The Experts below are selected from a list of 1611 Experts worldwide ranked by ideXlab platform
Jiakuan Yang - One of the best experts on this subject based on the ideXlab platform.
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a closed loop ammonium salt system for recovery of high purity lead tetroxide product from spent lead acid battery paste
Journal of Cleaner Production, 2020Co-Authors: Jiakuan Yang, Sha Liang, Junxiong Wang, Peiyuan Zhang, Keke Xiao, Huijie Hou, Bingchuan LiuAbstract:Abstract Hydrometallurgical Process for recovery of spent lead-acid battery paste shows great advantages in reducing SO2 and lead particulates emissions than traditional Pyrometallurgical Process. However, the hydrometallurgical Process usually has drawbacks of high consumption of chemical reagents and difficulty in removing impurities (especially Fe and Ba elements) from the recovered product. In this paper, a closed-loop ammonium salt system is proposed for spent lead-acid battery paste recovery. Both recirculation of leaching reagents and preparation of low-impurity recovered products have been realized. The spent lead paste is first leached by a mixed solution of ammonium acetate, acetic acid and hydrogen peroxide. After filtration, the separated lead acetate solution is reacted with ammonium carbonate to generate lead carbonate via precipitation Process. The impurity elements are efficiently removed by pH control and complexation between acetate ions and impurity elements in the leaching and precipitation Processes. The soluble SO42− separated from the precipitation Process is removed by adding barium acetate to generate solid BaSO4 by-product. At the same time, the regenerated ammonium acetate filtrate is separated and re-used in the next-round leaching Process in order to realize a closed-loop Process. In the 5th round of filtrate recirculation Processes, the leaching ratio of lead is maintained at levels higher than 92.7 wt%. Furthermore, high-purity lead tetroxide is prepared by calcination of lead carbonate in air at 450 °C. The contents of Fe and Ba in the final recovered lead tetroxide product are as low as 2.7 and 5.2 mg/kg, respectively. The recovered lead tetroxide product meets the specifications for use as an additive in the positive active materials for making a new lead-acid battery. This study provides a feasible technology for high-value utilization of spent lead paste.
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ethylene glycol mediated synthesis of pbo nanocrystal from pbso4 a major component of lead paste in spent lead acid battery
Materials Chemistry and Physics, 2011Co-Authors: Jiakuan Yang, Vasant R KumarAbstract:Abstract Lead sulfate (PbSO 4 ) is a major component of lead paste of spent lead acid batteries, normally over 60%. In traditional Pyrometallurgical Process, the decomposition of PbSO 4 requires a relatively high temperature and the use of coal as both the reducing agent and as the source of thermal energy, thereby causing emissions of SO x , lead particles and CO 2 . In this study, lead sulfate was desulfated by adding an aqueous solution comprising citric acid and tri-sodium citrate with the modulation of ethylene glycol (EG) in order to control the morphology. The treating agent reacted with lead sulfate to form an aqueous solution of sodium sulfate and a precipitated precursor of lead carboxylate crystals. The precursor was characterized by XRD, SEM, SDT and FTIR. The morphology of the EG-mediated precursor showed a regular columnar shape. On calcining at relatively low temperatures, EG-mediated precursor was transformed into fine particles of lead oxide. The characteristics of calcined products were investigated by XRD, SEM, and TEM. The results showed that nanostructured crystals of lead oxide could be easily prepared by combustion of EG-mediated precursor at 350 °C with a lead recovery of about 98%. This paper has paved the way for obtaining nanostructured PbO from waste battery scrap.
Giuseppe Micali - One of the best experts on this subject based on the ideXlab platform.
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An Eco-balance of a Recycling Plant for Spent Lead–Acid Batteries
Environmental Management, 2005Co-Authors: Roberta Salomone, Fabio Mondello, Francesco Lanuzza, Giuseppe MicaliAbstract:This study applies Life Cycle Assessment (LCA) methodology to present an eco-balance of a recycling plant that treats spent lead–acid batteries. The recycling plant uses Pyrometallurgical treatment to obtain lead from spent batteries. The application of LCA methodology (ISO 14040 series) enabled us to assess the potential environmental impacts arising from the recycling plant’s operations. Thus, net emissions of greenhouse gases as well as other major environmental consequences were examined and hot spots inside the recycling plant were identified. A sensitivity analysis was also performed on certain variables to evaluate their effect on the LCA study. The LCA of a recycling plant for spent lead–acid batteries presented shows that this methodology allows all of the major environmental consequences associated with lead recycling using the Pyrometallurgical Process to be examined. The study highlights areas in which environmental improvements are easily achievable by a business, providing a basis for suggestions to minimize the environmental impact of its production phases, improving Process and company performance in environmental terms.
Jae Chun Lee - One of the best experts on this subject based on the ideXlab platform.
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Reclamation of tungsten from carbide scraps and spent materials
Journal of Materials Science, 2019Co-Authors: Rajiv Ranjan Srivastava, Mooki Bae, Jae Chun Lee, Vinay KumarAbstract:This paper reviews the state-of-the-art recycling of tungsten from carbide (WC) scraps and other spent alloys generated by various production and application industries. With an aim of direct reuse or chemical recovery of tungsten, the reclamation of WC is commonly divided into three parts: (1) pyrometallurgy, (2) hydrometallurgy, and (3) a combined (pyro + hydro) metallurgical Process. The Pyrometallurgical Process consists of a thermal treatment under an oxidizing, reducing, or carburizing condition and of breaking the structure of hardmetals by dissolving the binder metal in a molten bath to obtain WC from spent/scrap materials. The hydrometallurgical Process, based on leaching in acid and/or alkali solutions, follows precipitation/solvent extraction/ion exchange/crystallization operations to concentrate and recover the salt/s of tungsten and associated metals. The combination of both Processes is employed mainly to convert the carbide phase of WC (along with the binder and/or additive metals) to their oxide forms prior to leaching in the acid/alkali solution to enhance the extraction efficacy in the aqueous solution. A critical analysis with respect to the Processing conditions for extracting tungsten with the binder metal cobalt from various scrap/spent materials is given. The present paper will be helpful in developing an overall understanding of tungsten reclamation from the WC and other alloys that can provide future research directions to obtain the sustainability of this strategically conflict element.
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current status of Pyrometallurgical Process for the reclamation of urban ore
Journal of the Korean Institute of Resources Recycling, 2012Co-Authors: Byung-su Kim, Jae Chun Lee, Doyeoun Shin, Jinki Jeoung, Kangin Rhee, Jeongsoo Sohn, Donghyo Yang, Minseuk Kim, Sookyung KimAbstract:In the points of the environmental conservation and the recirculating utilization of limited resources, it is very important to recover valuable metals like Au, Ag, Pd, Cu, Sn, Ni, Co, and Li used as industrial raw materials from urban ores. From now, many Processes have been developed for recovering the valuable metals contained in urban ores and some of them have been operated commercially. In the paper, Pyrometallurgical Processes developed for reclaiming valuable metals from urban ores will be briefly introduced.
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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.
Huayi Yin - One of the best experts on this subject based on the ideXlab platform.
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recovery and regeneration of lithium cobalt oxide from spent lithium ion batteries through a low temperature ammonium sulfate roasting approach
Journal of Power Sources, 2020Co-Authors: Yiqi Tang, Beilei Zhang, Hongwei Xie, Pengfei Xing, Huayi YinAbstract:Abstract The operating temperature determines the energy consumption and lithium extraction rate of a Pyrometallurgical Process. This paper aims to employ a molten ammonium sulfate ((NH4)2SO4) assisted roasting approach to recovering and regenerating LiCoO2 from spent lithium-ion batteries (LIBs) at 400 °C. First, cathode materials from the spent LIBs are converted to CoSO4 and Li2SO4 via a sulfation roasting approach. Both recovery rates of Li and Co reach over 98% at 400 °C for 2h and at an (NH4)2SO4/(cathode materials) mass ratio of 4:1 in Ar atmosphere. Then, the obtained Co(OH)2 and Li2CO3 are used to regenerate LiCoO2 that delivers a specific capacity of over 154 mAh g−1 at 1C with capacity retention of 94% after 100 cycles. Overall, the molten (NH4)2SO4 assisted roasting approach reduces the operating temperature to 400 °C while maintaining a high extraction rate of over 98% for both Li and Co, promising an energy-efficient approach to recovering various cathode materials from spent LIBs.
Il Sohn - One of the best experts on this subject based on the ideXlab platform.
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fundamental thermokinetic study of a sustainable lithium ion battery Pyrometallurgical recycling Process
Resources Conservation and Recycling, 2020Co-Authors: Ohsung Kwon, Il SohnAbstract:Abstract With increased global consumption of Lithium-ion batteries (LIBs), a sustainable recycling Process is necessary to reduce wastes and retrieve highly-valued elements. But to achieve an optimized sustainable recycling Process, a fundamental understanding of the thermokinetic reactions during Pyrometallurgical LIB recycling is essential. In this work, the thermodynamics and kinetics of high-temperature reactions for LIBs during Pyrometallurgical recycling are studied using a thermo-gravimetric analyzer (TGA) equipped with a gas mass spectrometer. Cylindrical composite pellets comprised of cathode and anode active materials were heated from room temperature (RT) to 1500 °C at a constant heating rate of 20 °C/min. By comparing the measurements of the mass loss and simultaneous gas evolution, the anticipated theoretical thermodynamic reactions are confirmed and determined, which is fundamental to the development of a sustainable Pyrometallurgical Process to recover valuable metals in LIBs. Isothermal reductions from 850 to 1000 °C indicated reactions to be temperature sensitive and mass transfer to be comparatively fast. Using various kinetics models, the uniform internal reduction mechanism was found to be dominant.
