Separation and Recovery of Valuable Metals from Automobile Shredder Residue (ASR) Fly Ash by Wet Processing

The amount of automobile shredder residue (ASR) reaches 0.6-0.7 million tons per year in Japan, approximately. One of the effective processes to reduce the amount of ASR was the incineration process, generally carried out in smelting and refining plant. During the process, however, large amounts of ASR fly ash containing chloride (C1) compounds and some valuable metals (e.g. copper, zinc) were produced. In this contribution, the recycling of copper, zinc and C sub(a)/N sub(a) chloride compounds from ASR fly ash was investigated by using a process consisting of cementation, sulfide precipitation and distillation. The experimental results showed that high-grade copper (metal and oxide) and zinc (sulfide) were separated with recovery rate >97% from the HC1 washing solution of ASR fly ash by cementation and precipitation. C sub(a)Cl sub(2).9H sub(2)0 and NaCl were obtained from the washing solution of ASR fly ash by vacuum distillation.