The Experts below are selected from a list of 1320 Experts worldwide ranked by ideXlab platform
Jae Chun Lee - One of the best experts on this subject based on the ideXlab platform.
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Bioleaching of metals from Electronic Scrap in a stirred tank reactor
Hydrometallurgy, 2014Co-Authors: Sadia Ilyas, Jae Chun LeeAbstract:Abstract The purpose of the present work was to investigate the effect of aeration, O 2 , CO 2 , agitation, various sulfur types and dosages and pulp density on the growth of Sulfobacillus thermosulfidooxidans and bioleaching efficiency of Electronic Scrap in stirred tank reactors. Sulfur bioavailability, metabolism, and oxidation degree were also evaluated. The leaching trends show that the optimum extraction of metals in media-1 supplemented using biogenic S 0 were observed using 25% O 2 + 0.03% CO 2 enriched air at a 2.5% S 0 dosage with an overall leaching of 91% Al, 95% Cu, 96% Zn and 94% Ni at a 10% pulp density compared to 74% Al, 81% Cu, 83% Zn and 78% Ni using 30% O 2 + 2% CO 2 enriched air at a 3.5% S 0 dosage and 10% pulp density with technical sulfur supplementation in media-2. The FT-IR and XANES analyses indicate a significant modification of the spectra of the technical and biogenic sulfur due to the addition of several new groups (− NH , − OH, − S(= O) 2 −, − SO 2 − O − , − CH 3 , or − CH 2 ) and the presence of polythionates, C–S–H, sulfanes and sulfonate species in both media at different degrees and time period. The significantly higher PEP carboxylase activity (5.1 nmol/min mg protein) in media-1 and PEP carboxykinase and pyruvate carboxylase activities (1.10 and 0.5 nmol/min mg protein) in media-2 indicates different preferential modes of growth. An economical feasibility study indicated that the results of the leaching process might have the potential for increased scale.
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Removal of chromium(VI) from the leachate of Electronic Scrap using non-ionic Amberlite XAD-7HP resin
Journal of Chemical Technology and Biotechnology, 2013Co-Authors: Nghiem V. Nguyen, Jinki Jeong, Jae Chun LeeAbstract:Background In order to recover the valuable metals from the leach liquor of Electronic Scrap, it is necessary to remove/recover chromium(VI) due to its high toxicity. The non-ionic ion exchange resin, Amberlite XAD-7HP has been employed in the present research to remove Cr(VI) as it possesses large surface area and porosity to adsorb chromium selectively from complex leach solutions in the presence of other ionic species. Results Amberlite XAD-7HP resin effectively adsorbed chromium in the range of acidity from 0.3 to 2.0 mol L−1. The sorption capacity was found to be 16.9 mg Cr g−1 resin in 30 min under the experimental conditions used. Studies carried out with actual leach solution containing Cu, Zn, Ni, Sn, Pb, Au, Cd and Cr showed the selective adsorption of both Cr and Au as they are present in the solution in an anionic form. Cr was then selectively eluted with water/dilute sodium hydroxide from the loaded resin. Subsequently, Au could be eluted with mixed solution of hydrochloric acid and acetone to regenerate the resin for recycle. Conclusion Amberlite XAD-7HP resin is suitable and effective for the removal of Cr(VI) from complex leachate of Electronic Scrap. The other associated metals in the leach solution could be recovered in subsequent steps generating a final solution which could be discharged to the environment.
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Bioleaching of metals from Electronic Scrap and its potential for commercial exploitation
Hydrometallurgy, 2012Co-Authors: Sadia Ilyas, Jae Chun Lee, Ru-an ChiAbstract:Abstract In this study, ability of moderately thermophilic bacterial consortium to extract metals from Electronic Scrap was evaluated using shake flasks and lab-scale column reactor. We investigated the effects of having additional energy source (FeS2, S0, FeS2 + S0), using different consortia of moderately thermophilic bacteria and washing charge material as a pretreatment. At Scrap concentrations of 10%, an adapted consortium of Sulfobacillus thermosulfidooxidans and Thermoplasma acidophilum extracted approximately 85% of Cu, 75% of Al, 80% of Ni and 80% of Zn from pretreated Electronic Scrap with FeS2 + S0 (1%). However, a consortium of S. thermosulfidooxidans and Sulfobacilllus acidophilus, containing FeS2 + S0, extracted 90% of Cu, 80% of Al, 82% of Ni and 85% of Zn. During column bioleaching studies of 165 days, approximately 74% Zn, 68% Al, 85% Cu, 78% Ni was leached out. The results of the leaching process are significant for understanding how to implement these processes on an industrial scale.
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Removal of chromium(VI) from the leachate of Electronic Scrap using non‐ionic Amberlite XAD‐7HP resin
Journal of Chemical Technology & Biotechnology, 2012Co-Authors: Nghiem Van Nguyen, Jinki Jeong, Jae Chun LeeAbstract:Background In order to recover the valuable metals from the leach liquor of Electronic Scrap, it is necessary to remove/recover chromium(VI) due to its high toxicity. The non-ionic ion exchange resin, Amberlite XAD-7HP has been employed in the present research to remove Cr(VI) as it possesses large surface area and porosity to adsorb chromium selectively from complex leach solutions in the presence of other ionic species. Results Amberlite XAD-7HP resin effectively adsorbed chromium in the range of acidity from 0.3 to 2.0 mol L−1. The sorption capacity was found to be 16.9 mg Cr g−1 resin in 30 min under the experimental conditions used. Studies carried out with actual leach solution containing Cu, Zn, Ni, Sn, Pb, Au, Cd and Cr showed the selective adsorption of both Cr and Au as they are present in the solution in an anionic form. Cr was then selectively eluted with water/dilute sodium hydroxide from the loaded resin. Subsequently, Au could be eluted with mixed solution of hydrochloric acid and acetone to regenerate the resin for recycle. Conclusion Amberlite XAD-7HP resin is suitable and effective for the removal of Cr(VI) from complex leachate of Electronic Scrap. The other associated metals in the leach solution could be recovered in subsequent steps generating a final solution which could be discharged to the environment.
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Recovery of Cu and Sn from waste electrical and Electronic Scrap utilizing waste copper slag
Journal of Metallurgy and Materials Science, 2009Co-Authors: Byung-su Kim, Jinki Jeong, Jae Chun Lee, Seongwon Kang, Kwang Ho Lee, Nag-joon ChoiAbstract:Large amounts of waste electrical and Electronic Scrap containing considerable valuable metals such as copper, tin, gold, and silver is generated in Korea. In the view of resource recycling and to protect the environment it is necessary to recover the valuable metals from waste electric and Electronic Scrap. Present work reports a novel pyrometallurgical process for the recovery of copper and tin from the waste electrical and Electronic Scrap (WEES) by utilizing the waste copper slag as a slag formative. In each set of experiment, waste electric and Electronic Scrap were melted with waste copper slag for 30 min at 1573 K after adding suitable amount of CaO as an additional slag formative. Based on proposed process flow-sheet, >90% of copper and >80% of tin were recovered as Cu-Fe-Sn alloy from waste electric and Electronic Scrap.
Eric Forssberg - One of the best experts on this subject based on the ideXlab platform.
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Recycling of Consumer Electronic Scrap
2006Co-Authors: Jirang Cui, Eric ForssbergAbstract:In the context, characterization of TV Scrap was carried out by using chemical analysis a nd particle shape analy-sis. The result of particle shape analysis indicates that the non-ferrous metals particles in TV Scrap formed as a variety of shapes, it is much more heterogenous than that of plastics and printed circuit boards. Furthermore, sepa-rability of TV Scrap was evaluated by sink-float test, air table, and optical sorting process.
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Intelligent Liberation and classification of Electronic Scrap
Powder Technology, 1999Co-Authors: Shunli Zhang, Eric ForssbergAbstract:Abstract Mechanical recycling of Electronic Scrap oriented towards overall materials recovery from obsolete Electronics is being implemented worldwide. The main reason is that the amount of Electronic Scrap is increasing and that the content of the precious metals present is decreasing. In this context, an effective liberation of various materials like metals and plastics is a crucial step towards mechanical separation. In addition, classification of Electronic Scrap is also important to be able to provide an appropriate feed material for the subsequent separation process. In the present study, liberation and its impact on the separation of personal computer (PC) Scrap and printed circuit board (PCB) Scrap has been investigated in detail. A special equipment functioning as a shape separator and an aspirator was used for the classification of Electronic Scrap.
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the investigation of separability of particles smaller than 5 mm by eddy current separation technology part i rotating type eddy current separators
Magnetic and Electrical Separation, 1999Co-Authors: Shunli Zhang, Eric ForssbergAbstract:Owing to the growing emergence of the end-of-life electrical and Electronic products with complex material structures and an ever-diminishing particle size of the valuable metals involved, development of eddy current separators (ECS) has been targeting selective separation of small non-ferrous metal particles smaller than 5 mm. Separability of various materials smaller than 5 mm, including fine copper wires, has been investigated using ECS with various design concepts. The present research work is divided into two parts, with Part focusing on the rotating type ECS which are today common in practice, and with Part II dedicated to the ECS with novel concepts such as wet ECS technology. In Part I, three rotating belted-drum ECS were employed, which are manufactured by Bakker Magnetics, the Netherlands, Huron Valley Steel Co., US, and Eriez Magnetics, UK respectively. It is found that the belted-drum ECS are effective for separating materials below 5 mm if the magnetic drum rotates in opposite direction to the conveyor belt. The separation principle, particularly the "backward phenomenon" of the rotating type ECS for small particles has been unravelled in the present study. Moreover, separation of AI from the 010 mm fraction of Electronic Scrap has been conducted. The results obtained demonstrate that the belted-drum ECS with appropriate design may be applicable for separation of small aluminum particles from Electronic Scrap.
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the investigation of separability of particles smaller than 5 mm by eddy current separation technology part i rotating type eddy current separators
Magnetic and Electrical Separation, 1999Co-Authors: Shunli Zhang, Eric ForssbergAbstract:Owing to the growing emergence of the end-of-life electrical and Electronic products with complex material structures and an ever-diminishing particle size of the valuable metals involved, development of eddy current separators (ECS) has been targeting selective separation of small non-ferrous metal particles smaller than 5 mm. Separability of various materials smaller than 5 mm, including fine copper wires, has been investigated using ECS with various design concepts. The present research work is divided into two parts, with Part focusing on the rotating type ECS which are today common in practice, and with Part II dedicated to the ECS with novel concepts such as wet ECS technology. In Part I, three rotating belted-drum ECS were employed, which are manufactured by Bakker Magnetics, the Netherlands, Huron Valley Steel Co., US, and Eriez Magnetics, UK respectively. It is found that the belted-drum ECS are effective for separating materials below 5 mm if the magnetic drum rotates in opposite direction to the conveyor belt. The separation principle, particularly the "backward phenomenon" of the rotating type ECS for small particles has been unravelled in the present study. Moreover, separation of AI from the 010 mm fraction of Electronic Scrap has been conducted. The results obtained demonstrate that the belted-drum ECS with appropriate design may be applicable for separation of small aluminum particles from Electronic Scrap.
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aluminum recovery from Electronic Scrap by high force eddy current separators
Resources Conservation and Recycling, 1998Co-Authors: Shunli Zhang, Eric Forssberg, Bo R Arvidson, William MossAbstract:The amount of Electronic Scrap which contains a substantial portion of non-ferrous metals, primarily copper and aluminum, has been growing. The present study is directed toward aluminum recovery by a newly developed eddy current separator. The investigation on shredded personal computer and printed circuit board Scrap demonstrates that the High-Force® eddy-current separator will be applicable for this purpose. It has been shown that, by a single pass of the materials on the High-Force® eddy-current separator, an aluminum concentrate out of personal computer Scrap can be obtained with a purity of 85%, while maintaining a recovery in excess of 90%, with the feed rate being up to 0.3 kg/min.
Shunli Zhang - One of the best experts on this subject based on the ideXlab platform.
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Intelligent Liberation and classification of Electronic Scrap
Powder Technology, 1999Co-Authors: Shunli Zhang, Eric ForssbergAbstract:Abstract Mechanical recycling of Electronic Scrap oriented towards overall materials recovery from obsolete Electronics is being implemented worldwide. The main reason is that the amount of Electronic Scrap is increasing and that the content of the precious metals present is decreasing. In this context, an effective liberation of various materials like metals and plastics is a crucial step towards mechanical separation. In addition, classification of Electronic Scrap is also important to be able to provide an appropriate feed material for the subsequent separation process. In the present study, liberation and its impact on the separation of personal computer (PC) Scrap and printed circuit board (PCB) Scrap has been investigated in detail. A special equipment functioning as a shape separator and an aspirator was used for the classification of Electronic Scrap.
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the investigation of separability of particles smaller than 5 mm by eddy current separation technology part i rotating type eddy current separators
Magnetic and Electrical Separation, 1999Co-Authors: Shunli Zhang, Eric ForssbergAbstract:Owing to the growing emergence of the end-of-life electrical and Electronic products with complex material structures and an ever-diminishing particle size of the valuable metals involved, development of eddy current separators (ECS) has been targeting selective separation of small non-ferrous metal particles smaller than 5 mm. Separability of various materials smaller than 5 mm, including fine copper wires, has been investigated using ECS with various design concepts. The present research work is divided into two parts, with Part focusing on the rotating type ECS which are today common in practice, and with Part II dedicated to the ECS with novel concepts such as wet ECS technology. In Part I, three rotating belted-drum ECS were employed, which are manufactured by Bakker Magnetics, the Netherlands, Huron Valley Steel Co., US, and Eriez Magnetics, UK respectively. It is found that the belted-drum ECS are effective for separating materials below 5 mm if the magnetic drum rotates in opposite direction to the conveyor belt. The separation principle, particularly the "backward phenomenon" of the rotating type ECS for small particles has been unravelled in the present study. Moreover, separation of AI from the 010 mm fraction of Electronic Scrap has been conducted. The results obtained demonstrate that the belted-drum ECS with appropriate design may be applicable for separation of small aluminum particles from Electronic Scrap.
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the investigation of separability of particles smaller than 5 mm by eddy current separation technology part i rotating type eddy current separators
Magnetic and Electrical Separation, 1999Co-Authors: Shunli Zhang, Eric ForssbergAbstract:Owing to the growing emergence of the end-of-life electrical and Electronic products with complex material structures and an ever-diminishing particle size of the valuable metals involved, development of eddy current separators (ECS) has been targeting selective separation of small non-ferrous metal particles smaller than 5 mm. Separability of various materials smaller than 5 mm, including fine copper wires, has been investigated using ECS with various design concepts. The present research work is divided into two parts, with Part focusing on the rotating type ECS which are today common in practice, and with Part II dedicated to the ECS with novel concepts such as wet ECS technology. In Part I, three rotating belted-drum ECS were employed, which are manufactured by Bakker Magnetics, the Netherlands, Huron Valley Steel Co., US, and Eriez Magnetics, UK respectively. It is found that the belted-drum ECS are effective for separating materials below 5 mm if the magnetic drum rotates in opposite direction to the conveyor belt. The separation principle, particularly the "backward phenomenon" of the rotating type ECS for small particles has been unravelled in the present study. Moreover, separation of AI from the 010 mm fraction of Electronic Scrap has been conducted. The results obtained demonstrate that the belted-drum ECS with appropriate design may be applicable for separation of small aluminum particles from Electronic Scrap.
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aluminum recovery from Electronic Scrap by high force eddy current separators
Resources Conservation and Recycling, 1998Co-Authors: Shunli Zhang, Eric Forssberg, Bo R Arvidson, William MossAbstract:The amount of Electronic Scrap which contains a substantial portion of non-ferrous metals, primarily copper and aluminum, has been growing. The present study is directed toward aluminum recovery by a newly developed eddy current separator. The investigation on shredded personal computer and printed circuit board Scrap demonstrates that the High-Force® eddy-current separator will be applicable for this purpose. It has been shown that, by a single pass of the materials on the High-Force® eddy-current separator, an aluminum concentrate out of personal computer Scrap can be obtained with a purity of 85%, while maintaining a recovery in excess of 90%, with the feed rate being up to 0.3 kg/min.
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Optimization of electrodynamic separation for metals recovery from Electronic Scrap
Resources Conservation and Recycling, 1998Co-Authors: Shunli Zhang, Eric ForssbergAbstract:The performance of an electrodynamic separator has been optimized in the present study for metals recovery from Electronic Scrap. Eight variables involved in the system was investigated by a 2IV8-4 fractional factorial design in an attempt to determine the significant variables. The effects of those variables were detailed with glass, polyvinyl chloride (PVC) as a representative of plastics, copper wires, copper and aluminum granulates. For various binary mixtures of copper wires and glass or PVC plastic, the electrodynamic separator is able to produce copper products with the grade ranging from 93 to 99%, and recovery from 95 to 99%, respectively, under the optimized conditions. Further, one sample which is a middling fraction resulting from air table separation was also tested. For a single pass, copper and aluminum was upgraded approximately from 11 and 7% to 34 and 22%, while maintaining the corresponding recovery of 87 and 99%, respectively.
Jinki Jeong - One of the best experts on this subject based on the ideXlab platform.
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Removal of chromium(VI) from the leachate of Electronic Scrap using non-ionic Amberlite XAD-7HP resin
Journal of Chemical Technology and Biotechnology, 2013Co-Authors: Nghiem V. Nguyen, Jinki Jeong, Jae Chun LeeAbstract:Background In order to recover the valuable metals from the leach liquor of Electronic Scrap, it is necessary to remove/recover chromium(VI) due to its high toxicity. The non-ionic ion exchange resin, Amberlite XAD-7HP has been employed in the present research to remove Cr(VI) as it possesses large surface area and porosity to adsorb chromium selectively from complex leach solutions in the presence of other ionic species. Results Amberlite XAD-7HP resin effectively adsorbed chromium in the range of acidity from 0.3 to 2.0 mol L−1. The sorption capacity was found to be 16.9 mg Cr g−1 resin in 30 min under the experimental conditions used. Studies carried out with actual leach solution containing Cu, Zn, Ni, Sn, Pb, Au, Cd and Cr showed the selective adsorption of both Cr and Au as they are present in the solution in an anionic form. Cr was then selectively eluted with water/dilute sodium hydroxide from the loaded resin. Subsequently, Au could be eluted with mixed solution of hydrochloric acid and acetone to regenerate the resin for recycle. Conclusion Amberlite XAD-7HP resin is suitable and effective for the removal of Cr(VI) from complex leachate of Electronic Scrap. The other associated metals in the leach solution could be recovered in subsequent steps generating a final solution which could be discharged to the environment.
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Removal of chromium(VI) from the leachate of Electronic Scrap using non‐ionic Amberlite XAD‐7HP resin
Journal of Chemical Technology & Biotechnology, 2012Co-Authors: Nghiem Van Nguyen, Jinki Jeong, Jae Chun LeeAbstract:Background In order to recover the valuable metals from the leach liquor of Electronic Scrap, it is necessary to remove/recover chromium(VI) due to its high toxicity. The non-ionic ion exchange resin, Amberlite XAD-7HP has been employed in the present research to remove Cr(VI) as it possesses large surface area and porosity to adsorb chromium selectively from complex leach solutions in the presence of other ionic species. Results Amberlite XAD-7HP resin effectively adsorbed chromium in the range of acidity from 0.3 to 2.0 mol L−1. The sorption capacity was found to be 16.9 mg Cr g−1 resin in 30 min under the experimental conditions used. Studies carried out with actual leach solution containing Cu, Zn, Ni, Sn, Pb, Au, Cd and Cr showed the selective adsorption of both Cr and Au as they are present in the solution in an anionic form. Cr was then selectively eluted with water/dilute sodium hydroxide from the loaded resin. Subsequently, Au could be eluted with mixed solution of hydrochloric acid and acetone to regenerate the resin for recycle. Conclusion Amberlite XAD-7HP resin is suitable and effective for the removal of Cr(VI) from complex leachate of Electronic Scrap. The other associated metals in the leach solution could be recovered in subsequent steps generating a final solution which could be discharged to the environment.
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Recovery of Cu and Sn from waste electrical and Electronic Scrap utilizing waste copper slag
Journal of Metallurgy and Materials Science, 2009Co-Authors: Byung-su Kim, Jinki Jeong, Jae Chun Lee, Seongwon Kang, Kwang Ho Lee, Nag-joon ChoiAbstract:Large amounts of waste electrical and Electronic Scrap containing considerable valuable metals such as copper, tin, gold, and silver is generated in Korea. In the view of resource recycling and to protect the environment it is necessary to recover the valuable metals from waste electric and Electronic Scrap. Present work reports a novel pyrometallurgical process for the recovery of copper and tin from the waste electrical and Electronic Scrap (WEES) by utilizing the waste copper slag as a slag formative. In each set of experiment, waste electric and Electronic Scrap were melted with waste copper slag for 30 min at 1573 K after adding suitable amount of CaO as an additional slag formative. Based on proposed process flow-sheet, >90% of copper and >80% of tin were recovered as Cu-Fe-Sn alloy from waste electric and Electronic Scrap.
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recovery of cu and sn from the bioleaching solution of Electronic Scrap
Journal of the Korean Institute of Resources Recycling, 2006Co-Authors: Jae-woo Ahn, Jinki Jeong, Meongwoon Kim, Jae Chun LeeAbstract:A study for recovering of copper and lead from Electronic Scraps has been carried out using a combination of bioleaching and solvent extraction. It was found that the citric acid generated by Aspergillus niger could be an imporant leaching agent acting in the solubilization of copper, iron, lead and tin from the Electronic Scrap. Copper could be selectively extracted by 10% LIX84 from the leaching solution and it recoved 99.9% of metallic copper by electrowinning process. Tin and iron were extracted from the remaining solution by 10% Alamine336 and stripped by NaCl solution. Finally, tin could be recovered as a metallic precipitates from the mixed solution of tin and iron by cementation with iron powder.
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Bioleaching of Electronic Scrap using Thiobacillus ferrooxidans
Geosystem Engineering, 2005Co-Authors: Jae-woo Ahn, Jinki Jeong, Jae Chun Lee, Dong-gin Kim, Jong-gwan AhnAbstract:ABSTRACT In order to recover valuable metals from a waste Electronic Scrap, we investigated the bioleaching of Cu, Zn, Al, Co, Ni, Sn and Pb using Thiobacillus ferrooxidans as leaching microorganism in a shaking flask. In a preliminary study, in order to obtain the data on the leaching of Cu, Zn, Al, Co and Ni, the metal leaching behaviors were accomplished using metal powders instead of Electronic Scrap. As the increase of metal powder concentration in solution, the leaching percentages of Cu, Zn, Co, Al, Ni powders were reduced. At the metal concentrations of 1.0 and 5.0g/L, more than 85% of Cu, Co and Zn powders were leached out. At the Electronic Scrap concentration of 100g/L, Thiobacillus ferrooxidans were able to leach more than 90% of the available Cu, Co. But Al, Zn and Ni were able to leach less than 40%. No Pb and Sn were detected in the leachate. Pb was precipitated as PbSO4, whereas Sn precipitated probably as SnO.
William Moss - One of the best experts on this subject based on the ideXlab platform.
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aluminum recovery from Electronic Scrap by high force eddy current separators
Resources Conservation and Recycling, 1998Co-Authors: Shunli Zhang, Eric Forssberg, Bo R Arvidson, William MossAbstract:The amount of Electronic Scrap which contains a substantial portion of non-ferrous metals, primarily copper and aluminum, has been growing. The present study is directed toward aluminum recovery by a newly developed eddy current separator. The investigation on shredded personal computer and printed circuit board Scrap demonstrates that the High-Force® eddy-current separator will be applicable for this purpose. It has been shown that, by a single pass of the materials on the High-Force® eddy-current separator, an aluminum concentrate out of personal computer Scrap can be obtained with a purity of 85%, while maintaining a recovery in excess of 90%, with the feed rate being up to 0.3 kg/min.