Relevant bibliographies by topics / Leaching agent

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  2. Dissertations / Theses
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Academic literature on the topic 'Leaching agent'

Author: Grafiati
Published: 4 June 2021
Last updated: 7 February 2022

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Journal articles on the topic "Leaching agent"

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Zhang, Gui Fang, Peng Yan, and Qing Rong Yang. "Experimental Study on Concentrating Scandium by Leaching from Associated Scandium Ore." Advanced Materials Research 734-737 (August 2013): 1033–36. http://dx.doi.org/10.4028/www.scientific.net/amr.734-737.1033.

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Based on the benefication of the complex silicate ore containing scandium, the research about aid-leaching agent used in the leaching of the scandium concentrate was been conducted. And the suitable leaching agent and aid-leaching agent which the useful ions entered into leaching liquid and the harmful ions were kept in leaching residue were been found according to the experiment results. For the scandium of sample existed various complex silicate ore as isomorphism form, the research has adopted hydrochloric acid with aid-leaching agent to dissociate the silicate ore and make scandium entering into solution. The research results has shown that the scandium leaching rate could reach 92.06% under the optimal conditions which the hydrochloric acid concentration is 22.8%, the dosage of aid leaching agent is 6%, liquid solid ratio is 4:1, particle size of leaching material totally is less than 0.15mm and leaching time is 8h.
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Chen, Yuqian, Junwen Zhou, Libo Zhang, et al. "Microwave-assisted and regular leaching of germanium from the germanium-rich lignite ash." Green Processing and Synthesis 7, no. 6 (2018): 538–45. http://dx.doi.org/10.1515/gps-2017-0137.

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Abstract Demand for germanium (Ge) is rapidly growing in recent years in various fields including semiconductors, aerospace, and solar cells. However, the Ge resources are very limited in the world. Hence, in this work, microwave-assisted leaching and conventional leaching methods are employed for the leaching of Ge from the Ge-rich lignite ash (GA). The effects of leaching temperature, leaching time, initial acid concentration, oxidizing agent amount, and stirring speed on leaching of Ge were investigated and microwave-assisted and conventional methods of leaching were compared. Here, HCl solution is used as a leaching agent, and MnO2 is used as an oxidizing agent. From the results, the leaching rate of Ge was found to be 89.49% in the microwave-assisted method, and 83.62% in the conventional leaching method. The optimal conditions for microwave-assisted method include a leaching temperature of 65°C, a leaching time of 90 min, an oxidizing agent amount of 10 g/l, an initial acid concentration of 10 mol/l, and a stirring speed of 250 rpm. The leaching rate of Ge significantly improved in the microwave-assisted method as compared to the conventional method. Therefore, the microwave-assisted method is a suitable method for the leaching of Ge from the GA and is a novel way for the efficient utilization of Ge concentrate.
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da Silva, Wagner Claudio, and F. R. Valenzuela-Díaz. "Nanomaterial as Microbial Agent to Paints." Materials Science Forum 727-728 (August 2012): 1751–56. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.1751.

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Quaternary ammonium compounds are widely used as antiseptic agents, disinfectants, detergents and preservatives. In addition, quaternary ammonium compounds are often used as algaecides, and chloride dodecyl dimethyl benzyl ammonium chloride (benzalkonium chloride) is the most effective against these microorganisms. However benzalkonium chloride is not used as surface algaecide compound due its high hydrophobicity, bring on high leaching of this compound when the surface is exposed to high humidity. Currently, compounds such as diuron and s-triazine are used as algaecides, but had been detected in coastal regions in high levels concentration showing the leaching of these biocides. Then raise the necessity to develop a new algaecide to overcome the failings of leaching of the compounds used nowadays. Nanomaterial as organoclay is an excellent alternative because they have highly hydrophobic. Therefore in this work was synthesized a new nanomaterial using benzalkonium chloride, which was applied in a house paint formulation. The nanomaterial was characterized by the techniques of X-ray diffraction and thermo gravimetric analysis. The biocide capability as well as resistance to weathering of the nanomaterial was checked thought microbiological and leaching test. The new nanomaterial synthesized in this study had a high potential to be used as a microbial agent in paints.
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Wu, Dan Dan, Shu Ming Wen, Jing Yang, Yi Jie Wang, and Chao Lv. "A Study on Leaching of Zinc Oxide Ore in Ammonium Sulfate Solution." Applied Mechanics and Materials 522-524 (February 2014): 1463–66. http://dx.doi.org/10.4028/www.scientific.net/amm.522-524.1463.

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In this paper, the leaching effect of zinc oxide ore was investigated using ammonium sulfate solution as leaching agent. The effects of temperature, concentration of ammonium sulfate, average particle size and stirring speed on the leaching of zinc oxide ore were studied. The leaching rate increased with increasing solution temperature, concentration, and stirring speed as well as with decreasing average particle size. Ammonium sulfate solution can therefore be used as an effective leaching agent for zinc extraction from zinc oxide ore.
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Dong, Hua Sheng, and Jing Yang. "The Leaching of Copper Oxide Ore in Ammonium Chloride Solution." Applied Mechanics and Materials 675-677 (October 2014): 1459–62. http://dx.doi.org/10.4028/www.scientific.net/amm.675-677.1459.

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In this study, the leaching effect of copper oxide ore was investigated using ammonium chloride solution as leaching agent. The effects of temperature, concentration of ammonium chloride, average particle size and stirring speed on the leaching of copper oxide ore were investigated. The leaching rate increased with increasing solution temperature, concentration, and stirring speed as well as with decreasing average particle size. Ammonium chloride solution can therefore be used as an effective leaching agent for copper extraction from copper oxide ore.
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Yang, Jin Lin, Shao Jian Ma, Wei Mo, Jin Peng Feng, Xiu Juan Su, and Gui Fang Wang. "Study on Recovering Zinc from Gossan." Advanced Materials Research 454 (January 2012): 329–32. http://dx.doi.org/10.4028/www.scientific.net/amr.454.329.

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In this paper, the conventional physical separation method such as flotation, gravity separation, magnetic separation, alkaline leaching and sulfuric acid leaching were studied. The effects of grinding fineness, amount of agent, magnetic intensity, roasting temperature, roasting time, the leaching agent and leaching time on the leaching of zinc were investigated, respectively. The results show that the leaching rate of zinc is below 50% in the conventional alkaline leaching, and the leaching rate of zinc is below 85% and the leaching rate of iron is above 35% in sulfuric acid leaching. Compared with XRD pattern of the raw ore, the different diffraction peaks of smithsonite is off in alkaline leaching products. In sulfuric acid leaching, the different diffraction peaks of smithsonite are off in the leaching products when sulfuric acid concentration is less than 60 g/L. After 60 g/L, the different diffraction peaks of smithsonite and siderite are off in the leaching products.
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He, Wei, Guo Hua Ye, and Xiong Tong. "Study on Direct Acid Leaching Vanadium without Grinding and Roasting from Clay Vanadium Ore in Hunan." Applied Mechanics and Materials 316-317 (April 2013): 882–86. http://dx.doi.org/10.4028/www.scientific.net/amm.316-317.882.

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Abstract：A new technology of direct acid leaching vanadium without grinding and roasting was put forward, and the effects of leaching factors including dosage of sulfuric acid, type and dosage of assistant leaching agent, leaching time and temperature, liquid-solid ratio on the vanadium leaching rate were systematically investigated. The results show that vanadium leaching rate could be up to 92.58% under the optimal conditions of sulfuric acid dosage of 30%, MnO2 as assistant leaching agent and its dosage of 1.5%, leaching time of 6h, leaching temperature of 90°C, liquid-solid ratio of 1:1, and the leaching performance is perfect. Due to leaving out the high costing grinding system and the complex roasting system, the new technology has advantages in shortening the process, decreasing the cost, avoiding pollution generated by roasting comparing with the traditional technologies, and it can meet the requirement of modern metallurgy very well.
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Jiang, Chen Guang, and Qing Jie Tang. "Study on Extracting Technology of Vc from Momordica charantia." Advanced Materials Research 781-784 (September 2013): 606–9. http://dx.doi.org/10.4028/www.scientific.net/amr.781-784.606.

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Balsam pear was used as the research object in experiment, the technological parameters were studied such as the way of crushing, leaching agent type and its concentration, solid-liquid ratio, ultrasonic extraction temperature, time, power's influence on the extraction yield of Vc, and the ultrasonic extraction time, temperature, ultrasonic power on the L9 (34) orthogonal test analysis. Results showed that bitter melon slices, and solid-liquid ratio is 1:7, citric acid as leaching agent and the concentration of 1%, ultrasonic power is 80 w, leaching temperature 30 °C, 40 min leaching time, leaching of balsam pear Vc the highest rate.
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Lie, Jenni, Stefani Tanda, and Jhy-Chern Liu. "Subcritical Water Extraction of Valuable Metals from Spent Lithium-Ion Batteries." Molecules 25, no. 9 (2020): 2166. http://dx.doi.org/10.3390/molecules25092166.

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The leaching of valuable metals (Co, Li, and Mn) from spent lithium-ion batteries (LIBs) was studied using subcritical water extraction (SWE). Two types of leaching agents, hydrochloric acid (HCl) and ascorbic acid, were used, and the effects of acid concentration and temperature were investigated. Leaching efficiency of metals increased with increasing acid concentration and temperature. Ascorbic acid performed better than HCl, which was attributed to ascorbic acid’s dual functions as an acidic leaching agent and a reducing agent that facilitates leaching reactions, while HCl mainly provides acidity. The chemical analysis of leaching residue by X-ray photoelectron spectroscopy (XPS) revealed that Co(III) oxide could be totally leached out in ascorbic acid but not in HCl. More than 95% of Co, Li, and Mn were leached out from spent LIBs’ cathode powder by SWE using 0.2 M of ascorbic acid within 30 min at 100 °C, initial pressure of 10 bar, and solid-to-liquid ratio of 10 g/L. The application of SWE with a mild concentration of ascorbic acid at 100 °C could be an alternative process for the recovery of valuable metal in spent LIBs. The process has the advantages of rapid reaction rate and energy efficiency that may benefit development of a circular economy.
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Zhu, Wei-Jun, Guo-Qiang Tian, Yang Lu, Kai Miao, and Di-Chen Li. "Leaching improvement of ceramic cores for hollow turbine blades based on additive manufacturing." Advances in Manufacturing 7, no. 4 (2019): 353–63. http://dx.doi.org/10.1007/s40436-019-00273-2.

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Abstract The precision casting method based on alumina-based ceramic cores is one of the main techniques used to manufacture hollow turbine blades. Additive manufacturing (AM) technology provides an alternate solution to fabricating ceramic cores quickly and precisely. As the complexity of the structure increases and the strength of the material improves, the leaching process of the cores becomes more complicated. This study proposes a compound pore-forming method to increase the porosity of ceramic cores by adding a preformed-pore agent and materials that convert to easy-to-corrode phases. The preformed-pore agents (e.g., carbon fibers) can be burned off during sintering to form pores before the leaching, and the easy-to-corrode phases (e.g., CaCO3, SiO2, β-Al2O3) can be leached firstly to form pores during the leaching process. The pores formed in the aforementioned two stages increase the contact area of the cores and leaching solution, thus improving the leaching rate. In the current study, the additive amount of the preformed-pore agent was optimized, and the effect of the easy-to-corrode phases on the comprehensive properties of the cores was then compared. Based on this, the corresponding model was established.
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Dissertations / Theses on the topic "Leaching agent"

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MOTNY, RIYADH M. "COMPOSITIONAL ANALYSIS OF CERIUM AND CESIUM IN RAPID SETTING CEMENT AS AN IMMOBILIZATION AGENT FOR NUCLEAR WASTE." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/5749.

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A feasibility of rapid setting cement (RSC) as an agent of immobilization for certain elements such as fission products or radioactive materials was explored. Cerium (Ce) and cesium (Cs) have been selected as a surrogate for U and/or Pu and fission products, respectively, in this study in three phases. In Phase I, RSC was evaluated for physical properties (e.g., porosity, density, pH values, etc.) using two groups methods—the cement powder at different concentrations of Ce (2 – 10 wt%) with deionized water (DIW) and artificial seawater (ASW). The results showed that the final setting time and compressive strength of RSC in DIW and ASW solutions decreased as Ce content increased. The X-ray diffraction patterns revealed two newly identified phases, namely CeAl11O18 and Ce4.667 (SiO4)3O. The morphology of matrix samples showed that the existence of Ce distributed on the pore wall or clustered with Si, Al, Mg, K, P, Fe, and O. In Phase II, laser-induced breakdown spectroscopy (LIBS) technique together with univariate and multivariate analyses of the principal component analysis (PCA) and partial least squares (PLS) were applied to detect the surrogate elements (Ce (0.5 – 8 wt%) and Cs (0.5 – 4 wt%)) for nuclear materials captured in ceramic materials. The best calibration curves for Ce and Cs in samples were created using the peak areas of the Ce 571.8 nm line and Cs 697.1 nm line, respectively. PCA method was applied to explain 85.5 % for Ce-cement samples in DIW and 91.4 % for those in ASW. Samples with Cs indicated similar PCA trends. The PLS calibration curves for Ce and Cs samples in DIW and those in ASW were made using seven and eight latent variables (LV). In Phase III, the leaching behaviors of Ce and Cs mixture with DIW and ASW under both dynamic and static leach conditions were investigated according to the ANSI/ANS 16.1-2003 standard method. Elemental compositions were analyzed using an inductively coupled plasma-mass spectrometry (ICP-MS) for the leaching periods of 2, 7, and 24 hours and 2, 3, 4, 5, 14, 28, 43, and 90 days. Three mathematical models—first-order reaction model (FRM), diffusion model (DM), and first-order reaction/diffusion model (FRDM)—were fitted to assess the leaching parameters of immobilized radionuclides in the RSC matrix. Results showed that leaching of 140Ce and 133Cs from RSC matrices with (DIW and ASW) under both dynamic and static leach conditions was less than 20%. It was found that the leaching phenomena of 140Ce and 133Cs was dominantly controlled by FRM with a weak effect of DM, which was best fitted by FRDM. Here, the average leachability index (L) for 140Ce and 133Cs, are greater than the recommended minimum of 6 that allowed their acceptance for disposal. These studies indicated a good feasibility of using RSC with DIW and ASW for immobilizing non-radioactive Ce and Cs and RSC had a potential for applying to actual radioactive materials.
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Tong, Libin. "Sulfur dispersing agents for nickel sulfide leaching above the melting point of sulfur." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/3427.

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The effects of sulfur dispersing agents (SDAs) in the oxygen pressure leaching of nickel concentrate at medium temperature were investigated. Liquid sulfur-aqueous solution interfacial tensions and liquid sulfur-sulfide mineral contact angles were measured at 140ºC, 690 kPa overpressure by nitrogen, and 1.0 mol/L NiSO₄. The effects of SDAs including lignosulfonate, Quebracho, o-phenylenediamine (OPD), and humic acid were evaluated by the calculation of the work of adhesion in the liquid sulfur-sulfide mineral-aqueous solution systems. It was found that the sulfide mineral surface is sulfophobic at pH from 4.1 to 4.5 due to the hydrolysis of nickel (II) ions to nickel hydroxide and the deposition of nickel hydroxide on the mineral surface. These findings apply to four different sulfide mineral systems, including pentlandite, nickeliferous pyrrhotite, pyrrhotite, and chalcopyrite. Lignosulfonate, Quebracho, and humic acid were found to significantly reduce the work of adhesion indicating they should be effective SDAs. OPD is ineffective in changing the work of adhesion of sulfur on the mineral sulfides indicating that it is not a good candidate for sulfur dispersion. The adsorption behavior of SDAs, including lignosulfonate, Quebracho, OPD, and humic acid on elemental sulfur and on nickel sulfide concentrate was investigated. Lignosulfonate, Quebracho, and humic acid were characterized by their infrared spectra. The charge changes on elemental sulfur surface were characterized by the measurement of the electrokinetic sonic amplitude (ESA) in the absence or presence of SDAs. The adsorption of lignosulfonate on molten sulfur surface was calculated by the Gibbs Equation. The adsorption of lignosulfonate, Quebracho, and humic acid on the nickel concentrate was investigated at ambient temperature. The adsorption of lignosulfonate, Quebracho, and humic acid on the nickel concentrate was found to be monolayer adsorption, which was fitted to the Langmuir adsorption isotherm. Electrostatic interaction and ion-binding are the possible mechanisms for the adsorption of lignosulfonate and humic acid on the nickel concentrate. Quebracho is adsorbed on the nickel concentrate through hydroxyl and sulfonate groups. OPD cannot adsorb on the molten sulfur surface. OPD undergoes chemical change in aqueous solution in the presence of ferric at ambient temperature. Oxygen pressure leaching experiments were performed at 140 or 150ºC under 690 kPa oxygen overpressure. The particle size of the nickel concentrate was found to be an important factor in leaching. During the leaching of nickel concentrate with P₈₀ of 48 µm, the SDAs were believed to be fully degraded before nickel was fully extracted. At most 66% nickel was extracted in the presence of 20 kg/t OPD. Fine grinding (P₈₀ of 10 µm) was sufficient for 99% nickel recovery at low pulp density while at high pulp density, the nickel extraction increased from 95% to 99% with addition of SDAs. Based on the leaching results on a nickel concentrate sample (-44 µm), OPD had the effect of increasing the nickel extraction to about 99%, followed by Quebracho (83%), lignosulfonate (72%), and humic acid (61%). It is suggested that the oxidation product of OPD is effective in solving the sulfur wetting problem in leaching. 97% nickel was recovered in the presence of 5 g/L chloride ion. Chloride ion has an effect to enhance the performance of lignosulfonate under leaching conditions.
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Silva, Wagner Claudio da. "Argila organofílica como agente microbiano para tintas." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-04072012-171310/.

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Sais quaternários de amônio são amplamente usados como agentes antissépticos, desinfetantes, detergentes e preservantes. Além disso, sais quaternários de amônio são frequentemente utilizados como algicidas, sendo o cloreto de dodecil dimetil benzil amônio (Cloreto de benzalcônio) o mais efetivo contra estes microorganismos. No entanto sua aplicação como algicida de superfícies é limitada, devido a sua alta hidrofilicidade, ocasionando uma alta lixiviação deste composto quando a superfície é exposta à alta umidade e intempéries de clima tropical. Atualmente compostos como Diuron e S-Triazina são empregados como algicidas, considerados de baixa lixiviação. No entanto, altos níveis de concentração destes biocidas foram detectados em regiões costeiras evidenciando a lixiviação destes biocidas, quando utilizados em tintas para casco de navio. Assim surge a necessidade do desenvolvimento de um algicida para suprir as deficiências de lixiviação dos compostos empregados atualmente. Materiais como as argilas organofílicas são uma excelente alternativa, pois são altamente hidrofóbicas. Portanto sintetizou-se neste trabalho uma argila organofílica utilizando-se cloreto de benzalcônio, a qual foi utilizada em uma formulação de tinta imobiliária. O material foi caracterizado pelas técnicas de difração de Raios X e análise termogravimétrica. Um filme de tinta foi submetido a uma câmara de lixiviação, simulando a ação da chuva. Após a lixiviação o filme de tinta seguiu para testes microbiológicos, para verificar se a superfície ainda possui proteção microbiana. As algas testadas foram das espécies Phormidium cebenense, Trentepohlia odorata, Chlorella sp e Scenedesmus quadricauda colocadas num pool de algas. Através das análises de Difração de Raios X e termogravimétrica é possível determinar a estrutura e quantificar o teor cloreto de benzalcônio no material, respectivamente. Os testes microbiológicos e de lixiviação avaliaram a capacidade biocida assim como a resistência à intempérie do material. O novo composto sintetizado neste trabalho apresentou um alto potencial para uso como agente microbiano em tintas.<br>Quaternary ammonium compounds are widely used as antiseptic agents, disinfectants, detergents and preservatives. In addition, quaternary ammonium compounds are often used as algaecides, and dodecyl dimethyl benzyl ammonium chloride (benzalkonium chloride) is the most effective against these microorganisms. However benzalkonium chloride is not used as surface algaecide compound due its high hydrophilic, bring on high leaching of this compound when the surface is exposed to high humidity and severe weather from tropical climate. Currently, compounds such as diuron and s-triazine are used as microbial agent, considered low leaching. However diuron and s-triazine were detected in coastal regions in high levels concentration showing the leaching of these biocides when used in antifouling paints in ships. Considering these, it can be observed the necessity to develop a new algaecide to overcome the failings of leaching of the compounds used nowadays. Material as organoclay is an excellent alternative because they are highly hydrophobic. Therefore in this work was synthesized a new nanomaterial using benzalkonium chloride, which was applied in a house paint formulation. The material was characterized by the techniques of X-ray diffraction and thermogravimetric analysis. A film coating was placed in a leaching chamber, simulating the action of rain. After leaching the coating film was applied to microbiological tests to check if the surface still had microbial protection against the following algae species: Phormidium cebenense, Trentepohlia odorata, Chlorella sp and Scenedesmus quadricauda; placed in a pool of algae. It was possible to determine the structure and quantify the amount of benzalkonium chloride in the material through X-ray Diffraction and Thermogravimetric analysis, respectively. The biocide capabilities as well as the resistance to weathering of coating with the material were analyzed by microbiological and leaching test, respectively. The new compound developed in this study has a high potential to be used as microbial agent in paints.
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Haloui, Abdallah. "Libération dans l'eau des produits chimiques utilisés pour la préservation du bois : modélisation et expérimentation." Saint-Etienne, 1995. http://www.theses.fr/1995STET4017.

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La méthode couplant l'expérimentation et la modélisation est utilisée pour étudier le processus d'absorption et de désorption du méthanol avec un transfert tridimensionnel dans le bois. Le méthanol est un bon solvant pour fixer certains produits fongicides à l'intérieur du bois, car le bois est un matériau qui peut être attaqué par des champignons, c'est pourquoi on le soumet à un traitement en profondeur par des produits fongicides, ce qui lui permet d'être utilisé dans les milieux les plus défavorables. Le traitement du bois est indispensable mais pas suffisant car un problème apparait lorsque l'échantillon de bois traité est placé dans l'eau, il s'agit de la libération qui prend place, avec deux inconvénients ; une pollution de l'eau et une diminution de la résistance du bois envers les champignons. Des modèles mathématiques basés sur une méthode numérique aux différences finies ont été construits pour décrire les transferts du méthanol dans le bois et d'autres pour décrire la libération du produit chimique dans l'eau. Ces modèles permettent de simuler les cinétiques de transfert et fournir plus d'information que les expériences
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Brand, Simone Cristiane. "Isolamento e identificação de substâncias provenientes da laranjeira ´Valência` (Citrus sinensis) envolvidas no estímulo e/ou quebra da dormência de estruturas quiescentes de Colletotrichum acutatum, agente causal da podridão floral dos citros." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-23032012-165119/.

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A podridão floral dos citros (PFC), causada por Colletotrichum acutatum, induz a abscisão de frutos jovens, podendo causar perdas de até 100%. A presença de inóculo viável na forma de conídios e/ou apressórios quiescentes na planta justifica a ocorrência generalizada da doença. Em períodos de chuva a PFC é agravada, possivelmente, em função de substâncias lavadas das diferentes partes da planta, as quais contêm metabólitos que estimulam o desenvolvimento do fungo. Diante do exposto, objetivou-se verificar o efeito das águas de lavagem brutas (ALBs) de flores, botões, folhas velhas (FV) e folhas novas (FN) e mistura destas sobre conídios, apressórios e hifas quiescentes de C. acutatum (isolados 61A e 142) in vitro e in vivo e sobre a severidade da PFC, bem como identificar substâncias presentes nas ALBs, exibindo a atividade biológica de interesse. Além disso, buscou-se verificar variações na composição das ALBs. O efeito de compostos voláteis brutos (CVBs) e os identificados a partir de laranjeira Valência (linalol, limoneno, mirceno, nonanal e a mistura destes) sobre o desenvolvimento do patógeno também foi avaliado. Todas as frações das ALBs estimularam a germinação dos conídios do fungo, sendo que a ALB de flores apresentou o maior estímulo para ambos os isolados. Para apressórios quiescentes (isolado 61A), o maior estímulo foi verificado nos tratamentos com ALBs de botões e da mistura e para conídios no tratamento mistura. Os maiores valores para comprimento do tubo germinativo foram observados nos tratamentos mistura, FN e botões. Para as estruturas quiescentes, o efeito das ALBs foi mais significativo para o isolado 142. Não foi observado efeito das ALBs sobre o micélio quiescente. Houve estímulo da germinação de conídios e ramificação de hifas in vivo, principalmente, em resposta ao tratamento com ALB de botões. A aplicação da ALB da mistura em flores resultou em maior severidade da PFC. Por sua vez, os CVBs apresentaram efeito inibitório. A exposição do isolado 61A aos voláteis (CVs) linalol, nonanal e mistura, resultou em germinação apenas na menor dose. O mirceno manteve a germinação semelhante a testemunha em todas as doses testadas, assim como limoneno nas doses de 0,005 a 0,25 µL mL-1. Todos os voláteis reduziram o comprimento do tubo germinativo. Para o isolado 142, houve redução em todas as variáveis para todas as doses dos CVs. Houve variações na composição das ALBs nas diferentes coletas, o que explica em parte a variação na capacidade de estímulo em alguns testes. Na ALB de flores, identificou-se a presença de cafeína, dos flavonóides glicosilados hesperidina e naringina, além de compostos glicosilados e peptídeos. Nas partes vegetais de laranjeira Valência foram identificados 54 CVs. As ALBs apresentam efeito estimulatório sobre conídios e apressórios quiescentes de C. acutatum in vitro e in vivo, bem como sobre a severidade da PFC. Os CVs linalol, limoneno, mirceno, nonanal e a mistura destes são, de forma geral, inibitórios ao desenvolvimento de C. acutatum.<br>The postbloom fruit drop of citrus (PFDC), caused by Colletotrichum acutatum, induces abscission of young fruits, and it may cause losses up to 100%. The presence of viable inoculum in the form of conidia and/or quiescent appressoria on the plant justifies the widespread occurrence of the disease. Under rain, the PFDC is increased, possibly due to substances washed from different parts of the plant, which contain metabolites that stimulate the development of the fungus. Therefore, we aimed to determine the effect of watery washing (WWs) of flowers, flower buds, old leaves (OL) and young leaves (YL) and the mixture of them on quiescent conidia and hyphae of C. acutatum (isolates 61A and 142) in vitro and in vivo and on the severity of the PFDC, and to identify substances in the WWs, exhibiting the biological activity of interest. In addition, variations in the composition of WWs were determinated. The effect of crude volatile compounds (CVCs) and those identified from Valencia sweet orange (linalool, limonene, myrcene, nonanal and the mixture of them) on the development of the pathogen was also evaluated. All fractions of WWs stimulated spore germination, and the flower WW exhibited the highest effect for both isolates. For quiescent appressoria (isolate 61A), the highest stimulus was observed in treatments with WWs from flower buds and the mixture and for quiescent conidia in the treatment mixture. The highest values for germ tube length were observed on the treatments mixture, YL and flower buds. For the quiescent structures, the effect of WWs was more significant for isolate 142. There was no effect of WWs on the quiescent mycelium. There was stimulation of conidia germination and hyphal branching in vivo in response mainly to treatment with WW from flower buds. The application of the mixture of WW in flowers resulted in higher severity of the PFDC. On the other hand, the CVCs showed inhibitory effect. Exposure of the isolate 61A to the volatiles (VCs) linalool, nonanal and the mixture of them, resulted in germination only at the lowest concentration. The germination on myrcene was similar to control at all doses tested as well as on limonene at doses from 0.005 to 0.25 mL mL-1. All volatiles reduced the length of the germ tube. In the case of isolate 142, a reduction in all variables for all concentration of VCs was observed. There were changes in the composition of WWs based upon times of harvesting, which partly explains the variations observed in the ability to stimulate the structures in some experiments. In flower WWs, we identified the presence of caffeine, the flavonol glycosides hesperidin and naringin, glycosylated compounds and peptides. In the plant parts of sweet orange \'Valencia\' were identified 54 VCs. The WWs have stimulatory effect on quiescent conidia and appressoria of C. acutatum in vitro and in vivo as well as in the severity of the PFDC. The VCs linalool, limonene, myrcene, nonanal and the mixture of them are, in general, inhibitory to the development of C. acutatum.
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De-huang, Huang, and 黃德煌. "Leaching Behaviors of Copper Oxide Solidification/Stabilization Using Calcium Silicate Fixing Agent." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/96247005912477933125.

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黃德煌. "Leaching behaviors of copper oxide solidification/stabilization using calcium silicate fixing agent." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/50069932569240171299.

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Rybínová, Marcela. "Speciační analýza chromu v prachových částicích." Master's thesis, 2010. http://www.nusl.cz/ntk/nusl-285170.

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Anion-exchange chromatography with inductively coupled plasma - atomic emission spectrometry (ICP-AES) has been used for the speciation of chromium (Cr). Chromium speciation has attracted attention because of the different toxicity, Cr(III) is relatively non-toxic and Cr(VI) has been classified as a human carcinogen. The aim of the present study was to develop simple method for the speciation analysis of Cr (Cr(III) and Cr(VI)) in particulate matter of urban dust. A combination of 2% KOH + 3% Na2CO3 has been chosen as the optimal reagent for the extraction of chromium from particular matter. It was found that there was no conversion of Cr(VI) into Cr(III). The effect of separation parameters such as acidity of mobile phase was also studied. The detection limit for Cr(VI) was about 12 ng.ml-1 . Results for the determination of Cr(VI) were confirmed by the analysis of standard reference material (BCR CRM 545, Cr(VI) in welding dust loaded on a filter) with good agreement between certified (40,16 ± 0,60 μg.g-1 ) and found (37,83 ± 1,14 μg.g-1 ) values.
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Напольских, Ю. А., та Y. A. Napol’skikh. "Извлечение тяжелых цветных металлов из шламов нейтрализации отработанных электролитов : магистерская диссертация". Master's thesis, 2018. http://hdl.handle.net/10995/65160.

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В данной работе проведено исследование переработки мышьяксодержащих шламов нейтрализации отработанных электролитов с целью селективного извлечения ценных металлов (медь, никель). Для определения химического и фазового анализа техногенного многокомпонентного сырья применены методы спектрофотометрии (AAС) и рентгенофазовой дифрактоскопии. Предложен выщелачивающий комплексообразующий реагент Трилон Б и обоснован его выбор. Проведены литературный обзор современных методов переработки, лабораторные исследования. Исследованы и оптимизированы процессы выщелачивания шламов водным раствором Трилона Б, очистки полученного трилонатного раствора от металлов-примесей, регенерации растворителя. Так же в диссертации выбрана оптимальная схема переработки гидроксидных шламов и отражено эколого-экономическое обоснование выбранной технологии переработки.<br>In this paper, research arsenic-containing slimes of neutralization of waste electrolytes was carried out to selectively extract valuable metals (copper, nickel). The method of Atomic Absorption Spectroscopy (AAS), X-ray Diffraction (XRD) was applied. The chemical and phase analysis of multicomponent manmade waster was carried out, the leaching chelating reagent Trilon B was offered and its choice is reasonable. A review of modern methods of processing and laboratory studies were carried out. The processes of leaching of slimes by aqueous solution of Trilon B, purification of the obtained trilonate solution from metal-impurities and solvent regeneration were studied and optimized. Also, in the thesis the optimal scheme of processing of hydroxide sludges was chosen and the ecological and economic justification of the chosen technology of processing was represented.
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Старков, А. М., та A. M. Starkov. "Исследование физико-химических свойств нового композитного сорбента : магистерская диссертация". Master's thesis, 2018. http://hdl.handle.net/10995/65162.

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Объектом исследования является композитный сорбент, модифицированный оксигидратом железа. Цель работы - синтез композитного неорганического сорбента и изучение его свойств. В работе проводился синтез нового неорганического сорбента с помощью полного факторного эксперимента. Был изучен механизм сорбции ионов фтора и хлора. Изучена устойчивость сорбента к агрессивным средам. Экспериментально определена емкость различных образцов сорбента.<br>In this paper, research arsenic-containing slimes of neutralization of waste electrolytes was carried out to selectively extract valuable metals (copper, nickel). The method of Atomic Absorption Spectroscopy (AAS), X-ray Diffraction (XRD) was applied. The chemical and phase analysis of multicomponent manmade waster was carried out, the leaching chelating reagent Trilon B was offered and its choice is reasonable. A review of modern methods of processing and laboratory studies were carried out. The processes of leaching of slimes by aqueous solution of Trilon B, purification of the obtained trilonate solution from metal-impurities and solvent regeneration were studied and optimized. Also, in the thesis the optimal scheme of processing of hydroxide sludges was chosen and the ecological and economic justification of the chosen technology of processing was represented.
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Books on the topic "Leaching agent"

1

Ma, Te-hsia. Genotoxicity of gaseous agents and leachates from a landfill and the air around and incinerator. University of Illinois at Urbana-Champaign, Office of Solid Waste Research, Institute for Environmental Studies, 1993.

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Sandoval, S. P. Effect of nonionic surfactants on chalcopyrite leaching under dump chemical conditions. U.S. Dept. of the Interior, Bureau of Mines, 1991.

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Sandoval, S. P. Effect of nonionic surfactants on chalcopyrite leaching under dump chemical conditions. U.S. Dept. of the Interior, Bureau of Mines, 1991.

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Sandoval, S. P. Effect of nonionic surfactants on chalcopyrite leaching under dump chemical conditions. U.S. Dept. of the Interior, Bureau of Mines, 1990.

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Sandoval, S. P. Effect of nonionic surfactants on chalcopyrite leaching under dump chemical conditions. Dept. of the Interior, 1990.

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Owusu, George. The Role of surfactants in the leaching of zinc sulphide minerals at temperatures above the melting point of sulphur. University of British Columbia, 1993.

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C, Kraft N., Mandler J. W, U.S. Nuclear Regulatory Commission. Office of Nuclear Regulatory Research. Division of Regulatory Applications., Idaho National Engineering Laboratory, and EG & G Idaho., eds. Compression and immersion tests and leaching of radionuclides, stable metals, and chelating agents from cement-solidified decontamination waste collected from nuclear power stations. Division of Regulatory Applications, Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory Commission, 1994.

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Book chapters on the topic "Leaching agent"

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Kedziorek, Monika A. M., Fabrice Compère, Alain Dupuy, and Alain C. M. Bourg. "Heavy Metal Leaching from Contaminated Soils during the Percolation of EDTA: Observations and Modeling." In Chelating Agents for Land Decontamination Technologies. American Society of Civil Engineers, 2012. http://dx.doi.org/10.1061/9780784412183.ch07.

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Sumalatha, J., R. Prabhakara, and P. V. Sivapullaiah. "Removal Efficiency of Heavy Metals by Washing the Contaminated Soil Using Effective Leaching Agents." In Lecture Notes in Civil Engineering. Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-5195-6_76.

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Sato, A., and S. Nishimoto. "Reduction in leaching of hazardous substances from coal ash by addition of solidification agent." In Stabilisation/Solidification Treatment and Remediation. Taylor & Francis, 2005. http://dx.doi.org/10.1201/9781439833933.ch17.

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Ibrahim, Ahmad, Joseph-Émile Laquerre, Patricia Forcier, Vincent Deregnaucourt, Justine Decaens, and Olivier Vermeersch. "Antimicrobial Agents for Textiles: Types, Mechanisms and Analysis Standards." In Textiles for Functional Applications [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.98397.

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The large surface area, and ability to retain moisture of textile structures enable microorganisms’ growth, which causes a range of undesirable effects, not only on the textile itself, but also on the user. Moreover, textiles used in health care environments are required to possess antimicrobial property to minimize spread of pathogenic infection. Anti-microbial property can be imparted via chemical finishing with an antimicrobial agent. Currently the use of antimicrobial agents includes metal compounds (notably copper and silver particle), chitosan, halogenated phenols “triclosan”, quaternary ammonium compounds, antibiotics (a class of antimicrobials produced from microorganisms that act against one another), and N-halamines. The possibility of bacterial resistance limits antibiotic use to specific medical applications, and triclosan is known for being dangerous to the environment and is currently under scrutiny for possible endocrine disrupting to human being. Although quaternary ammonium compounds are stable and easily manufactured, microbial resistance is also a concern. Quaternary ammonium compounds (QACs), Polyhexamethylene Biguanide (PHMB), chitosan and N-halamines are listed under bound or non-leaching type antimicrobials. The bulk of current chapter focuses on the different family of antimicrobial agents used for textiles and their mechanisms.
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I. Abu-Eishah, Samir, Manal D.M. Raheem, Fatma A.S. Aljasmi, Fatima M.O. Alameri, Amna G.R. Alblooshi, and Intesar F.R. Alnahdi. "A Zero-Waste Process for the Treatment of Spent Potliner (SPL) Waste." In Current Topics in Recycling [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.99055.

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This work presents a deep analyses of an environmentally friendly process to recover all valuable minerals contained in the spent potliner (SPL) such as graphite carbon and aluminum fluoride (AlF3) and production of sodium sulfate (Na2SO4) and gypsum (CaSO4) when H2SO4 is used as the leaching agent. The level of emission of hazardous gases such as HCN (weak acid) and HF are minimized by direct scrubbing of the HCN in aqueous AgNO3 solution to produce a stable silver cyanide (AgCN) product. The HF can be recovered as a liquid by condensation and used within the process and/or in production of metal fluorides such as the highly-soluble potassium fluoride (KF); a main source of fluoride in industry. Almost pure CO2 gas is also recovered from the process gas streams.
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Garrabrants, Andrew C., and David S. Kosson. "Use of a Chelating Agent to Determine the Metal Availability for Leaching From Soils and Wastes." In Studies in Environmental Science. Elsevier, 1997. http://dx.doi.org/10.1016/s0166-1116(97)80206-3.

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"Effect of Plant Growth Promoting Bacteria (PGPB) on Phytoremdiation Technology." In Nano-Phytoremediation Technologies for Groundwater Contaminates. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-5225-9016-3.ch005.

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In this chapter, the authors describe how plant-growth-promoting bacteria is helpful for removing soil contaminants and also increasing the efficiency of phytoremediation technology. The plant growth bacteria seem almost good for removal of soil contaminants, and they can adsorb and accumulate metals in their cells and are being used in microbial leaching and also as agents of cleaning the environment.
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"Factors That Influence Toxicity." In Environmental Toxicology, edited by Sigmund F. Zakrzewski. Oxford University Press, 2002. http://dx.doi.org/10.1093/oso/9780195148114.003.0009.

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The more species are removed from each other in evolutionary development, the greater is the likelihood of differences in response to toxic agents. One obvious difference that affects toxicity is the size of the organisms. Much less toxin is needed to kill a small insect than a considerably larger mammal (everything else being equal). In addition, there is an inverse relationship between the weight of an animal and its surface area; the smaller the animal, the larger its surface area per gram of weight. Thus, the weight ratio of a human being (70 kg) to a rat (200 g) is 350, but the surface area ratio of a human being to a rat is only 55. Roughly, the surface area of an animal (S) can be calculated as follows: S(m2) = weight (kg)2/3/10. This type of calculation is important when one is considering the selective eradication of an uneconomical species, such as certain insects, by spraying an area with insecticide. The goal is to control the insects without harming wildlife, livestock, and human beings. Other factors, such as the rate of percutaneous absorption, also have to be considered. For instance, it has been shown that DDT (dichlorodiphenyltrichloroethane) is about equally toxic to insects and mammals when given by injection, yet when applied externally it is considerably more toxic to insects. This toxicity is due not only to the difference of the surface area:- body weight ratio, but also to the fact that the chitinous exoskeleton of the insect is more permeable to DDT than unprotected mammalian skin (1). Of course, in real-life situations (i.e., outside the laboratory), most mammalian skin is covered by fur, which gives the animals additional protection. The foregoing discussion is not meant to imply that unrestricted spraying with pesticides (especially chlorinated hydrocarbons, which are fat-soluble and poorly biodegradable) is environmentally sound. Problems with their use include lack of selectivity among insect species; leaching into watersheds and groundwater; and bioaccumulation in the food chain. These problems will be discussed in detail in Chapter 11. Metabolic-pathway differences among species may provide another rationale for achieving selective toxicity
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Conference papers on the topic "Leaching agent"

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Yang, Fengyun, Yaming Zhao, Luanning Li, Shujie Zhao, Yuguo Cui, and Hongwei Liang. "Research and application of a 3YL non-cyanide gold leaching agent." In International Conference on Earth Science and Environmental Protection (ICESEP2013). WIT Press, 2013. http://dx.doi.org/10.2495/icesep130991.

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Liao, Wensheng, Weimin Que, Liming Wang, and Zhiming Du. "Synergetic Oxidation in Alkaline In-Situ Leaching Uranium: A Preliminary Case Study." In 2020 International Conference on Nuclear Engineering collocated with the ASME 2020 Power Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/icone2020-16200.

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Abstract In alkaline in-situ leaching uranium, oxygen is the most common oxidizer with bicarbonate as a complexing agent. For those sandstone uranium deposits with strongly reductive capacity or complicated hydrogeological environment, the oxidation by oxygen is low efficiency. An efficient leaching method, therefore, is needed for these uranium deposits. In this study, a typical sandstone uranium deposit which characterizes with high TDS and high chloride content in groundwater and intractable uranium leach is selected to investigate the effects of synergetic oxidation by a strong oxidant with oxygen. Based on the research on batch leach, pressure leach and field trials, the oxidants such as hydrogen peroxide, potassium permanganate and sodium dichloroisocyanurate (NaDCC) are tested. The results of pressure batch leach indicate that synergetic oxidization is achieved by NaDCC in oxygen leaching process. Leaching tests indicate that a minor oxidizer of NaDCC shows good synergetic oxidization with oxygen and leaching effects on uranium minerals. The results also demonstrate that hydrogen peroxide shows no oxidation effects when it is used as a single oxidant. While potassium permanganate shows good oxidation on uranium when it is used as a single oxidant, however, it leads inhibiting effects on oxygen oxidation on uranium minerals. The further field tests are conducted to study the synergetic effects of oxygen with and without sodium dichloroisocyanurate. The preliminary results indicate that a fast leach is observed by the composite oxidants in early stage while no synergetic leach is found after 200 days. Further studies should be conducted in laboratory experiments and pilot scale tests for its potential applications.
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Vilarinho, Cândida, José Teixeira, Jorge Araújo, and Joana Carvalho. "Effect of Time and Acid Concentration on Metal Extraction From Galvanic Sludges." In ASME 2017 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/imece2017-71370.

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Galvanic sludge is a solid waste produced by the surface treatment industry, classified as hazardous because of their high concentration of heavy metals, which in its final destination is disposed in waste disposal facilities, with economic costs to the holders. Through hydrometallurgical processing, it is possible to extract valuable metals, with low costs involved, while the hazardous level of the residue is reduced. In the present work, the heap leaching method was studied as a solution to the treatment of these residues, which in order to consist in a valuable option, processing and operation costs must be kept as low as possible. For the experimental testing, a closed loop lixiviation column for hydrometallurgical treatment of galvanic sludge with possibility of continuous flow of the leachate (and static process as well) was constructed, simulating the heap leaching process. The galvanic waste in study, delivered by a local surface treatment company, was both chemically and physically characterized, proving to be rich in valuable metals like Nickel, Chromium and Copper. The waste material was characterized both for physical parameters (grain size) and chemical composition. The lixiviation trials, with a maximum duration of 1 week, were conducted. The influence upon the extraction rate of metals such as Nickel, Chromium and Copper, of parameters such as the concentration of the leaching agent (sulfuric acid) and time were tested. In order to quantify the leachate circulation effect, a static trial was conducted as well. Extraction rates of 35.5 % of Nickel, 14% of Copper and 13.6 % of Chromium were obtained after 6 hours in a dynamic trial, with 100 g/L sulfuric acid solution concentration. The acid consumption rate was correlated with the metal extraction. Finally, the results were compared with others obtained in previous galvanic sludge agitation lixiviation and laterites heap leaching works.
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Shih, Chien-Jen, Keith E. Forrester, and Wen-Bin Fan. "Application of Dry Chemical Stabilization Technology in Taiwan Kobin Bottom Ash Processing and Recycle Plant." In 14th Annual North American Waste-to-Energy Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/nawtec14-3191.

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The Taiwan Kobin Bottom Ash Processing &amp; Recycle Plant (Kobin-BAPRP) processes approximately one quarter million metric tons of bottom ashes from several municipal solid wastes the incinerators annually, generating fine aggregate finished products and ferrous recovery. The results from USEPA Method 1311 Toxicity Characteristic Leaching Procedure (TCLP) for un-treated bottom ash indicate that about 5% of the time that lead and less than 0.5% of the time, copper or cadmium may fail to meet leaching standards (i.e. 5 mg/L for Pb, 15 mg/L for Cu, and 1 mg/L for Cd ). Previously, Kobin applied phosphoric acid solution for stabilization, which caused strong odor problem, increased moisture content, and still about 1% of the time that TCLP-Pb failed to pass the standard, hence, required reprocessing. Recently, Kobin-BAPRP has switched its stabilization agent from the phosphoric acid solution to dry chemical dosage. In addition to having a better stabilized byproduct, the use of dry chemical further ensures worker safety. Dry chemical is water insoluble and fine calcium phosphate particles, with different combinations of buffers and complexing agents, such as Fe+2, Fe+3, Al+3, or chloride. It took about 8 months for laboratory tests and plant trials to identify the optimum dosage as well as the best mixing point. Long term operation has demonstrated that dry chemical spread and mixing is safe to communities and workers, non-reactive with storage and handling materials, generates no toxic gases or odor, and most importantly, provides for effective and consistent Pb stabilization. The final stable family of mineral crystals includes complexed hydroxyapatite and chlorapatite minerals.
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"Recovery of Base Metals from Mine Tailings Dumps collected in the Vicinity of Potchefstroom: Leaching assisted by Complexing Agent." In 7th International Conference on Latest Trends in Engineering and Technology. International Institute of Engineers, 2015. http://dx.doi.org/10.15242/iie.e1115026.

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Guerrero, Hector N., Mark D. Fowley, and David J. Sherwood. "Irradiation and Temperature Effects on Anti-Foam Agent Performance in a Non-Newtonian Waste Slurry Simulant." In ASME 2009 Fluids Engineering Division Summer Meeting. ASMEDC, 2009. http://dx.doi.org/10.1115/fedsm2009-78247.

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Foaming tests were performed in a bench-scale foam column and 1/9th-scale mechanically-agitated mixing system at the Savannah River National Laboratory (SRNL) for a simulant of waste slurry from the Hanford Tank 241-AZ-101. This featured additions of DOW Corning Q2-3183A antifoam agent (AFA) to prevent foaming, especially in the evaporators. These waste slurries (typically 15 wt% solids) are particularly prone to particle-stabilized foaming. Previous studies have shown that up to 20% of the polydimethyl siloxane (PDMS) portion of the AFA mixture is degraded by radiation. The high temperature (90°C) for 48 hrs of a caustic leaching process may have a similar effect on the polymer. The objective of this study was to determine how well degraded AFA works. Key results are that: • Without addition of this AFA, the 1/9th-scale system had about 100% foaming at 1 mm/s air velocity and the bench-scale system had over 400% foaming for an air flow of 10 mm/s. • The effect of irradiating 350 ppm AFA was to increase foaming from 6% to 30% in the foam column and 7.6% to 13.7% in the 1/9th-scale system at an air flow of 1 mm/s at room temperature. • The effect of heating the AFA to 90°C was to increase foaming by a factor of 1.6 in the foam column. But while the effectiveness of the irradiated AFA was reduced, it still provided a significant reduction in foaming. AFA additions required to mitigate the combined effects of high temperature and radiation were also determined.
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Dianu, Magdalena, and Nicolela Deneanu. "Conditioning Experiments of Organic Solvents Solutions Contaminated With Tritium." In ASME 2003 9th International Conference on Radioactive Waste Management and Environmental Remediation. ASMEDC, 2003. http://dx.doi.org/10.1115/icem2003-4740.

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The method consists in the conditioning of organic solvents solutions contaminated with tritium (acetone, ethylene alcohol, methanol, trichloromethane, toluene, white spirit) into a cement and proper solidification additives matrix. Portland cement is the most common type of hydraulic cement and is the original agent utilized for the solidification of low-level radioactive waste. The paper contents: • the characterization of conditioning matrix components: waste, cement, additives; • preliminary laboratory tests on waste, cement and additives; • mechanical resistance verifications of conditioning matrix (results, tables); • leaching tests for tritium (results, graphs). This method is very simple, with low cost of working materials and long shelf life of working materials. The operator exposure is negligible because there is not any vapor problem. The values of mechanical resistance are higher than the disposal minimal value. Rate of release of tritium from the waste form as a result of interaction with water is very low. The higher values of mechanical resistant and the low rate of tritium released from the waste form offer security for transportation and final disposal of the waste placed in cement.
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Park, Jong Woon, Byung Gi Park, and Chang Hyun Kim. "Investigation of Chemical Effects on Emergency Core Cooling Filtration Head Loss After Loss of Coolant Accident." In 17th International Conference on Nuclear Engineering. ASMEDC, 2009. http://dx.doi.org/10.1115/icone17-75398.

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Integrated tests of head loss through an emergency core cooling filter screen are conducted, simulating reactor building environmental conditions for thirty days after a loss of coolant accident. A test apparatus with five individual loops each of whose chamber is established to test chemical product formation and measure the head loss through a sample filter. The screen area at each chamber is 78.54cm2 and reactor building materials can be scaled down according to specific plant condition. A series of tests have been performed to investigate the effects of reactor building spray, existence of calcium-silicate with tri-sodium phosphate (TSP), and composition of materials. The results showed that head loss across the chemical bed with even a small amount of calcium-silicate insulation instantaneously increased as soon as TSP was added to the test solution. Also, the head loss across the filter screen is strongly affected by spray duration and the head loss increase is rapid at the early stage, because of high dissolution and precipitation of aluminum and zinc. After passivation of aluminum and zinc by corrosion, the head loss increase is much slowed down and is mainly induced by materials such as calcium, silicon, and magnesium leached from NUKON™ and concrete. Furthermore, it is newly found that the spay buffer agent, tri-sodium phosphate, to form protective coating on the aluminum surface and reduce aluminum leaching is not effective for a large amount of aluminum and a long spray.
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Villa, Lina, Nestor Rojas, and Wilmer Saldarriaga. "Comparative Analysis of Different Carboxylic Leaching Agents for Lead Battery Recycling." In The 3rd World Congress on Mechanical, Chemical, and Material Engineering. Avestia Publishing, 2017. http://dx.doi.org/10.11159/mmme17.120.

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Khan, Mariam, Mohammad Al ghouti, Mustafa Nasser, Khalid Al Kuwari, and Oon Heng. "A study comparing Conventional Heating and Microwave Assistance Heating to Recover Metals from Municipal Solid Waste using Microwave-Assisted Leaching Technique." In Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2020. http://dx.doi.org/10.29117/quarfe.2020.0027.

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This study investigates and compares microwave-heating radiation with conventional heating. Incinerated municipal solid waste (IMSW) bottom ash (BA) and fly ash (FA) was utilized to recover various metals including Co, Cr, Cu, Fe, Mn, Zn,Pb, Al, Cd, Ba, Mg and V using various acid leaching agents i.e. HCl, HNO3 and H3PO4 were utilized and several parameters were altered in order to determine the most effective conditions. The current study concluded that microwave assisted leaching method is effective to recover most of the metals. In addtion, metals from MSWBA were much easier to recover in contrast with MSW-FA. 71% of Co, 75.69% of Cr, 56.19% of Cd, 35.23% of Ba and 30.2% of Pb, using 2M of HCl and 3M of H3PO4. While 1.48% of Cr, 0.93% of Fe, 1.19% of Mn, and 1.18% of Al were extracted using HCL and H3PO4 from MSWFA. It was also confirmed that higher power and longer contact time had a positive effect on metal recovery. From cost analysis point of view, microwave assisted leaching was fraction of the cost for conventional heating, making this method comparatively sustainable, energy efficient and safe.
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Reports on the topic "Leaching agent"

1

Rapko, Brian M., Susan A. Jones, Gregg J. Lumetta, and Reid A. Peterson. Effect of Antifoam Agent on Oxidative Leaching of Hanford Tank Sludge Simulants. Office of Scientific and Technical Information (OSTI), 2010. http://dx.doi.org/10.2172/972943.

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2

Spencer, B. B. Caustic Leaching of SRS Tank 12H Sludge With and Without Chelating Agents. Office of Scientific and Technical Information (OSTI), 2003. http://dx.doi.org/10.2172/885758.

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3

Akers, D. W., N. C. Kraft, and J. W. Mandler. Compression and immersion tests and leaching of radionuclides, stable metals, and chelating agents from cement-solidified decontamination waste collected from nuclear power stations. Office of Scientific and Technical Information (OSTI), 1994. http://dx.doi.org/10.2172/10163389.

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