the furnace top in order for the air blast to be directed over the molten mass.
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Burns, Alexander D. "Uranous sulfate precipitation as a novel route to uranium purification in extractive metallurgy." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/54279.
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Uranous sulfate can be crystallized from uranium(IV)-containing solutions by raising the temperature and adding sulfuric acid. Several important aspects of the process have never been investigated, however, making its successful application as a real-world extractive metallurgy technology far from certain. This dissertation addresses several fundamental questions surrounding the crystallization of uranous sulfate from acidic process solutions. The effects of various parameters on the solubility of uranous sulfate and the kinetics of its precipitation are demonstrated, including temperature, acid concentration, and agitation, based on the results from a series of bench-scale experiments. The effects of various impurities on the selectivity and efficiency of the crystallization process are also determined. Two new uranous sulfate x-hydrate polymorphs, the hexahydrate and the octahydrate, are characterized using single-crystal x-ray diffraction, vibrational spectroscopy, and chemical assay data, and an understanding of the conditions under which they form is developed. The thermal stability and decomposition characteristics of uranous sulfate tetrahydrate, hexahydrate, and octahydrate are demonstrated through fundamental thermodynamic calculations and through the examination of thermal analysis data. The fundamental kinetics of uranium(IV) oxidation in acidic solutions are quantified through the interpretation of experimental data under various conditions of acidity, temperature, and oxygen partial pressure. Finally, a hydrometallurgy flow sheet incorporating uranous sulfate precipitation is presented, and the viability of the complete process is demonstrated experimentally, including electrolytic reduction, precipitation, filtration, drying, and calcining. This work demonstrates that uranous sulfate precipitation is viable as a hydrometallurgical process technology, and that further work is justified.Applied Science, Faculty of
Materials Engineering, Department of
Graduate
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Kellner, Hans. "Study of Non-metallic Inclusion in Alloy 825." Doctoral thesis, KTH, Tillämpad processmetallurgi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-218036.
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It is well known that inclusions affect the properties of steels and alloys. Therefore, it is important to understand what type of inclusions that exist and how they behave and especially with a focus on large size inclusions. Thus, the large size non-metallic inclusions in ferroalloy FeTi70R were investigated in two dimensions (2D) by using scanning electron microscopy (SEM) in combination with an energy dispersive technique (EDS). It was found that the FeTi70R ferroalloy contain complex oxide inclusions consisting mostly of CaO, SiO2 and TiOx. Furthermore, experimental trials were performed to investigate how these inclusions behaved when entering a melt. More specifically, a comparison between pure Fe and an Alloy 825 grade were made. These results determined the parameters effect on the transformation of the inclusions in the melt. The large size non-metallic inclusions in Alloy 825 during the ladle treatment were investigated during industrial trials by using both two dimensional (2D) and three dimensional (3D) microscopic investigations. The results showed that inclusions consisted of spherical oxides and clusters made up of oxides and nitrides. Further investigations found that the spherical inclusions were transformed from existing NMI in the FeTi70R ferroalloy and slag particles. As for the clusters, they originate from deoxidation products. Furthermore, small inclusions precipitated in the local zones around the added FeTi70R ferroalloy and titanium nitrides. Investigations also found that only Al2O3-MgO and TiN clusters exist after casting. Industrial trials were performed during the last period of the ladle treatment and using a combined electromagnetic (EMS) and gas (GS) stirring. The purpose to investigate the effect of different EMS directions on the agglomeration and on the removal of Al2O3-MgO and TiN clusters. The investigations were then performed in 3D after an electrolytic extraction of the metal samples. The results show that electromagnetic stirring in the upwards direction is best for the agglomeration of the Al2O3-MgO and TiN clusters. However, electromagnetic stirring in the downwards direction is more effective to remove clusters from the melt. This is in agreement with the theoretical predictions based on Stokes’, Brownian and Turbulent collisions. Also, the calculations showed that for Al2O3-MgO clusters with sizes <20 μm the Turbulent collision is the defining factor for agglomeration. However, both Stokes’ and Turbulent collisions are dominant for larger inclusions. For the TiN clusters, turbulent collisions is the dominant factor. Further investigations with more heats and stirring modes were done by using 2D microscopic investigations. More specifically, the number, size, composition and morphology of different inclusions were determined by using SEM in combination with EDS and Inca Feature analyses. The results show that the EMS in downwards direction with a 0.04 m3 min-1 gas flow rate promotes a general removal of Al2O3-MgO and TiN inclusions. Furthermore, that the upwards EMS direction promotes a drastically increase of inclusions having an equivalent size smaller than 11.2 μm. Moreover, the stirring with a 0.02 m3 min-1 gas flow rate has a better removal rate for both downwards and upwards stirring directions compared to the stirring with a 0.04 m3 min-1 gas flow rate. However, no influence on the inclusion composition and morphology could be seen from the different stirring modes.Det är välkänt att inneslutningar påverkar egenskaperna i stål och legeringar. Därför är det viktigt att förstå vilken sorts inneslutningar som existerar samt hur de beter sig, särskilt stora inneslutningar. Således undersöktes de stora icke-metalliska inneslutningarna i ferrolegeringen FeTi70R i två dimensioner (2D) genom att använda svepelektronmikroskopi (SEM) i kombination med energidispersionsteknik (EDS). Det visade sig att ferrolegeringen FeTi70R innehåller komplexa oxidinneslutningar bestående huvudsakligen av CaO, Si02 och TiOx. Vidare utfördes laborativa försök för att undersöka hur dessa inneslutningar uppträder när de kommer ner i det smälta stålet. Mer specifikt så gjordes en jämförelse mellan rent Fe och Alloy 825 legeringen. Dessa resultat fastställde hur olika parametrar påverkade inneslutningarnas omvandling i smältan. De stora icke-metalliska inneslutningarna i Alloy 825 legeringen under skänkugnsbehandlingen undersöktes vid industriella försök med hjälp av både tvådimensionella (2D) och tredimensionella (3D) mikroskopiska undersökningar. Resultaten visade att inneslutningarna bestod av sfäriska oxider och kluster uppbyggda av oxider och nitrider. Ytterligare undersökningar visade att de sfäriska inneslutningarna omvandlades från befintliga icke-metalliska inneslutningar i ferrolegeringen FeTi70R och slaggpartiklar. När det gäller kluster härrör de från desoxidationsprodukter. Vidare så bildades små inneslutningar i de lokala zonerna kring den tillsatta FeTi70R legeringen och kring titanitriderna. Undersökningarna fann också att endast Al2O3-MgO och TiN-kluster existerar efter gjutning. De industriella försöken utfördes under den sista perioden av skänkugnsbehandlingen och med en kombinerad elektromagnetisk (EMS) och gas (GS) omröring. Syftet med detta var att undersöka effekten av olika riktningar på EMS omrörningen på agglomerationen och avskiljningen av Al2O3-MgO- och TiN klustren. Undersökningarna utfördes sedan i 3D efter en elektrolytisk extraktion av metallproverna. Resultaten visar att en uppåtriktad elektromagnetisk omröring är bäst för agglomereringen av Al2O3-MgO inneslutningar och TiN kluster. Emellertid så är en nedåtriktad elektromagnetisk omröring effektivare för att avlägsna kluster från smältan. Dessa resultat överensstämmer med de teoretiska förutsägelserna baserade på Stokes, Brownian och Turbulent kollisionsvolymer. Dessutom visade beräkningarna att för Al2O3-MgO kluster med storlekar <20 μm är det turbulenta kollisioner som är den avgörande faktorn för agglomerering. Dock är det både Stokes och de Turbulenta kollisionerna som dominerar för större inneslutningar. För TiN klustren är det de turbulenta kollisionerna som är den dominerande faktorn. Ytterligare undersökningar med fler charger av Alloy 825 och olika omrörningsmetoder gjordes baserade på 2D mikroskopiska undersökningar. Mer specifikt så bestämdes antalet, storleken, sammansättningen och morfologin för olika inneslutningar med användning av SEM i kombination med EDS och Inca Feature analyser. Resultaten visar att en nedåtriktad EMS i kombination med ett gasflöde på 0,04 m3 min-1 främjar ett generellt avlägsnande av Al2O3-MgO och TiN inneslutningar. Vidare främjar den uppåtriktade EMS omrörningen en drastisk ökning av inneslutningar med en ekvivalent storlek av 11,2 μm eller mindre. Vidare har omröringen med ett gasflöde på 0,02 m3 min-1 en bättre avskiljningshastighet för inneslutningar i både nedåt och uppåtgående omrörningsriktningar jämfört med omrörningen med ett gasflöde på 0,04 m3 min-1. Emellertid kunde inget inflytande på sammansättningen och morfologin ses från de olika omrörningssätten.
QC 20171122
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Leroy, Marc. "La sidérurgie ancienne en Lorraine avant le Haut Fourneau : étude du développement historique et des conditions techniques de l'utilisation du minerai oolithique lorrain (La Minette) en metallurgie de réduction directe." Besançon, 1993. http://www.theses.fr/1993BESA1020.
Full textAbstract:
Cette étude aborde la question de l'utilisation de minerai calcaire et phosphoreux en sidérurgie ancienne, antérieurement à l'apparition des hauts fourneaux. La mise en œuvre d'une recherche pluridisciplinaire, à double approche archéologique et archéométrique, met en lumière l'utilisation du minerai sédimentaire oolithique de lorraine centrale (la minette), dès l'époque antique, préférentiellement à un minerai de surface en grains pourtant plus riche en fer. La genèse et les modalités du programme de recherche, les bases documentaires, sont replacées dans le cadre des recherches développées en pale métallurgie du fer au sein d'un vaste programme fédératif, France et l'est (chapitre 1). L'inventaire des vestiges miniers et métallurgiques répertoriés (221 sites) permet d'évaluer l'état et l'importance de la documentation archéologique. Les analyses chimiques de déchets de production (290 échantillons de minerais et scories) permettent de relier les ateliers de réduction au type de minerai utilisé (chapitre 2). Un long développement est consacré à l'étude des conditions techniques de la réduction du minerai oolithique, à travers l'apport de l'étude archéologique, chimique et métallographique des vestiges de trois ateliers de réduction fouilles. Des données sur la réductibilité du minerai, la fusibilité de sa gangue, la marche des bas fourneaux et le rendement en fer sont ainsi rassemblées (chapitre 3). Un ensemble de vestiges (structures de combustion et déchets de production) associés majoritairement à des contextes d'habitat permet d'introduire le débat sur l'identification des étapes de travail qui suivent la réduction du minerai et aboutissent à la fabrication des objets. Des éléments de réponses sont apportés (chapitre 4). L'étude se termine par un tableau synthétique et novateur de l'évolution historique de cette sidérurgie ancienne en lorraine, depuis l'époque gauloise jusqu'à la fin du moyen âge. La date d'apparition du procédé indirect est discuté en confrontant sources historiques et archéologiques (chapitre 5).
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Pateyron, Bernard. "Contribution a la realisation et a la modelisation de reacteurs plasmas souffles ou transferes appliques a la metallurgie extractive et a la production de poudres ultrafines metalliques ou ceramiques." Limoges, 1987. http://www.theses.fr/1987LIMO0030.
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Faux-Mallet, Marie-Sabine. "Extraction du gallium(iii) en milieu acide : comparaison des methodes d'extraction liquide-liquide et d'echange d'ions sur resines." Paris 6, 1988. http://www.theses.fr/1988PA066234.
Full textAbstract:
Comparaison des avantages et des inconvenients de l'extraction a l'aide de resines et de l'extraction liquide-liquide en vue de preciser leur domaine respectif d'utilisation en hydrometallurgie. Etude de la separation du gallium contenu dans les solutions d'attaque des minerais de zinc. Utilisation de la resine duolite es467 et pour l'extraction liquide-liquide de l'hydroxy-8 quinoleine et d'une alpha-hydroxy-oxime
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Adipuri, Andrew Materials Science & Engineering Faculty of Science UNSW. "Chlorination of Titanium Oxycarbide and Oxycarbonitride." Publisher:University of New South Wales. Materials Science & Engineering, 2009. http://handle.unsw.edu.au/1959.4/44405.
Full textAbstract:
The project undertook a systematic study of chlorination of titanium oxycarbide and oxycarbonitride with the aim to develop further understanding of kinetics and mechanisms of the chlorination reactions. The project studied titania, ilmenite ores, and synthetic rutile reduced by carbon in argon and nitrogen and chlorinated at different temperatures, gas flow rates and compositions. Chlorination of titanium suboxides, iron and impurities in ilmenite was also examined. Chlorination of titanium oxycarbide Ti(O,C) or oxycarbonitride Ti(O,C,N) can be implemented at 200 to 400 deg.C, while the commercial chlorination process in the production of titanium metal or titania pigment requires 800 to 1100 deg.C. This makes chlorination of Ti(O,C) or Ti(O,C,N) an attractive technology in processing of titanium minerals. Chlorination reaction is strongly exothermal, which increased the sample temperature up to 200 deg.C above the furnace temperature. The chlorination of Ti(O,C) or Ti(O,C,N) was ignited at 150 deg.C to 200 deg.C depending on the sample composition. Their chlorination at 235 deg.C to 400 deg.C was close to completion in less than 30 min. The chlorination rate of titanium oxycarbide or oxycarbonitride increased with increasing gas flow rate. Sample composition had a significant effect on the extent of chlorination. The optimum results were obtained for titanium oxycarbide or oxycarbonitride produced with carbon to titania molar ratio of 2.5; these samples contained no detectable excess of carbon or unreduced titanium suboxides. In chlorination of reduced ilmenite ores and synthetic rutile, Ti(O,C) or Ti(O,C,N), metallic iron and Ti2O3 were chlorinated. The rate and extent of chlorination of titanium increased with increasing carbon to TiO2 ratio. Chlorination of Ti2O3 was slow relative to Ti(O,C) or Ti(O,C,N) and iron; chlorination of impurity oxides such as MgO, SiO2 and Al2O3 was not observed. The project also examined chlorination of Ti(O,C) or Ti(O,C,N) in ilmenite ore and synthetic rutile after removal of iron, which was achieved by aerated leaching of reduced samples in heated flask containing 0.37 M of ammonium chloride solution. Iron removal from the ilmenite ore or synthetic rutile resulted in higher rate and extent of chlorination of titanium oxycarbide or oxycarbonitride.
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Danard, Yolaine. "Développement d'alliages de titane transformables par déformation : étude des relations microstructure/propriétés mécaniques." Thesis, Paris Sciences et Lettres (ComUE), 2019. http://www.theses.fr/2019PSLEC035.
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Le travail concerne le développement de nouveaux alliages de titane possédant des propriétés uniques de déformation plastique (une ductilité près de 3 fois supérieure aux alliages classiques) et d’écrouissage. Un travail initial (Bourse CIFRE de Cédrik Brozek, 2013-2016) a permis de transposer des approches utilisés initialement sur des alliages modèles (Ti-Mo en particulier), à des matériaux potentiellement industrialisables en vue d’applications dans le domaine de l’aéronautique. C’est sur ces nouvelles nuances industrialisables, basées sur le système Ti-Cr-Sn que nous souhaitons aujourd’hui faire reposer la collaboration avec notre partenaire industriel. Ces alliages possèdent la capacité à se transformer sous contrainte, par maclage mécanique et transformation de phase induite, ils possèdent une combinaison de propriétés inédite (une ductilité très importante accompagnée d’un écrouissage non encore atteint dans les alliages de titane) mais ils se caractérisent aussi par une complexité microstructurale très élevée sur laquelle nous ne possédons que peu d’information pour le moment. L’objet de la présente demande porte donc sur l’étude des relations microstructures/propriétés mécaniques dans cette nouvelle famille d’alliages de titane (les alliages "TRIP/TWIP")The work concerns the development of new titanium alloys possessing unique properties of plastic deformation (distortion) (a ductility near 3 times superior to the classic alloys) and work hardening. An initial work (CIFRE PhD of Cédrik Brozek, 2013-2016) allowed to transpose approaches used initially on model alloys (Ti-Mo in particular), in materials potentially industrialisables with the aim of applications in the field of the aeronautics. It is on these new industrialisables nuances, based on the system Ti-Cr-Sn that we wish today to base the collaboration with our industrial partner. These alloys possess the capacity to be transformed under constraint, by maclage mechanics and transformation of induced phase, they possess a new combination of properties (a very important ductility accompanied with a work hardening not yet reached in the alloys of titanium) but they are also characterized by a very high microstructural complexity on which we don't possess that much informations for the moment. The project concerns the study of the relations microstructures / mechanical properties in this new family of titanium alloys (alloys "TRIP/TWIP")
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Tchoumou, Martin. "Hydrometallurgie du cuivre en milieu chlorure : attaques de minerais dosages polarographiques des solutions resultant de l'attaque et depot cathodique du cuivre." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13154.
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Etude dans le cadre de l'extraction de cu des minerais de type chalcopyrite. Lors de l'attaque des minerais de type chalcopyrite par des solutions de cu(ii) en milieu fortement chlorure, les metaux presents dans le minerai sous forme de sulfures passent en solution soit partiellement soit en totalite, et s elementaire precipite. Mise au point du dosage polarographique des ions cu, pb, zn et fe dissous. L'electrolyse de solutions a teneur elevee en cu(i) et contenant pb(ii), zn(ii) ou fe(ii) a mis en evidence un phenomene de codeposition de pb avec cu lorsqu'on opere a des densites de courant elevees, tandis que ni zn ni fe ne se codeposent avec cu
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Lamirault, Sylvie. "Comportement du cuivre dans les melanges hf-mf (m = k ou nh : :(4)) fondus utilises pour l'obtention electrolytique du fluor." Paris 6, 1987. http://www.theses.fr/1987PA066467.
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Etude thermodynamique et cinetique de la corrosion electrochimique dans les melanges hf-mf(m=k ou nh::(4)) du cuivre metal entrant, soit pur, soit sous forme d'alliage (monel) dans la construction des cellules industrielles d'electrolyse. Mise en evidence de la formation d'une couche de fluorure de cuivre passivante. Evaluation de l'epaisseur limite de la couche. Etablissement de l'influence de la densite de courant sur le caractere passivant de la couche formee. Proposition d'un mecanisme de corrosion du cuivre
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Cocksedge, Mark Burden. "Extraction of platinum, palladium and rhodium from tailings by a metal chloride based leach reagent." Thesis, 1993. http://hdl.handle.net/10539/22835.
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A Dissertation submitted to the Faculty of
Engineering, University of the Witwatersrand
Johannesburg, in fulfillment of the requirements for
the Degree of Master of Science in EngineeringHigh extractions of the platinum group metals' from a refractory tailings concentrate (PGM Concentration : Pt 81.5ppm, Pd 21.5ppm, Rh 17.5ppm) was achieved after short. low-temperature roasting and subsequent leaching with a zinc chloride based leach reagent containing nitric acid under atmospheric pressure at temperatures from 105-C to 120-C. [Abbreviated Abstract. Open document to view full version]
AC2017
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Fosso-Kankeu, Elvis. "Ni²⁺ extraction from low grade leachate of tailing dumps materials using cloned indigenous bacterial species." Thesis, 2012. http://hdl.handle.net/10210/8033.
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Ramakanth, C. "Studies On Copper Extraction With 5-Dodecylsalicyl Aldoxime In Supported Liquid Membranes." Thesis, 1996. http://etd.iisc.ernet.in/handle/2005/1864.
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Rolfe, Wesley. "Development of a high pressure hydrometallurgical process for the extraction of iron from iron oxide bearing materials." Thesis, 2016. http://hdl.handle.net/10539/22608.
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A dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, in fulfilment of the requirements for the degree of Master of Science in Engineering.
Johannesburg, 2016The feasibility of extracting iron from iron(III) oxide bearing materials with acetylacetone has been under investigation for many years. This is an alternate, environmentally friendly process for the recovery of iron compared to conventional processes that are energy intensive, have numerous costly process steps and produce large quantities of greenhouse gases. Iron(III) oxide bearing waste materials can be used in this process which reduces its environmental impact as it would not require waste storage. This study investigated the feasibility of reducing the reaction time of the liquid phase extraction of iron from iron ore fines by performing the extraction at elevated pressures and temperatures. It was found that that the extraction under pressure was dependent on temperature, pressure, particle size and solid to liquid ratio. It was found that at high temperatures and long extraction times, an unknown secondary reaction occurs that consumes the desired product, iron(III) acetylacetonate, and inhibits the recovery of these crystals. This results in lower extraction yields. It was found that the side reaction was largely dependent on the temperature of the system and the amount of iron(III) acetylacetonate present. The effects of the side reaction could be limited by lower operating temperatures and reducing the total reaction times. An optimum conversion of iron(III) oxide to iron(III) acetylacetonate of 47.2% was achieved for synthetic iron (III) oxide (> 95 wt% Fe2O3) at a total extraction time of 4 h, 160 °C, 0.025 g:1 mL, operating pressure of 1700 kPa, initial N2 feed pressure of 1010 kPa and 375 rpm stirrer speed. The optimum extraction of iron from iron ore fines (> 93 wt% Fe2O3) to iron(III) acetylacetonate was found to be 20.7% at 4 h, 180 °C, 0.025 g:1 mL and operating pressure of 1900 kPa, initial N2 feed pressure of 1010 kPa and 375 rpm stirrer speed. These are the optimum conditions where the side reaction is limited to improve the recovery and desired reaction conversion capabilities of the process. The operation under pressure yielded lower conversions than that of the atmospheric leaching process developed by Tshofu (acetylacetone water system under reflux). It was also found that it was not possible to reduce the extraction time and achieve comparable extractions when operating at higher temperatures and pressures. The formation of an additional unwanted product would also lead to unnecessary treatment costs in an industrial process. Hence, it was found that pressure leaching as an alternative is not currently viable due to the lower yields and associated high costs. Atmospheric leaching seems to be the most economically feasible option until a better alternative is found.
MT2017
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Ralebakeng, Thato. "Stability of the ferrosilicon heavy medium for value recovery from synthetic, kimberlitic and alluvial diamond ores." Thesis, 2012. http://hdl.handle.net/10210/4831.
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M. Tech.The separation of minerals such as coal, diamonds and others have involved the use of a heavy medium. The heavy medium separation technique, used in the diamond industry as a primary concentrator, is a physical process that separates minerals of different specific densities based on their relative movement and resistance to motion in a viscous fluid. It is made up of a suspension of finely ground solid particles constituting a stable suspension. There is a wide range of materials that are used to prepare suspension media in Heavy Medium Separation (HMS), but Ferrosilicon has found a wider usage. Major demand for dense medium Ferrosilicon powder is from the diamond industry which accounts for 77 percent of milled sales. In HMS, either dynamic or static separators can be used, even though; dynamic separators are widely used because they give higher separation efficiencies. A number of accounts have been reported on the effects of stability and viscosity to the medium. It is, however, observed that the effect of ore mineralogy, which is a major contributing factor during ore and medium interaction, during separation, has not been properly taken into account, apart from the fact that ore mineralogy form a basis for HMS efficiency. The literature, however, does not cover a thorough investigation of the relationship between the recovery of diamond bearing ores and stability of Ferrosilicon grades media, as a function of physicochemical properties of ferrosilicon. Eight samples of Ferrosilicon, four milled and four atomized were used to prepare media to recover value from kimberlitic ore, alluvial ore and synthetic ore in a laboratory set-up HMS. Both Ferrosilicon and ore samples were characterized with the following techniques before use: XRD, XRF, SEM-EDAX and Screening, to investigate physico-chemical properties of ferrosilicon and ore mineralogy. The used Ferrosilicon was also characterized to investigate any v changes as Ferrosilicon medium interacted with the ores. Settling tests were performed on each Ferrosilicon grade to investigate media stability before and after recovery exercise. The stability of the media was then related to the recovery of each ore. In-circuit sample of ferrosilicon was collected from Letšeng diamonds to compare any changes with Ferrosilicon used in the laboratory, and also used to study the effects of contamination on the degradated medium. All recovery results were done in a static HMS, but in practice dense medium cyclones are widely used. The screening characterization technique revealed that there was a loss of finer particles size fraction, predominant in sieves 75 microns and 45 microns and that loss was highest with atomized grades than milled ferrosilicon grades. Minimal changes in density and chemical compositions were observed for each ferrosilicon grade. The loss of the finer fraction was found to effect changes in the settling rate of each ferrosilicon grade differently, hence changes in the stability of their media. The efficiency (Ep) of separation was found to vary with each grade of Ferrosilicon used, accompanied by a shift in cut point density indicating the influence of grade on the separation efficiency. The effects of medium stability on recovery for both ores showed that although both ores percentage recoveries differ, the trend of medium stability to recovery, with each Ferrosilicon grade, is the same. However, the recovery was found to be more dependent on the density of the medium, as the effects of loss of finer particle size fraction did not show any significant contribution to recovery, but rather on the medium loss. The mineralogy of the ores also had been observed to give a minimal or no contribution to the separation efficiency, if related to recovery. Milled Ferrosilicon is further recommended over atomized Ferrosilicon, based on cost and stability. The highest loss of atomized Ferrosilicon could escalate the operating costs and affect the stability of the medium. It should be remembered that the purchasing costs of atomized grades is higher than that of milled grades.
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Lindvall, Mikael. "A Study on Vanadium Extraction from Fe-V-P Melts Derived from Primary and Secondary Sources." Doctoral thesis, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-213747.
Full textAbstract:
Vanadium extraction methods were developed for iron-vanadium-phosphorus (Fe-V-P) melts derived from processing of V-bearing titanomagnetites and steel slags. Studies on phase relationships of V slags were carried out to provide important understanding of the extraction processes. Phase relationship in vanadiferous slag was investigated experimentally at 1573K, 1673K and 1773K, for the compositional range of 0-6mass% Al2O3, 1-5mass% CaO, 10-17mass% SiO2, with MnO and V2O3 fixed at 5.5mass% and 30mass%, balanced with FeO. The slags were found to be solid-liquid mixtures, of liquid, spinel and in some cases free silica. Alumina was identified as the preferred additive to prohibit precipitation of free silica. A method for V extraction to vanadiferous slag was developed based on Fe-V(2mass%)-P(0.1mass%) melts at 1677K using a semi-industrial scale BOF. Oxidation was carried out with an oxygen enriched air jet and iron ore pellets. The complete dissolution of pellets was achieved by deliberately creating good stirring conditions utilising high momentary decarburisation rates. The P distribution to the slag was low when good stirring conditions was obtained. Phase relationship in Al2O3-CaO(25-35mass%)-SiO2-VOx slag was investigated experimentally at an oxygen partial pressure of 9.37•10-11atm and 1873K. The maximum solubility of V-oxide in the slag was 9-10mass% V2O3. Two solid phases were found, a solid solution of Al2O3 in V2O3 (karelianite) and hibonite with fractionation of V into the crystal structure. V extraction experiments to Al2O3-CaO-SiO2 based slags were carried out in 150kg scale by blowing CO2 gas into the metal bath consisting mainly of 1-10mass% V and 1mass% P. At these conditions, oxidation of V was favoured over Fe. Up to 10-13mass% V2O3 could be dissolved in the slag before a viscous slag saturated in V-oxide was observed. The phosphate capacity in the slag was low and as a result this slag could at once be subjected to a final reduction step for production of ferrovanadium with 40-50mass% V.Metoder för att utvinna vanadin till högvärdiga vanadinslagger från metallsmältor innehållande främst järn (Fe), vanadin (V) och fosfor (P) utvecklades. Metallsmältorna framställs genom att processa primära V råvaror, såsom titanomagnetit, och sekundära råvaror av i huvudsak vanadinrik stålslagg. Fasstudier av högvärdiga vanadinslagger genomfördes som grund för utvecklingsarbetet. Experimentella fasstudier av vanadinspinellslagg med 30vikt% V2O3 och 5.5vikt% MnO genomfördes vid en temperatur av 1573K, 1673K och 1773K. Övriga komponenter i slaggen varierades inom ett intervall av 0-6vikt% Al2O3, 1-5vikt% CaO och 10-17vikt% SiO2, viktad med järnoxid. Samtliga slagger var sammansatt av både flytande- och fastfas. Den fasta fasen utgjordes främst av en vanadin- och järnrik spinellfas och i vissa fall även av fri SiO2. Genom försök i en stålkonverter i semi-industriell skala utvecklades och validerades en metod för vanadinutvinning från råjärnsmältor innehållande 2vikt% V och 0.1vikt% P, vid en temperatur av 1677K. Oxidationen utfördes med syreanrikad luft via en vattenkyld topplans och genom tillsats av hematit pellets. Omsättningen av pellets säkerhetsställdes genom god omrörning som erhölls under korta perioder med höga gasvolymer som en effekt av hög avkolningstakt. Råjärnet efter behandlingen innehöll cirka 3vikt% C och 0.1vikt% V. Producerad vanadinspinellslagg bestod av upp till 30vikt% V2O3. Fosforfördelningen till slaggen var låg under processbetingelser med god omrörning. Experimentella fasstudier av Al2O3-CaO(25-35vikt%)-SiO2-VOx slagg genomfördes vid en temperatur av 1873K och ett syrepartialtryck av 9.37·10-10atm. Den maximala lösligheten av vanadinoxid i slaggen var 9-10vikt% V2O3. Två fasta faser identifierades, V2O3 (Karelianit) med fast löslighet av Al2O3 och Hibonit med vanadinoxid inlöst i kristallstrukturen. Experimentella försök för att utvinna vanadin från en stålsmälta bestående av 1-10vikt% V och 1vikt% P till en slagg med en initial sammansättning av 7-40vikt% Al2O3, 25-35vikt% CaO och 27-64vikt% SiO2 utfördes i en skala av 150kg. Oxidation av vanadin åstadkoms genom att blåsa in CO2 gas i stålsmältan via en spolsten. Under dessa processförhållanden var oxidationen av vanadin gynnsam framför järn och fosfor. Lösligheten av vanadinoxid i slaggen var upp till 10-13vikt% V2O3. Slagg mättad med vanadinoxid var viskös som en konsekvens av utfällning av V2O3 med inlöst Al2O3. Slaggens gynnsamma vanadin och järn- samt vanadin och fosfor förhållande möjliggör att genom slutreduktion producera ferrovanadin med en vanadinhalt av 40-50vikt% och låg fosforhalt.
QC 20170912
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Kitungwa, Kabezya. "Study of dispersion phenomenon in Creusot Loire Uddeholm reactor." Thesis, 2009. http://hdl.handle.net/10539/6860.
Full textAbstract:
A study on the slag dispersion in bath smelting converter was undertaken. The aim
was mainly to investigate the behaviour of the dispersed slag phase at high gas flow
rate and low slag volume (10%) systems. For simulations purposes, water; paraffinoil
and air were used in a one fifth model of the commercial 100 ton Creusot-Loire-
Uddeholm converter to represent bulk steel, molten slag and gas respectively.
Emulsion samples were collected by means of the specially made syringe. The
experimental results revealed that the dispersed slag phase decreased with the vertical
distance from the original interface between the liquid phases. The dispersed phase
decreased also with the radial distance in the water plume zone towards the wall side.
The holdup was apparently much observable on the right side than on the left side.
Four dimensionless numbers defined the dispersion phenomenon through the
dimensional analysis. The modified Froude Number ensured the correlation between
both model and prototype. The standard error of the estimate and R-squared between
the experimental and the calculated results were 3.7 ´10-4 and 0.97 respectively.
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de, Bakker Jan. "The recovery of magnesium oxide and hydrogen chloride from magnesium chloride brines and molten salt hydrates." Thesis, 2011. http://hdl.handle.net/1974/6337.
Full textAbstract:
Hydrochloric acid leaching of saprolite nickel ores has been proposed as an effective means of recovering nickel and cobalt. However, the leach produces a concentrated brine of magnesium chloride which must be hydrolyzed to recover the HCl lixiviant. The processing of carnallite similarly produces a concentrated MgCl2 brine; converting this brine into HCl and MgO provides an attractive way of adding value while effectively disposing of this waste product.
Direct pyrohydrolysis of magnesium chloride brines by the reaction,
MgCl2,a + H2Oa MgOs + 2HClg
is energy-intensive as large volumes of water must be evaporated. The energy cost is high, and the HCl stream produced is limited to approximately 20 wt% HCl. This thesis explores alternative methods of obtaining HCl from aqueous magnesium chloride solutions. Two methods are considered: the hydrolysis, under autogenous pressure, of concentrated MgCl2 molten salt hydrates; and the precipitation of magnesium hydroxychloride compounds such as 2MgO·MgCl2·6H2O and 3MgO·MgCl2·11H2O, which are subsequently decomposed at high temperature.
Considerable experimental difficulties were encountered in studying pressure hydrolysis of molten salt hydrates, despite extensive equipment modifications. Ultimately, the work moved on to precipitation and decomposition of hydroxychlorides. This was found to bear promise, and conceptual flowsheets based on these reactions are presented. A phase stability diagram giving the areas of predominance of the different hydroxychloride phases is presented, and fundamental thermochemical data are derived. The results of a kinetic study on magnesium hydroxychloride thermal decomposition are also presented.Thesis (Ph.D, Mining Engineering) -- Queen's University, 2011-03-11 10:14:53.455
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Thobakgale, Rendani. "Evaluation of the geochemical and mineralogical transformation at an old copper mine tailings dump in Musina, Limpopo Province, South Africa." Diss., 2017. http://hdl.handle.net/11602/931.
Full textAbstract:
MENVSCDepartment of Ecology and Resource Management
Historically, mining activities have generated vast quantities of abandoned tailings dumps in several regions of South Africa and throughout the world. The management and disposal of huge volumes of tailings dumps has constituted a major challenge to the environment. The current study aims to establish the physicochemical properties and mineralogical characterization of the old copper tailings dump in Musina, to reveal the mobility patterns and attenuation dynamics of potentially toxic or heavy metal species as a function of depth, with a view of assessing their potential environmental impact with respect to surface and ground water systems. This information is crucial in the beneficial utilization of copper tailings in the development of sustainable construction materials as part of reuse approach management system. About twelve tailings samples were collected into polyethylene plastic bags from three established tailings profiles drilled by a hand auger. The collected tailings samples were characterized using standard analytical procedures i.e., X-ray fluorescence (XRF), X-ray diffraction (XRD) and scanning electron microscopy/energy dispersive spectroscopy (SEM-EDS). The transfer of potentially toxic or heavy metal species from tailings to water was evaluated using the standardized batch leaching test (EN 12457) and speciation-equilibrium calculations on the aqueous extracts performed by MINTEQA2. The leachate concentration of cations in the collected tailings samples was determined by inductively coupled mass spectrometry (ICP-MS) and the leachate concentration of anions was determined by ion chromatography (IC). A modified sequential extraction scheme was applied on the selected tailings samples of the drilled tailings profiles to further understand the mode of occurrence, the geochemical partitioning and distribution, real mobility, and environmental bioavailability of potentially toxic or heavy metal species in the tailings and tailings-soil interface. The extracted fractions or phases from sequential scheme were as follows: (F1) water-soluble fraction, (F2) exchangeable fraction, (F3) carbonate fraction, (F4) iron and manganese hydroxide associated fraction, (F5) organic matter and secondary sulphide associated fraction, (F6) primary sulphide bound fraction, and (F7) residual or silicate fraction. The results obtained from the seven steps sequential extraction scheme were validated by the determination vi of percentage recoveries from pseudo-total digestion or total metal content of the original sample. The distribution of major elements and potentially toxic or heavy metal species in different leachate fractions obtained after each step of sequential extraction of the selected tailings samples was determined by inductively coupled plasma mass spectrometry (ICP-MS). The appraised data was used to reveal the impact of atmospheric oxygen and infiltrating rain-water on the chemistry of copper tailings dump by depth profiles. Macroscopic properties revealed that the abandoned Musina copper tailings are fine to medium coarse grained, and range in color from light/dark gray at the upper or shallow depth of the tailings, to dark reddish-brown at the deeper zone where the tailings are mixed with the underlying soil or soil-interface. The drilled respective tailings profiles were uniform and slightly varied in both mineralogical and bulk chemical compositions with tailings depth. Mineralogical analysis showed the following order of mineralogical composition within the respective tailings profiles: quartz> epidote> chlorite> muscovite> calcite> hematite. Chalcopyrite was the only sulphide mineral observed by optical microscopy, although not identified or quantified by XRD and SEM-EDS analysis. The observed discrete chalcopyrite grains were attributed to the primary mined ore (i.e., chalcopyrite, chalcocite and bornite) during past copper mining activities in Musina. The tailings profiles were characterized by a medium alkaline pH (7.97-8.37) that corresponds very well with the tailings leachates or pore-water pH (8.36-8.46). This pH was constant and slightly varied with tailings depth in the respective tailings profiles. The high abundance of alumino-silicate minerals and traces of carbonates as calcite coupled with low sulphide mineral content, suggested a high neutralization capacity of the tailings which was in common agreement with an alkaline nature of the copper tailings dump. The chemical composition of major elements within the respective tailings profiles followed the order: Si>Al>Fe>Ca>Mg>K>Na, and corresponds very well with the mineralogical composition of the tailings, whereby alumino-silicates were the most abundant minerals in the tailings samples. Nevertheless, the solid-phase concentration of metals decreases with increasing tailings depth as Cu>Sr>Zr>Ni>Zn and was incongruent with the mineralogical composition within the respective tailings profiles. The main secondary minerals were calcite and hematite, and their proportion increased with increasing tailings vii depth. In addition, hematite formed coatings on the rims and corners of chlorite as observed from optical microscopy, and retained relatively high amounts of potentially toxic or heavy metals (up to 862 ppm of Cu, up to 36 ppm of Ni, and up to 25 ppm of Zn) at the upper and shallow depth of the respective tailings profiles, where bulk density was high and low porosity. Based on batch leaching tests, the amounts of potentially toxic or heavy metal species released into solution were low (0.27-0.34 μg/L Pb, 0.54-0.72 μg/L Ni, 0.88-1.80 μg/L Zn, and 20.21-47.9 μg/L Cu) and decreases with increasing tailings depth, indicating that, presently, the tailings have a minor impact on heavy metals load transported to the receiving surface and groundwater systems. The low concentration of potentially toxic or heavy metal species in solution is primarily due to their retention by secondary Fe oxide phases (i.e., hematite) and the prevailing medium alkaline pH condition of the tailings leachate or pore-water. The observations are consistent with MINTEQA2 speciation calculations, which predicted the precipitation of secondary phase cuprite (Cu2O) as the main solubility-controlling mineral phase for Cu, Zn, and Ni. Primary factors influencing aqueous chemistry at the site are neutralization and dissolution reactions as a function of pH, precipitation, and sorption into hydrous oxides (hematite and cuprite). Based on sequential extraction results, the leachable concentration of potentially toxic or heavy metal species in the water-soluble, exchangeable and carbonate fractions of the respective tailings profiles was relatively low, except for Cu and Mn. For instance, the leachable concentration of Cu and Mn reached 10.84 mg/kg and 321.7 mg/kg at the tailings-soil interface (3 m) in tailings profile C, respectively. The low concentration of potentially toxic or heavy metal species (Cr, Co, Ni, Zn, Cd, and Pb) in these fractions could be due to the low solubility of minerals bearing these trace elements caused by variations in pore-water pH in the respective tailings profiles. The high concentration of Cu and Mn in these fractions suggests their high mobility and therefore most available for uptake in the environment. Except for Cu>Mn>Cr, the contents of potentially toxic or heavy metal species in the Fe and Mn oxides and organic matter or sulphides bound fractions was low, due to the low viii quantity of these fractions in the tailings, despite their high affinity and sorption capacity for potentially toxic or heavy metal species. Likewise, the residual fraction of the respective tailings profiles contained the highest proportion of potentially toxic or heavy metal species. Although the highest potentially toxic or heavy metal species content was in fractions with limited mobility, care must be taken since any geochemical change or shift in the tailings pH or acidic conditions may cause them to be displaced to more mobile fractions, thereby increasing their mobility and environmental bioavailability. Therefore, physicochemical properties of the tailings including pH and mineralogical composition of the tailings samples were the main substrate controlling the geochemical partitioning and distribution, potential mobility, and environmental bioavailability of potentially toxic or heavy metal species by tailings depth. The knowledge of mobility and eco-toxicological significance of tailings is needed when considering tailings dump disposal or reuse in the environment. The addition of copper tailings at 3 and 28 days successfully improved the compressive strength of cement mortar mixtures incorporating tailings at C5 (5%) and C10 (10%) respectively, although with small margin relative to the control mixture (C0). The maximum strength was 31.15 Mpa attained after 28 curing days, and slightly varied when compared with other compressive strength on copper blended cement mortars mixtures in other countries, used for the development of sustainable construction materials. The chemical composition, physical properties and improved compressive strength on cement mortars mixtures incorporating copper tailings, implies that copper tailings are suitable for the development of sustainable construction materials, thereby ensuring job creation, availability of land for development usage, and the reduction of environmental pollution induced by the abandoned copper tailings dumps.