Recycling of waste electrical and electronic equipment has become an urgent global issue in recent years from the prospectives of resources recycling and environmental protection.In the present work,the recycling of w...Recycling of waste electrical and electronic equipment has become an urgent global issue in recent years from the prospectives of resources recycling and environmental protection.In the present work,the recycling of waste memory modules(WMMs)through low-temperature alkali melts was investigated,based on the thermodynamic analysis of the nonmetallic reactions of brominated epoxy resin,glass fiber and memory chip with the molten mixed alkali.The effects of the reaction temperature and the ratio of alkali mixture on the removal rate of nonmetallic parts in WMMs were discussed under the condition of air atmosphere.The optimum process parameters were further confirmed by in-situ monitoring of the temperature during the whole reaction process.The mixtures with Cu,Fe and Ni as the main components were obtained after the treatment of WMMs in the molten alkali.These mixed metals were further separated into copper-rich and ferronickel-rich metals by physical magnetic separation.Moreover,the precious metals Au and Ag were enriched in Cu-rich alloys.This work provided an efficient and environment-friendly method for metal recycling from WMMs.展开更多
A sustainable materials management for metals should be achieved to conserve resources of metal minerals.For the sustainable materials management,material flows through the whole life cycle of materials have been reco...A sustainable materials management for metals should be achieved to conserve resources of metal minerals.For the sustainable materials management,material flows through the whole life cycle of materials have been recognized by material flow analysis(MFA) studies.Former MFA studies pointed out that cyclic use of metals could be enhanced not only by increasing quantity of recovered scrap but also by upgrading quality of the scrap.In general,the quality is degraded by contaminants which commingle at disassembling processes.The mixture of contaminants depends on usage of materials in products.Here,Type I ecolabelling has a potential to convey messages for avoiding mixture of contaminants to the producers of finished products.In this study,on the basis of a survey on existing certification criteria related to metals in the world,a general concept of certification criteria on sustainable materials management for metals in Type I ecolabelling system is proposed.Finally,we propose six criteria in the form of certification criteria in Type I ecolabelling system.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.51974288,51574216,51774264 and 51901231)the Liaoning Provincial Department of Education(Grant No.JYT19063)+1 种基金the Natural Science Foundation of Liaoning Province of China(Grant No.2019-MS-332)the Key Project of Innovation Foundation of IMR-CAS(Grant No.SCJJ-2013-ZD-03).
文摘Recycling of waste electrical and electronic equipment has become an urgent global issue in recent years from the prospectives of resources recycling and environmental protection.In the present work,the recycling of waste memory modules(WMMs)through low-temperature alkali melts was investigated,based on the thermodynamic analysis of the nonmetallic reactions of brominated epoxy resin,glass fiber and memory chip with the molten mixed alkali.The effects of the reaction temperature and the ratio of alkali mixture on the removal rate of nonmetallic parts in WMMs were discussed under the condition of air atmosphere.The optimum process parameters were further confirmed by in-situ monitoring of the temperature during the whole reaction process.The mixtures with Cu,Fe and Ni as the main components were obtained after the treatment of WMMs in the molten alkali.These mixed metals were further separated into copper-rich and ferronickel-rich metals by physical magnetic separation.Moreover,the precious metals Au and Ag were enriched in Cu-rich alloys.This work provided an efficient and environment-friendly method for metal recycling from WMMs.
基金the Grant-in-Aid for Young Scientists (A) KAKENHI 22686084
文摘A sustainable materials management for metals should be achieved to conserve resources of metal minerals.For the sustainable materials management,material flows through the whole life cycle of materials have been recognized by material flow analysis(MFA) studies.Former MFA studies pointed out that cyclic use of metals could be enhanced not only by increasing quantity of recovered scrap but also by upgrading quality of the scrap.In general,the quality is degraded by contaminants which commingle at disassembling processes.The mixture of contaminants depends on usage of materials in products.Here,Type I ecolabelling has a potential to convey messages for avoiding mixture of contaminants to the producers of finished products.In this study,on the basis of a survey on existing certification criteria related to metals in the world,a general concept of certification criteria on sustainable materials management for metals in Type I ecolabelling system is proposed.Finally,we propose six criteria in the form of certification criteria in Type I ecolabelling system.
