Journal articles: 'Metal Extraction'

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Cuculovic, Ana, Mirjana Pavlovic, Dragan Veselinovic, and Scepan Miljanic. "Metal extraction from Cetraria islandica (L.) Ach. lichen using low pH solutions." Journal of the Serbian Chemical Society 73, no. 4 (2008): 405–13. http://dx.doi.org/10.2298/jsc0804405c.

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Extraction of metals (K, Al, Ca, Mg, Fe, Cu, Ba, Zn, Mn and Sr) from dry Cetraria islandica (L.) Ach. lichen was performed using solutions similar to acid rain (solution A H2SO4-HNO3-(NH4)2SO4 and solution B H2SO4- -HNO3-(NH4)2SO4-NH4NO3). The pH values of these solutions were 2.00, 2.58, 2.87, 3.28, and 3.75. Five consecutive extractions were performed with each solution. In all solutions, the extracted metal content, except Cu and Ca, was the highest in the first extract. The highest percentage of the metals desorbed in the first extraction was obtained using solutions with low pH values, 2.00, 2.58, and 2.87. The lowest percentage in the first extraction was obtained using solutions with pH 3.28 and pH 3.75, indicating influence of the H+ ion on the extraction. According to the results obtained, the investigated metals form two groups. The first group includes K, Al, Ca, Mg, and Fe. They were extracted in each of the five extractions at each of the pH values. The second group includes Ba, Zn, Mn, Cu, and Sr, which were not all extracted at each pH value. The first group yielded three types of extraction curves when the logarithms of extracted metal amounts were plotted as a function of the number of successive extractions. These effects indicate that three different positions (centers) of metal ion accumulation exist in the lichen (due to sorption, complex formation, or other processes present in the tissues).

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Junussov, Medet, Ferenc Mádai, and Bánhidi Olivér. "Sequential extraction of carbonaceous siltstone rock for multi-element analysis by ICP OES." Contemporary Trends in Geoscience 7, no. 2 (December 1, 2018): 145–52. http://dx.doi.org/10.2478/ctg-2018-0010.

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Abstract The carbonaceous siltstone rock material is a disseminated sulfide-rich sedimentary rock from a sediment-hosted gold deposit of Bakyrchik. The Bakyrchik deposit is located in Eastern Kazakhstan, which includes in Qalba gold province. The main purpose of this paper is a demonstration on chemical extraction of heavy metals from the carbonaceous siltstone rock and detection of its elemental concentrations. In the work was used a rock sample from the deposit which is a sericizited carbonaceous-siltstone rock. In sequential extraction method was selected four stages such as water soluble fraction (reaction with deionized water) for extraction of water soluble metals, reducible metal fraction (reaction with hydroxyl ammonium chloride) for extracting all reducible metals, organics and sulfides (reaction with hydrogen peroxide) for dissolution of organics and copper sulfide, and extraction of metal oxides and residual fraction (reaction with aqua regia) for extracting of all remaining metals. The paper comprises analytical methods for research outlooks. They are X-Ray Diffraction (determination of mineralogical composition), X-Ray Fluorescence (determination of chemical composition) and Inductively Coupled Plasma – Optical Emission Spectrometry (determination of heavy metal concentrations).

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Marchi, Giuliano, Luiz Roberto Guimarães Guilherme, Andrew C. Chang, and Clístenes Williams Araújo do Nascimento. "Heavy metals extractability in a soil amended with sewage sludge." Scientia Agricola 66, no. 5 (October 2009): 643–49. http://dx.doi.org/10.1590/s0103-90162009000500009.

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Few investigations have been carried out about the comparison of desorption rate and amount of heavy metals extracted successively by organic acid mixtures mimicking the rhizosphere and routine extractants in sewage sludge-amended soils. Extractions of Zn, Cd, Ni, Cr, and Cu were performed in samples of a sewage sludge-amended soil using seven extractants: four organic acid mixtures and three routine extractants (DTPA, Mehlich-I, and ammonium acetate). Results from single pass extractions, in which the extractable metal contents were determined by simply extracting the soil a single time, as well as from 15 successive extractions, in which the solid residues of the first extraction was successively extracted 14 additional times, of heavy metals were analyzed. The extractability of heavy metals in a single pass extraction was, in general, as follows: Mehlich-I > DTPA > organic acids > NH4OAc. The highest rates of extraction followed the general order: DTPA > Mehlich-I > organic acids > NH4OAc. While Mehlich-I presented the highest extractability of heavy metals among studied extractants, DTPA showed a high extractability of Zn, Cd, Ni, and Cu in a single extraction as well as the highest rates of extraction among the studied extractants. The transfer of heavy metals from soil to organic acid solutions is slower than to DTPA and Mehlich-I extractants.

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Shaikh, S. M., R. U. Shaikh, and A. B. Ade. "Protein Profiling of Thiobacillus ferrooxidans and Pseudomonas fluorescens Mutants during Metal Extraction." Journal of Scientific Research 10, no. 1 (January 1, 2018): 61–66. http://dx.doi.org/10.3329/jsr.v10i1.33641.

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Proteins are specific for the specific task associated with the cell. The metal extracting bacteria, Thiobacillus ferrooxidans and Pseudomonas fluorescens have two different mechanisms for the metal extraction. One extracts the metals by donating electrons and by doing self-oxidation and another is accumulating the metals onto its cell surface which is negatively charged. Therefore to differentiate the task of metal extraction protein profiling was done and compared. The water soluble proteins were analyzed through SDS-PAGE. There was no significant difference in the profiles of both.

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Shyam Sunder, Govind Sharma, Sandhya Adhikari, Ahmad Rohanifar, Abiral Poudel, and Jon R. Kirchhoff. "Evolution of Environmentally Friendly Strategies for Metal Extraction." Separations 7, no. 1 (January 6, 2020): 4. http://dx.doi.org/10.3390/separations7010004.

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The demand for the recovery of valuable metals and the need to understand the impact of heavy metals in the environment on human and aquatic life has led to the development of new methods for the extraction, recovery, and analysis of metal ions. With special emphasis on environmentally friendly approaches, efforts have been made to consider strategies that minimize the use of organic solvents, apply micromethodology, limit waste, reduce costs, are safe, and utilize benign or reusable materials. This review discusses recent developments in liquid- and solid-phase extraction techniques. Liquid-based methods include advances in the application of aqueous two- and three-phase systems, liquid membranes, and cloud point extraction. Recent progress in exploiting new sorbent materials for solid-phase extraction (SPE), solid-phase microextraction (SPME), and bulk extractions will also be discussed.

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Manousi, Natalia, Dimitrios A. Giannakoudakis, Erwin Rosenberg, and George A. Zachariadis. "Extraction of Metal Ions with Metal–Organic Frameworks." Molecules 24, no. 24 (December 16, 2019): 4605. http://dx.doi.org/10.3390/molecules24244605.

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Metal–organic frameworks (MOFs) are crystalline porous materials composed of metal ions or clusters coordinated with organic linkers. Due to their extraordinary properties such as high porosity with homogeneous and tunable in size pores/cages, as well as high thermal and chemical stability, MOFs have gained attention in diverse analytical applications. MOFs have been coupled with a wide variety of extraction techniques including solid-phase extraction (SPE), dispersive solid-phase extraction (d-SPE), and magnetic solid-phase extraction (MSPE) for the extraction and preconcentration of metal ions from complex matrices. The low concentration levels of metal ions in real samples including food samples, environmental samples, and biological samples, as well as the increased number of potentially interfering ions, make the determination of trace levels of metal ions still challenging. A wide variety of MOF materials have been employed for the extraction of metals from sample matrices prior to their determination with spectrometric techniques.

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Tian, Qinghua, Xiangdong Gan, Fuhui Cui, Dawei Yu, and Xueyi Guo. "Selective Extraction of Ni from Superalloy Scraps by Molten Mg-Zn." Metals 11, no. 6 (June 21, 2021): 993. http://dx.doi.org/10.3390/met11060993.

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Bearing significant concentrations of high value and critical metals, superalloy scraps require comprehensive recycling for metal reclamation. In this study, nickel-based superalloy was treated with molten Mg-Zn for the selective extraction of nickel. The influence of heating temperature, the molar ratio of Mg to Zn in the molten metal, Mg-Zn/superalloy mass ratio, and heating time on metal extraction were investigated. Using the heating temperature of 800 °C, the Mg/Zn molar ratio of 9/1, the Mg-Zn/superalloy mass ratio of 5/1, and heating time of 240 min, the extraction rate of 97.1% was achieved for Ni, and the extraction rates of Fe, Cr and refractory metals (Nb, Mo and Ti) were all less than 1%. In the subsequent vacuum distillation process, nickel with a purity of 98.3 wt% was obtained. Therefore, the proposed method is a short, clean, and efficient process for selectively extracting nickel from the superalloy scraps.

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Sládek, Petr, Oldřich Navrátil, and Petr Linhart. "Extraction of Selected Lanthanoids and Scandium with Bis(2-ethylhexyl)hydrogenphosphate in 1,1,2,2-Tetrachlorodifluoroethane." Collection of Czechoslovak Chemical Communications 57, no. 8 (1992): 1647–54. http://dx.doi.org/10.1135/cccc19921647.

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A study was made of the extraction of Ce, Pm, Eu, Tm and Sc(III) from aqueous into organic medium of 1,1,2,2-tetrachlorodifluoroethane (CFC-112) using bis(2-ethylhexyl)hydrogenphosphate (HDEHP) as extracting reagent. On the basis of earlier work which demonstrated the usefulness of using this type of solvent for extractions with dibutylhydrogenphosphate (HDBP) and also the possibility of using CFC-112 for converting the metal chelates formed to the solid phase, the work was concentrated particularly on the dependence of the extraction of selected lanthanoids on the analytical concentration of HDEHP and also on the [H+] concentration. In addition the dimerization and distribution constants were determined for this reagent in a mixture of CFC-112 with benzene and the extraction constants were determined for the individual metals.

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Othman*, Amel Ben, Imen Ben Fredj, and Rym Abidi. "Extracting and complexing properties of di-, tri- and tetra ThiaCalix [4] arenes." International Journal of Bioassays 5, no. 10 (October 1, 2016): 4948. http://dx.doi.org/10.21746/ijbio.2016.10.007.

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In the present work, the focus is the study of complexing and extracting properties of three nanoscale derivatives namely multicalixarenes 2C, 3C and 4C which the latter structure is a dendrimer structure of first generation. The metal cations included in this study are the alkali metal, alkaline earth metal, some transition metals, heavy metals and lanthanides. This study was conducted essentially in methanol to determine the stoichiometry of the complexes formed, or the location of the coordination sites, and finally to evaluate selectivity's. These studies have been conducted by UV-visible spectrophotometry, conductivity and proton NMR. The liquid-liquid extraction picrates metal cations followed by UV-visible showed strong selectivity dicalixarenic derived for sodium. The solid liquid extraction of metal picrates followed by 1H-NMR shows an intra- or intermolecular exchange of cations within the calixarene units studied nanocomposites.

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10

Stevens, Geoffrey W., Jilska M. Perera, and Franz Grieser. "Metal ion extraction." Current Opinion in Colloid & Interface Science 2, no. 6 (December 1997): 629–34. http://dx.doi.org/10.1016/s1359-0294(97)80056-8.

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Ma, Yamin, and Andrew W. Rate. "Metals adsorbed to charcoal are not identifiable by sequential extraction." Environmental Chemistry 4, no. 1 (2007): 26. http://dx.doi.org/10.1071/en06051.

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Environmental context. Charcoal is widespread in soils and may be a major component of soil organic matter. Trace metal ions in soils are predominantly associated with solid phase materials, including charcoal, and the identity of the solid phase and the mechanisms of association influence the geochemical behaviour of metals. Metals associated with soil mineral phases are estimated using techniques such as selective sequential extraction, and the sorption reactions of metal ions are well understood. Much less is known about the associations of trace metals with natural charcoal, and metals associated with charcoal in soils are likely to be misidentified in sequential extraction procedures. Abstract. Given that up to 50% of the soil carbon store can consist of charcoal, it is possible that trace elements can become immobilised through their interaction with natural charcoal. Hence, natural charcoal may be a significant sink that has yet to be accounted for in trace element biogeochemical cycles. Testing this hypothesis becomes problematic considering the typically small size (<53 µm) of charcoal particles that occur naturally in Australian soils, making isolation and analysis of natural soil charcoal difficult. Therefore, in this study, we test the robustness of a typical sequential extraction technique by applying it to naturally occurring charcoal that had been spiked with five different concentrations of metal ions (Al3+, Cr3+, Cu2+, Ni2+, Zn2+, Cd2+, Ag+, Pb2+). The method was then applied to contrasting soils mixed with this spiked charcoal. The sequential extraction scheme consisted of the following five extractions the in order: (1) sodium acetate (targeting the adsorbed-exchangeable-carbonate fraction), (2) sodium pyrophosphate (organic fraction), (3) ammonium oxalate (amorphous iron/manganese oxides), (4) hydroxylamine hydrochloride (crystalline iron/manganese oxides) and (5) residual (aqua regia digest). The majority of metals added to the charcoal were extracted in the fractions targeting both the amorphous and crystalline iron and manganese oxides, at low additions of metal ions. At higher additions of metals, the metals were mostly extracted from charcoal in the adsorbed-exchangeable-carbonate fraction. When the spiked charcoal was added to soils, a trend similar to the charcoal-only experiment was observed in the sequential extraction data. Higher concentrations of metals (compared with the control) were extracted for the charcoal-amended soils, in the same fractions as in the charcoal-only extractions. Since the concentration of metals extracted in the various extractants changed with increasing metal loads on charcoal, sequential extractions cannot be used to identify the contribution of metals from the charcoal pool. Therefore, a potentially large pool of trace elements could be misrepresented when sequential extraction techniques are applied, particularly for soils in which there is a large concentration of charcoal. Hence, there is still a large gap in knowledge with regard to the significance of charcoal in ‘real’ soils, particularly with respect to the role of charcoal as a trace element sink.

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Gao, D. L., Ya Fei Guo, Xiao Ping Yu, Shi Qiang Wang, and Tian Long Deng. "Ionic Liquid Extraction Methods for Alkali and Alkaline Earth Metal Ions." Advanced Materials Research 791-793 (September 2013): 224–27. http://dx.doi.org/10.4028/www.scientific.net/amr.791-793.224.

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Ionic liquids (ILs) have been considered as successful alternative extraction solvents, especially, they have become potential replacements of volatile organic compound in the extraction of metal ions for the properties of negligible vapor pressure, nonflammability, high thermostability, etc. In this paper, ILs as environmental friendly solvents in liquid-liquid extractions of alkali and alkaline earth metal ions were summarized, the part of extraction phase compositions, extraction conditions and back extraction method were discussed, and the potency of applications of ILs in extraction and separation of metal ions were also commented.

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Catapang, Allen Vincent, II James Edward Hernandez, Magdaleno R. Vasquez, and Motoi Wada. "Performance of a reactive magnetron sputtering ion source using water vapor plasma." Journal of Physics: Conference Series 2244, no. 1 (April 1, 2022): 012099. http://dx.doi.org/10.1088/1742-6596/2244/1/012099.

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Abstract One of the methods used to produce ions of metals and metal oxides is through extracting them from a magnetron sputter-type ion source. Metal nanoparticles, such as zinc oxide (ZnO), can be deposited using this method. However, low-energy conditions are required to prevent damage to the substrate. The extraction of ions from a differentially pumped, reactive magnetron sputtering source with a pulsed, conduit-type extraction electrode is investigated, with Zn as the metal target and argon and water vapor as discharge support and reactive gases, respectively. The use of water vapor has been shown to improve the properties of ZnO, through hydrogen doping. Using a quadrupole mass analyzer, the species produced from the ion source were detected and identified. Ar, H2O, H3O, and Zn ions were extracted using the pulsed extraction electrode, and the intensity of the extracted ions were found to be frequency dependent. Extraction of ions were observed starting from-40 V extraction potential using a Faraday cup, and the ion beam current appeared to increase in proportion to the extraction voltage. A mechanism for realizing ion extraction using an alternating extraction potential is proposed.

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Muehe, E. Marie, Caroline Schmidt, Jing He, Thomas Helle, and Andreas Kappler. "Microbially Supported Recovery of Precious Metals and Rare Earth Elements from Urban Household Waste Incineration Slag." Advanced Materials Research 1130 (November 2015): 652–55. http://dx.doi.org/10.4028/www.scientific.net/amr.1130.652.

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The use of precious metals and Rare Earth Elements in electronic, medical, and automobile industries is drastically increasing. To meet this demand and to escape the financial pressure of the global metal market, not only mining activities but recently also the recovery of these elements from industrial and urban household waste is in the focus of research. It has been shown that the application of extracting solutions with pH values lower than 4 lead to an economically feasible recovery of industrially precious metals. It is unclear, however, whether and to which extent this abiotic extraction efficiency can potentially be increased by using microorganisms capable of dissolving more stable minerals at low pH. The goal of this project therefore is to first view urban household waste as a resource for metals and evaluate combined abiotic and biotic extraction procedures for an increase in metal extraction efficiency.

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Aide, Michael, Robert Andrews, Robert Curry, Jennifer Kelley, Kyle Koepp, Kenneth New, and Emily Westhoff. "Elemental Release Patterns of Low-level Pb-Zn Dolomitic Tailings in Missouri." Transactions of the Missouri Academy of Science 41, no. 2007 (January 1, 2007): 1–6. http://dx.doi.org/10.30956/0544-540x-41.2007.1.

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Lead and zinc tailings are common in the Ozark region of Missouri and constitute an environmental hazard, particularly to soil and water resources. This study investigated the elemental release patterns of low-level. Pb-Zn dolomitic waste-rock along Bee Fork Creek in Reynolds County, Missouri, to determine whether these tailings are releasing sufficient metal concentrations to adversely impact water and adjacent riparian resources. Aqua-regia digestion of control and impacted sites confirm the presence of substantial concentrations of As, Cd, Pb, Zn and other metals. Hot water and 0.01 M NaNO3 extractions recovered small portions of the total elemental pool and that only a very small portion of the total metal pool is labile. The EDTA extraction recovered greater concentrations of Ca, Mg, Pb, Zn and Cd than the hot water extraction. The Ca and Mg concentrations recovered by the EDTA extraction suggest partial dissolution of the dolomitic waste rock, thus promoting metal release. The EDTA Pb, Zn and Cd concentrations reflect recovery of these metals from the organic, exchangeable and waste rock fractions. Long-term weathering of the dolomite waste rock may promote the continuous, but low level, release of metals to Ozark streams.

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Takeshita, Kenji, and Yutaka Okada. "ICONE15-10756 Counter-current Multistage Extraction of Heavy Metal by Centrifuge Extractor with Taylor-Couette Flow." Proceedings of the International Conference on Nuclear Engineering (ICONE) 2007.15 (2007): _ICONE1510. http://dx.doi.org/10.1299/jsmeicone.2007.15._icone1510_396.

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Zhang, Meng, Ying Lv, Zhanglian Xu, Sheng Wang, and Jie Wang. "The Removal of Platinum Group Metals, Cs, Se, and Te from Nuclear Waste Glass Using Liquid Sb Extraction and Phase Separation Methods." Materials 13, no. 22 (November 23, 2020): 5305. http://dx.doi.org/10.3390/ma13225305.

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Recovery of platinum group metals (PGMs: Pd, Ru, Rh), Cs, Se, and Te from molten borosilicate glass containing simulated high level radwaste through the combination of liquid metal extraction and phase separation method under reductive heat-treatment was studied. In this process, the PGMs were extracted in recovered liquid metal phase, where Sb and Bi metals were used as the collecting metals. Meanwhile, Cs, Se, and Te were enriched in the phase separated potassium-rich materials on glass surface, which were extracted by water. The type of liquid metals had profound influence on the extraction behaviors of PGMs and other fission products from the glass melt. As a result, except the near extraction efficiency of Pd, Sb showed higher affinity for Ru and Rh than Bi metal. The higher phase separation efficiency of potassium-rich materials led to the higher extraction efficiencies of Cs, Se, and Te in liquid Sb extraction than Bi. Among the examined conditions, using liquid Sb extraction, the Pd, Ru, and Rh extraction efficiencies were 78.6%, 62.1% and 100% in liquid Sb metal phase, and 93.76% of Cs, 60.4% of Se, and 23.65% of Te in leachate were obtained.

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Romashev, Artyom, Dongsheng He, Tatiana Aleksandrova, and Nadezhda Nikolaeva. "Technological Typomorphic Associations in Caustobiolites and Methods of Their Extraction." Metals 11, no. 1 (January 9, 2021): 121. http://dx.doi.org/10.3390/met11010121.

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Heavy oil is considered as a multipurpose complex mineral, and the processing of heavy oils as a “complex problem”, aimed both at increasing the yield of light fractions and “transport” ability of oil, and at extracting metals from heavy asphaltene resinous fraction. The recovery of heavy metals (such as vanadium, nickel, titanium, iron, etc.) from heavy oil was performed by cavitation extraction technology with the use of light hydrocarbon solvents and chemical extractants, including a stage of extraction in an ultrasonic field with separation of insoluble fraction of asphaltenes in which a significant part of initial heavy metals and sulfur is concentrated, followed by re-extraction of metals and magnetic separation of metal aggregates.

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Romashev, Artyom, Dongsheng He, Tatiana Aleksandrova, and Nadezhda Nikolaeva. "Technological Typomorphic Associations in Caustobiolites and Methods of Their Extraction." Metals 11, no. 1 (January 9, 2021): 121. http://dx.doi.org/10.3390/met11010121.

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Heavy oil is considered as a multipurpose complex mineral, and the processing of heavy oils as a “complex problem”, aimed both at increasing the yield of light fractions and “transport” ability of oil, and at extracting metals from heavy asphaltene resinous fraction. The recovery of heavy metals (such as vanadium, nickel, titanium, iron, etc.) from heavy oil was performed by cavitation extraction technology with the use of light hydrocarbon solvents and chemical extractants, including a stage of extraction in an ultrasonic field with separation of insoluble fraction of asphaltenes in which a significant part of initial heavy metals and sulfur is concentrated, followed by re-extraction of metals and magnetic separation of metal aggregates.

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Xiang, Xiaoyan, Wentang Xia, and Jianguo Yin. "Resource utilization of titanium-containing slurry by selective extraction and leaching." Metallurgical Research & Technology 115, no. 5 (2018): 504. http://dx.doi.org/10.1051/metal/2018011.

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Resource utilization of titanium-containing slurry was realized by selective extraction and leaching. The results from the experiment confirmed that thistechnology was effective for recycling titanium and niobium from the slurry. During selective extraction, the extract solution with titanium content of 159.40 g/L was obtained after 3 stage-counter current extractions, and the titanium content of extracted residue could be reduced to 1.85 wt% which was much lower than the titanium content of titanium-containing slurry. The results of evaporation experiments indicated that CH2Cl2 in extracted residue could be separated and recovered effectively by evaporation and high temperature is beneficial for the whole process. Meanwhile, the titanium oxide and titanium oxychloride in extracted residue could also be transformed into TiCl4 and recovered by evaporation as the evaporation of dichloromethane in extracted residue. The beneficiation of niobium could be achieved when the evaporated residue was leached with diluted hydrochloric acid, the results of leaching test showed that more than 97% of the aluminum in evaporation residue was dissolved, while, only 1.3% of the niobium was leached. Finally, niobium concentrate with Nb2O5 content of 76.39% was obtained by washing the leaching residue with dilute ammonia water.

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., Lestari. "PENGGUNAAN EKSTRAKSI SEKUENSIAL UNTUK SPESIASI LOGAM BERAT DI SEDIMEN." OSEANA 42, no. 4 (December 30, 2017): 1–12. http://dx.doi.org/10.14203/oseana.2017.vol.42no.4.69.

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THE USE OF SEQUENTIAL EXTRACTION PROCEDURES FOR HEAVY METAL SPECIATION IN SEDIMENT. Metals accumulation in sediments from both natural and anthropogenic sources occurs in the same way, making it difficult to identify and determine the origin of heavy metals present in the sediments. Moreover, the total concentration of metals often does not accurately represent their characteristics and toxicity. In order to overcome the mentioned obstacles, it is necessary to evaluate the environment effect. Single extraction is thus used generally to provide a rapid evaluation of the exchangeable metal fraction in sediments. However, complicated sequential extraction procedures are used to provide more detailed information regarding different metal phase associations.

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Ahmad, Iftikhar, Saeed Ahmad Malik, Shafqat Saeed, Atta-ur Rehman, and Tariq Muhammad Munir. "Phytoremediating a Wastewater-Irrigated Soil Contaminated with Toxic Metals: Comparing the Efficacies of Different Crops." Soil Systems 6, no. 4 (October 10, 2022): 77. http://dx.doi.org/10.3390/soilsystems6040077.

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A formidable challenge in suburban agriculture is the sustainability of soil health following the use of wastewater for irrigation. The wastewater irrigation likely toxifies the crop plants making them unconsumable. We used a multivariate, completely randomized design in a greenhouse, comparing the phytoextraction capacities of Brassica juncea, Eruca sativa, Brassica rapa, and Brassica napus—all grown on silt loam soil irrigated with industrial wastewater, canal water, and a 1:1 mixture, during 2018. The studied Brassica plants were generally closely efficient in remediating toxic metals found in wastewater irrigated soil. Substantial differences between Brassica and Eruca plants/parts were recorded. For example, B. napus had significantly higher metal extraction or accumulation compared to E. sativa for Zn (71%), Cu (69%), Fe (78%), Mn (79%), Cd (101%), Cr (57%), Ni (92%). and Pb (49%). While the water and plant were the main predictors of metal extraction or accumulation, an interaction between the main effects substantially contributed to Cu, Mn, and Fe extractions from soil and accumulations in plants. Significant correlations between biological accumulation coefficient and biological transfer coefficient for many metals further supported the metal extraction or accumulation efficiencies as: B. napus > B. juncea > B. rapa > E. sativa. Root-stem mobility index correlation with stem-leaf mobility index indicated the metal translocation along the root-stem-leaf continuum. Therefore, we suggest that these crops may not be used for human or animal consumption when grown with industrial wastewater of toxic metal concentrations ≥ permissible limits. Rather these plants may serve as effective remediators of toxic metal-polluted soil.

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Hovorukha, V. M., and O. B. Tashyrev. "Thermodynamic prognosis of the efficiency of toxic metals extraction from solution by microorganisms and their genetic potential." Faktori eksperimental'noi evolucii organizmiv 23 (September 9, 2018): 357–62. http://dx.doi.org/10.7124/feeo.v23.1041.

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Aim. Thermodynamic justification of pathways of microbial interaction with metals and development of theoretical foundations of novel biotechnologies for purification of industrial waste water from environmentally hazardous metals-oxidizers (CrО42-, MoО42-, WО42-). Methods. The fields of stability of metal compounds in aqueous solutions in the coordinates of pH-Eh were calculated using classic Pourbaix diagrams. The effectiveness of metals extraction from solutions was evaluated according to Gibbs free energy. Results. On the base of thermodynamic calculations conditions and efficiency of metals extraction by microorganisms was shown. Microbial reduction of CrО42- to insoluble Cr(III) hydroxide was the most effective. Additional carbon and energy sources are required for effective molybdate reduction. Extraction of tungstate can not be carried out by microorganisms. Conclusions. Thermodynamic prognosis is effective method for developing novel environmental biotechnologies for purification of environmentally hazardous metal-containing wastewater and simultaneous treatment of organic waste. Keywords: thermodynamic prognosis, microbial interaction of with metals, metals extraction, purification of metal-containing wastewater, environmental biotechnologies.

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Liu, Wensen, Jian Zhang, Zhenya Xu, Jie Liang, and Zhaowu Zhu. "Study on the Extraction and Separation of Zinc, Cobalt, and Nickel Using Ionquest 801, Cyanex 272, and Their Mixtures." Metals 11, no. 3 (March 1, 2021): 401. http://dx.doi.org/10.3390/met11030401.

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Both Cyanex 272 (bis (2,4,4-trimethylpentyl) phosphinic acid) and Ionquest 801 (2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester) are commonly used for metal extraction and separation, particularly for zinc, cobalt, and nickel, which are often found together in processing solutions. Detailed metal extractions of zinc, cobalt, and nickel were studied in this paper using Cya-nex 272, Ionquest 801, and their mixtures. It was found that they performed very similarly in zinc selectivity over cobalt. Cyanex 272 performed much better than Ionquest 801 in cobalt separation from nickel. However, very good separation of them was also obtained with Ionquest 801 at its low concentration with separation factors over 4000, indicating high metal loading of cobalt can significantly suppress nickel extraction. Slop analysis proved that two moles of dimeric extractants were needed for one mole extraction of zinc and cobalt, but three moles were needed for the extraction of one mole nickel. A synergistic effect was found between Cyanex 272 and Ionquest 801 for three metal extractions with the synergistic species of M(AB) determined by the Job’s method.

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Chang, Yao-Tsung, Zeng-Yei Hseu, and Franz Zehetner. "Evaluation of Phytoavailability of Heavy Metals to Chinese Cabbage (Brassica chinensisL.) in Rural Soils." Scientific World Journal 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/309396.

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This study compared the extractability of Cd, Cu, Ni, Pb, and Zn by 8 extraction protocols for 22 representative rural soils in Taiwan and correlated the extractable amounts of the metals with their uptake by Chinese cabbage for developing an empirical model to predict metal phytoavailability based on soil properties. Chemical agents in these protocols included dilute acids, neutral salts, and chelating agents, in addition to water and the Rhizon soil solution sampler. The highest concentrations of extractable metals were observed in the HCl extraction and the lowest in the Rhizon sampling method. The linear correlation coefficients between extractable metals in soil pools and metals in shoots were higher than those in roots. Correlations between extractable metal concentrations and soil properties were variable; soil pH, clay content, total metal content, and extractable metal concentration were considered together to simulate their combined effects on crop uptake by an empirical model. This combination improved the correlations to different extents for different extraction methods, particularly for Pb, for which the extractable amounts with any extraction protocol did not correlate with crop uptake by simple correlation analysis.

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Ashirov, Makhsud, Ibragimov Rustam Kholikulovich, and Jasur Rakhmatullaev. "Koytash Deposit As A Prospective Object Of Uzbekistan For Expanding Resources Of Wollastonite, Precious Metals And Other Associated Elements." American Journal of Applied sciences 03, no. 01 (January 22, 2021): 25–29. http://dx.doi.org/10.37547/tajas/volume03issue01-06.

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The article discusses complex and conjugated formation of wollostonite, sulfide-rare metal and silver-base polymetallic ores of Koytash deposit. Forms recommended for co-extraction, mineral composition and elements-impurities of them have been revealed. These data on rare-metal sulfide and sulfide-polymetallic ores of Koytash skarn-rare metal deposit proves its prospects in extraction of both rare metal and noble metals, bismuth and wollastonite.

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Yudaev, Pavel A., and Evgeniy M. Chistyakov. "Ionic Liquids as Components of Systems for Metal Extraction." ChemEngineering 6, no. 1 (January 6, 2022): 6. http://dx.doi.org/10.3390/chemengineering6010006.

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This review addresses research and development on the use of ionic liquids as extractants and diluents in the solvent extraction of metals. Primary attention is given to the efficiency and selectivity of metal extraction from industrial wastewater with ionic liquids composed of various cations and anions. The review covers literature sources published in the period of 2010–2021. The bibliography includes 98 references dedicated to research on the extraction and separation of lanthanides (17 sources), actinides (5 sources), heavy metals (35 sources), noble metals, including the platinum group (16 sources), and some other metals.

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Yong, Raymond N., Rosa Galvez-Cloutier, and Yuwaree Phadungchewit. "Selective sequential extraction analysis of heavy-metal retention in soil." Canadian Geotechnical Journal 30, no. 5 (October 1, 1993): 834–47. http://dx.doi.org/10.1139/t93-074.

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The selective sequential extraction method of analysis is used in this study to determine the distribution of heavy metals in some clay soils, to assist in evaluation of the role of the various clay soil solids (clay minerals, organics, amorphous materials, and carbonates) in heavy-metal retention capability as a function of acidity of the leachate. The chemical speciation model MINTEQ (metal speciation equilibrium model for surface and groundwater) is used to calculate the probable percent distribution of different species of heavy metals present in the leachate used. The selective sequential extraction method is based on the fact that different forms of heavy metals that are retained in soil (e.g., as oxides, hydroxides, carbonates, bound with organic matter) can be extracted selectively by using appropriate reagents. The results show that heavy metals can be retained in the four clay soils studied by several soil phases or mechanisms such as exchangeable, carbonate, hydroxide, and organic phases. The retention of heavy metals in any phase depends on soil solution pH, soil constituents, and the type of heavy metal. At high soil solution pH values, retention of heavy metal by precipitation mechanisms prevails, whereas at low soil solution pH, retention by cation exchange mechanisms becomes dominant. The results from the selective sequential extraction analysis support the conclusion of the significance of soil buffer capacity with regard to heavy-metal retention. The capacity of the soils to retain high amounts of heavy metals as they receive increasing amounts of acid (i.e., as the pH is reduced) depends directly on the soil initial pH values and on their buffer capacities. Key words : selective sequential analysis, exchangeable cations, heavy metals, equilibrium models, oxides.

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Aydinalp, C., and A. V. Katkat. "The comparison of extraction methods for evaluating some heavy metals in polluted soils." Plant, Soil and Environment 50, No. 5 (December 10, 2011): 212–17. http://dx.doi.org/10.17221/4024-pse.

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The extractability of Cd, Co, Cr, Ni and Pb was evaluated using ammonium chloride, calcium chloride, strontium chloride and DTPA extractants in this research. The eight surface soils were used to assess plant available metals with different extraction methods. The amounts of metal extracted were related to pseudototal contents, determined after microwave digestion using HNO<sub>3</sub>. Quantification of dissolved metals was used by ICP-MS matrix-matched standards. The obtained results indicated a high variability of metal extraction depending on extraction procedure, source of pollution, and nature of the soil. The results showed that the extractability for calcareous soils was best determined by DTPA. In comparison of chloride salts, a higher efficiency of extraction with ammonium chloride for these soils was found.

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Krylova, L. N. "Efficiency of using ozone for extraction of metals from mineral raw materials." Izvestiya Vuzov. Tsvetnaya Metallurgiya (Universities' Proceedings Non-Ferrous Metallurgy) 28, no. 2 (April 14, 2022): 4–15. http://dx.doi.org/10.17073/0021-3438-2022-2-4-15.

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The paper summarizes the results of studies on the use of ozone for the extraction of non-ferrous, rare and noble metals from ores, beneficiation concentrates and technogenic raw materials identified from world scientific publications and in patent literature since the early 20th century. Ozone is a strong oxidizing agent with an oxidizing potential 1.5 times higher than the potential of chlorine in an acidic environment. Even refractory metals and minerals dissolve with ozone. Metal extraction from mineral raw materials using ozone does not contaminate processed products or generate any hazardous waste. The paper presents a significant number of studies on the use of ozone to dissolve gold and other noble metals in mineral acids showing an increase in the extraction of metals into the solution. The cyanide and thiourea leaching of gold from mineral raw materials with the replacement of oxygen with ozone was investigated. The paper provides the results of the vat and heap leaching of non-ferrous and noble metals using ozone obtained by air or oxygen irradiation with ultraviolet light, in particular with the use of photoelectrochemical treatment. These results were used as a basis for patenting new technologies. The effectiveness of ozone used in the flotation concentration of mineral raw materials, purification and detoxification of solutions and solid products of metallurgical processing, regeneration of other oxidants, metal extraction from process solutions was evaluated. The results of studies on using ozone for the vat leaching of metals from refractory sulfide ores and sulfide beneficiation concentrates in an acid solution, and the study of the ozone-assisted oxidation kinetics of copper, iron, zinc, and molybdenum sulfide minerals are summarized. The paper provides and analyzes the results of using ozone in a combination with other oxidants – hydrogen peroxide and iron (III) ions – for metal extraction from sulfide mineral raw materials in a sulfuric acid. According to the results of most of the studies carried out, it can be concluded that the use of ozone is effective for metal extraction from mineral raw materials as it improves process performance (metal extraction into the solution, selectivity of metal extraction from complex raw materials), and reduces processing time.

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MN, Shruthi, NS Narahari, Bhaskar MG, and Savita C. Teli. "Understanding Material Chemistry of Mobile Handset for Recycling Feasibility Analysis." ECS Transactions 107, no. 1 (April 24, 2022): 6445–53. http://dx.doi.org/10.1149/10701.6445ecst.

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Mobile phones and the smartness associated with them can be attributed to as the single most important factor for such transformation. With volume of mobile handsets sold seeing an increasing trend, emphasis on recycling and waste policy has increased by multifold. Schematic of metal components constituting production of a typical handset and each of the segmented parts has been showcased along with data of waste generation from various states of India. This paper discusses the economic viability of metal extraction considering factors such as metal process time, relative effort and general requirement which identifies high extraction efficiency of metal. Comparison chart has been tabulated for each of the metals with regard to expenditure, revenue generated, processing methods and processing difficulty. The results obtained provide satisfactory evidence to further improve the process to enhance the metal, calculation comparison chart represent each metal expenditure and revenue of Gold and Platinum takes more time for process i.e Au = 24hr, Pt =24hr, Zinc Copper and Aluminum takes minimum time for process Zn=1hr Cu=1hr Al=2hr. Extraction of gold and platinum process are complex compare to other metal highest expenditure cost of metal Au = 1653Rs, Minimum expenditure cost of metal Al = 620Rs Zn =620Rs, Highest revenue from Aluminum = 9000Rs. Minimum Revenue from Silver =1720Rs, Identified high extraction efficiency metals – Cu =99.95%, Al= 99%, Ag =99%. Identified maximum level of purity accepted metals Pt = 99% Au = 99%.

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Andika Putri, Novita Rusmayanti, Yeti Kurniasih, and Ahmadi Ahmadi. "PENGARUH PERBANDINGAN KONSENTRASI TBP : D2EHPA DAN KONSENTRASI PENGEMBAN DALAM FASAORGANIK PADA EKSTRAKSI PERAK DARI LIMBAH FOTO ROENTGEN." Hydrogen: Jurnal Kependidikan Kimia 4, no. 2 (December 17, 2016): 87. http://dx.doi.org/10.33394/hjkk.v4i2.92.

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Photo roentgen used for examination of internal organs can produce wastes that are harmful to health and the environment because they containing silver metal ion(Ag+) inform of silver thiosulfate complex ([Ag(S2O3)2]-3). Therefore it was necessary for the separation of Ag metal so that the metal does not pollute the environment and can be used economically. One way to separate the metal Ag is by solvent extraction techniques. This study aimed to determine the effect of concentration ratio of TBP:D2EHPA and carrier compound concentration in the organic phase of the percent extraction of silver metal then applied to the sample photo roentgen waste. Extraction of the metals Ag done by varying the ratio of the combined carrier concentration of TBP and D2EHPA in kerosene by concentration ratio was 0: 1; 0.25: 0.75; 0.5: 0.5; 0.75: 0.25 and 1: 0 M as well as by varying the carrier concentration in the organic phase ranging from 0 M; 0.5 M; 1 M and 1.5 M. Measuring the concentration of metal ions Ag+in water phase before and after extraction was determined by atomic absorptionspectrophotometer (AAS) at a wavelength of 328,22 nm then calculated percent extraction. Based on the research that obtained the highest percent extraction on single used carrier compounds and compound concentration carrier D2EHPA in optimum water was 0.5 M with 58.22% percent extraction. Applications optimum conditions to the extraction of silver metal obtained from photo roentgenwaste percent extraction was 10.27%.

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Lyatuu, Isaac, Georg Loss, Andrea Farnham, Goodluck W. Lyatuu, Günther Fink, and Mirko S. Winkler. "Associations between Natural Resource Extraction and Incidence of Acute and Chronic Health Conditions: Evidence from Tanzania." International Journal of Environmental Research and Public Health 18, no. 11 (June 4, 2021): 6052. http://dx.doi.org/10.3390/ijerph18116052.

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Natural resource extraction projects are often accompanied by complex environmental and social-ecological changes. In this paper, we evaluated the association between commodity extraction and the incidence of diseases. We retrieved council (district)-level outpatient data from all public and private health facilities from the District Health Information System (DHIS2). We combined this information with population data from the 2012 national population census and a geocoded list of resource extraction projects from the Geological Survey of Tanzania (GST). We used Poisson regression with random effects and cluster-robust standard errors to estimate the district-level associations between the presence of three types of commodity extraction (metals, gemstone, and construction materials) and the total number of patients in each disease category in each year. Metal extraction was associated with reduced incidence of several diseases, including chronic diseases (IRR = 0.61, CI: 0.47–0.80), mental health disorders (IRR = 0.66, CI: 0.47–0.92), and undernutrition (IRR = 0.69, CI: 0.55–0.88). Extraction of construction materials was associated with an increased incidence of chronic diseases (IRR = 1.47, CI: 1.15–1.87). This study found that the presence of natural resources commodity extraction is significantly associated with changes in disease-specific patient volumes reported in Tanzania’s DHIS2. These associations differed substantially between commodities, with the most protective effects shown from metal extraction.

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Fang, Le, Zuotai Zhang, Ying Mei, Linji Xu, and Ze Ren. "Phosphorus Recovery and Simultaneous Heavy Metal Removal from ISSA in a Two-Compartment Cell." Water 15, no. 2 (January 4, 2023): 226. http://dx.doi.org/10.3390/w15020226.

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Traditional acid extraction or electrodialytic remediation (EDR) is inefficient to recover phosphorus (P) from incinerated sewage sludge ash (ISSA). This study used a hybrid process including acid extraction and EDR to extract P from ISSA and remove heavy metals/metals from the P extract sequentially. Specifically, the P extract was obtained by extracting ISSA with 0.2 M H2SO4 and a two-compartment cell was applied in the following EDR process. Constant currents of 15 mA, 35 mA and 50 mA were applied for the electromigration of the heavy metals/metals. Results showed that the efficiency of heavy metals/metals removal fluctuated and was relatively low (approximately 20%) under a current of 15 mA. Increasing the current to 35 mA significantly increased the removal efficiency and that of 50 mA was conspicuous, except Fe, Al and As (<50%). Meanwhile, P gradually immigrated to the catholyte after an EDR duration of 96 h. Consistent with heavy metal/metal immigration results, the pH change and 50 mA voltage drop were dramatic (the pH change was 12 and the voltage drop was 11 V). In addition, flocculent precipitates, which were predominantly Ca, P, Al, Mg and Fe, were found in the catholyte.

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Khan, Z. S., S. M. Shaikh, and A. B. Ade. "Effect of pH on Metal Extraction From Bauxite Ore by Thiobacillus Ferrooxidans." Journal of Scientific Research 2, no. 2 (April 27, 2010): 403–6. http://dx.doi.org/10.3329/jsr.v2i2.4020.

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The extremophile, Thiobacillus ferrooxidans was selected to study the effect of pH on metal extraction from bauxite ore. This bacterium was inoculated in 9K medium having different pH, along with the bauxite ore, as metal source. After one month of incubation the extraction of metals aluminum and iron was measured by spectrophotometric methods. It was found that the extraction of aluminum was found better as compare to iron from bauxite at pH 2. Keywords: Aluminum; iron; metal extraction; pH; Thiobacillus ferrooxidans. © 2010 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. DOI: 10.3329/jsr.v2i2.4020 J. Sci. Res. 2 (2), 403-406 (2010)

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Ohto, Keisuke, Shinpei Nakashima, Yudai Tanaka, Shintaro Morisada, Hidetaka Kawakita, and Tatsuya Oshima. "Extraction Behavior of Trivalent Rare Earth Metal Ions with Diphosphonic Acid Type Extraction Reagent." Key Engineering Materials 884 (May 2021): 133–39. http://dx.doi.org/10.4028/www.scientific.net/kem.884.133.

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Bis(phenyl hydrogen phosphonato)-1-hydroxy-3,5,5-trimethylheptane has been prepared to investigate extraction behavior of a series of trivalent rare earth metal ions. This diphosphonic acid extraction reagent exhibited high extraction ability to all ions examined, especially Sc ion. It did not exhibit apparent dependency in acid concentration, which corresponds to ion-exchange mechanism, probably due to extremely high extraction ability. Although the mutual separation of rare earths was difficult with this reagent, group separation of rare earths over divalent base metals can be accomplished. Compared with the extraction of base metals, it was found that this reagent with branched alkyl chain exhibited lower in extraction ability than diphosphonic acid with linear chain, bis(phenyl hydrogen phosphonato)-1-hydroxy-hexadecane.

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Fedorov, A. Y., and A. V. Levina. "The possibility of using DES based on polypropylene glycol 425 and tetrabuthylammonium bromide in the extraction processes of transition metals." IOP Conference Series: Materials Science and Engineering 1212, no. 1 (January 1, 2022): 012024. http://dx.doi.org/10.1088/1757-899x/1212/1/012024.

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Abstract Traditionally, the method of liquid extraction is used to extract metals from aqueous. This work is devoted to the combination of perspective alternative for hazardous solvents (aqueous two-phase systems based on water-soluble polymers) and the novel deep eutectic solvents in the non-ferrous metals extraction processes. In this work, the synthesis of deep eutectic solvent based on a water-soluble polymer (PPG-425) and tetrabutylammonium bromide (TBAB) by stirring for 10 minutes at 80° C has been shown. The obtained results showed not only the possibility of using DES in the metal extraction process, but the selectivity to the Fe(III) and Zn(III), the distribution coefficients were 71.64 and 25.17 respectively. The metal concentrations were determined spectrophotometrically using 4-(2-pyridylazo)resorcinol. This work shows the perspectives of using DESs in the metal extraction processes.

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Snyman, H. G. "Characterisation of sewage sludge metals for classification purposes using the potentially leachable metal fraction." Water Science and Technology 44, no. 10 (November 1, 2001): 107–14. http://dx.doi.org/10.2166/wst.2001.0594.

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The South African sludge guidelines were revised in 1997 with considerable amendments to the heavy metal loading and usage restrictions. The industry continued using the aqua regia extraction method to characterise and classify sewage sludge. This meant that a Class D sludge (most stable class and sellable product) could not be generated at any South African plant. This caused the industry to seek alternative non-beneficial disposal methods. It was then realised that the metal limits were in fact the TCLP (Toxicity Characteristic Leaching Procedure) extractable limit. This method was developed to determine the potential of a waste to contaminate ground and/or surface water. The agriculturists, however, use the NH4EDTA extractable fraction to establish metal concentration in soils. This paper specifically aims to establish the feasibility of using the available metals extraction methods such as NH4EDTA and TCLP to determine the fate and therefore the risk of sludge-borne metals (Cd, Pb, Zn, Cu). The results show that the TCLP extraction method could potentially underestimate the impact of sewage sludge-borne metals when amended to agricultural soils. The extraction efficiency of the NH4EDTA and TCLP methods relative to the aqua regia extraction method was presented for Cd, Pb, Zn and Cu. The NH4EDTA extraction method seems to be an alternative to the aqua regia method, especially since the NH4EDTA measures the fraction of the metal that may become available in the environment. It is recommended that the aqua regia and NH4EDTA be used to classify and characterise the metal content of South African sludges.

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Yudaev, Pavel, and Evgeniy Chistyakov. "Chelating Extractants for Metals." Metals 12, no. 8 (July 28, 2022): 1275. http://dx.doi.org/10.3390/met12081275.

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In the present review, works on the classes of chelating extractants for metals, compounds with several amide and carboxyl groups, azomethines, oximes, macrocyclic compounds (crown ethers and calixarenes), phenanthroline derivatives, and others are systematized. This review focuses on the efficiency and selectivity of the extractants in the recovery of metals from industrial wastewater, soil, spent raw materials, and the separation of metal mixtures. As a result of this study, it was found that over the past seven years, the largest number of works has been devoted to the extraction of heavy metals with amino acids (16 articles), azomethines and oximes (12 articles), lanthanids with amide compounds (15 articles), lanthanides and actinides with phenanthroline derivatives (7 articles), and noble metals with calixarenes (4 articles). Analysis of the literature showed that amino acids are especially effective for extracting heavy metals from the soil; thiodiglycolamides and aminocalixarenes for extracting noble metals from industrial waste; amide compounds, azomethines, oximes, and phenanthroline derivatives for extracting actinides; amide compounds for extracting lanthanides; crown ethers for extracting radioactive strontium, rhenium and technetium. The most studied parameters of extraction processes in the reviewed articles were the distribution ratios and separation factors. Based on the reviewed articles, it follows that chelate polydentate compounds are more efficient compounds for the extraction of metals from secondary resources compared to monodentate compounds.

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Campillo-Cora, Claudia, Laura Rodríguez-González, Manuel Arias-Estévez, David Fernández-Calviño, and Diego Soto-Gómez. "Influence of Soil Properties and Initial Concentration on the Fractionation of Nickel, Zinc, Copper and Lead in Soils Derived from Different Parent Materials." Agronomy 11, no. 2 (February 9, 2021): 301. http://dx.doi.org/10.3390/agronomy11020301.

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Different fractions of Ni, Zn, Cu and Pb were determined in metal-spiked forest soils derived from four parent materials using three extractants (H2O, CaCl2 and diethylenetriaminepentaacetic acid (DTPA)). It is important to determine how parent materials and soil properties affect the retention of these metals in order to predict their behavior and act accordingly in the event of accidental spillage, for example. The extraction of fractions was not sequential (before carrying out the extractions, the soil samples were divided into three parts), so the CaCl2 fraction also included the H2O one, and the DTPA fraction contained the other two. With the results, we developed models to predict the extraction of each fraction employing the physicochemical characteristics of the soil (e.g., pH, organic matter content and texture values) and the amount of metal added. The objective of this work was to determine how the properties of the soil would influence the fractioning of the metals considered, and through these characteristics create models to predict the behavior of each metal fraction. We found correlations between the different fractions of Ni and Zn, suggesting that there are soil properties that condition the retention of both metals. Pb and Cu showed different behavior than Zn or Ni, since the proportions extracted by H2O and CaCl2 were much lower. Regarding the DTPA fraction, unlike the case of Ni or Zn, the extraction of Cu and Pb was more homogeneous; they did not show great variation in different soils, even when considering the results of extraction in limestone soils. This may be due to the fact that the soil properties do not exert an important effect on their availability, or these two metals are considerably sensitive to the effect of pH, and no differences were observed because the extraction of the DTPA fraction was conducted with a buffered solution. For each fraction of metal used, we obtained a model with R2 always greater than 0.65. Considering these results, we can conclude that it is possible to predict Zn, Ni, Cu and Pb availability in soils developed on different parent materials. This can be achieved by identifying some basic soil characteristics and applying the developed equations.

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Wojtkowska, Małgorzata, and Jan Bogacki. "Assessment of Trace Metals Contamination, Species Distribution and Mobility in River Sediments Using EDTA Extraction." International Journal of Environmental Research and Public Health 19, no. 12 (June 7, 2022): 6978. http://dx.doi.org/10.3390/ijerph19126978.

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The impact of the ethylenediaminetetraacetic acid (EDTA) on speciation image of selected trace metals (Zn, Cd, Cu, Pb) in bottom sediments was determined. The influence on the effectiveness of metal removal of extraction multiplicity, type of metal, extraction time and concentration of EDTA were analyzed. With the increase of extraction multiplicity, the concentration of EDTA and contact time, the efficiency of trace metals leaching increased. The speciation analysis revealed that EDTA not only leached metals from bioavailable fractions, but also caused the transition of the metals between the fractions. The biggest amounts of bioavailable forms were found for Cd, less for Zn. The amount of bioavailable fraction was the lowest for Cu and Pb. The two first-order kinetic models fitted well the kinetics of metals extraction with EDTA, allowing the metals fractionation into “labile” (Q1), “moderately labile” (Q2) and “not extractable” fractions (Q3).

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Jena, P. K., and E. A. Brocchi. "Metal Extraction Through Chlorine Metallurgy." Mineral Processing and Extractive Metallurgy Review 16, no. 4 (1996): 211–37. http://dx.doi.org/10.1080/08827509608914136.

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JENA, P. K., and E. A. BROCCHI. "Metal Extraction Through Chlorine Metallurgy." Mineral Processing and Extractive Metallurgy Review 16, no. 4 (January 1997): 211–37. http://dx.doi.org/10.1080/08827509708914136.

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Yang, Sixie, Fan Zhang, Huaiping Ding, Ping He, and Haoshen Zhou. "Lithium Metal Extraction from Seawater." Joule 2, no. 9 (September 2018): 1648–51. http://dx.doi.org/10.1016/j.joule.2018.07.006.

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45

de Leon, Aned, and Abraham F. Jalbout. "Metal induced molecular nano-extraction." Theoretical Chemistry Accounts 121, no. 5-6 (September 18, 2008): 247–55. http://dx.doi.org/10.1007/s00214-008-0470-3.

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Dumazet-Bonnamour, Isabelle, Hatem Halouani, Farhana Oueslati, and Roger Lamartine. "Calixarenes for metal cations extraction." Comptes Rendus Chimie 8, no. 5 (May 2005): 881–91. http://dx.doi.org/10.1016/j.crci.2005.02.004.

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Artem'ev, O. I. "Metal extraction in activation analysis." Journal of Radioanalytical and Nuclear Chemistry Articles 173, no. 1 (September 1993): 125–35. http://dx.doi.org/10.1007/bf02102704.

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Chen, Ting-Chien, Edward Macauley, and Andrew Hong. "Selection and test of effective chelators for removal of heavy metals from contaminated soils." Canadian Journal of Civil Engineering 22, no. 6 (December 1, 1995): 1185–97. http://dx.doi.org/10.1139/l95-137.

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Heavy metal contamination of soil is a common problem at many hazardous waste sites. Chelating extraction of heavy metals has been proposed as a remediation technique for contaminated soils. A useful method was developed, which assessed 190 ligands for their ability in extraction and recovery of target metals, including cadmium, copper, lead, mercury, nickel, and zinc. Chelator performance was evaluated based on equilibrium calculations with an emphasis on the potential of recovering both the metals and chelating agents. Batch equilibration experiments over 24-h periods were performed to test three chelating agents, S-carboxymethyl-cysteine (SCMC), N-2-acetamidoiminodiacetic acid (ADA), and pyridine-2,6-dicarboxylic acid (PDA), which were deemed suitable for the extraction of cadmium, copper, lead, and zinc from soil. All three chelators demonstrated high extraction capability toward their respective target metals across a wide range of pH, metal, and ligand concentrations. In addition, all three chelators exhibited good recovery potential at moderately elevated pH values. The potential of many chelating agents and their effective pH ranges in the remediation of soils contaminated with heavy metals are reported. Key words: heavy metal, soil, contamination, chelation, remediation.

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Yabalak, Erdal, and Murat Gizir. "Subcritical and supercritical fluid extraction of heavy metals from sand and sewage sludge." Journal of the Serbian Chemical Society 78, no. 7 (2013): 1013–22. http://dx.doi.org/10.2298/jsc120321123y.

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Demetalization of Pb, Ni, Zn, Cu and Cr heavy metal ions from sea sand and real samples of sewage sludge by subcritical water and supercritical carbon dioxide was investigated. Experimental parameters such as temperature, pressure, extraction time in the static and dynamic mode and sampling were optimized in order to determine the suitable conditions for high metals removal. The best extraction efficiencies were obtained by using acetyl acetonate as chelating agent in both subcritical water and supercritical CO2 extractions for real and artificial samples. Samples collected from extraction system using both subcritical water and supercritical carbon dioxide were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The highest recoveries (%) obtained from real samples for Cr, Cu, Ni, Pb and Zn were 77.25, 95.1, 84.82, 94.92 and 98.39, respectively, with the chelating agent in the subcritical water extraction.

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Huntington, Victoria E., Frédéric Coulon, and Stuart T. Wagland. "Innovative Resource Recovery from Industrial Sites: A Critical Review." Sustainability 15, no. 1 (December 28, 2022): 489. http://dx.doi.org/10.3390/su15010489.

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Global net-zero pledges are instigating a societal shift from a fossil-fuel-based economy to renewables. This change facilitates the use of batteries, solar photovoltaic (PV), wind turbines, etc., all of which are underpinned by critical metals. Raw metal extraction is not renewable and environmental pledges made by the government will not be met if this continues. Historic industrial sites contain vast waste stocks. These sites already have an established infrastructure for resource extraction. Applying green solvents and deep eutectic solvents (DES) to such sites for resource recovery alleviates pressure on existing raw extraction processes whilst generating more immediate stores of critical metal along with relatively insignificant environmental impacts. Existing remediation/recovery options have varying metal recovery efficiencies usually combined with high operating costs. Using novel green solvents, such as DES, on historic sites provides an opportunity to recover metals from waste that ordinarily would be looked over. Increased extraction of critical metals from waste material within the UK will reduce reliance on imported metals and improve critical metals security of supply to UK markets and the wider economy The use of these solvents provides an environmentally friendly alternative but also regenerates the legacy of waste from historic industrial sites and consequently implements a circular economy. Adopting the use of green solvents will meet EU environmental pledges, and boost the economy, by recovering metals from legacy sites to meet exponentially growing metal demand.

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Journal articles on the topic 'Metal Extraction'

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