Method for recovering metals from waste CPUs (central processing units)

Abstract

The invention relates to a method for recovering metals from waste CPUs (central processing units), which comprises the following steps: pulverizing waste CPUs, adding the pulverized powder into a nitric acid solution, and filtering to obtain a filtrate and a filter residue; adding the filter residue into aqua regia, filtering to obtain a leaching solution, and adding sodium metabisulfite into the leaching solution to obtain a gold precipitate; meanwhile, adding sodium chloride into the filtrate, filtering to obtain a new filtrate and a silver chloride precipitate; adding sodium hydroxide into the new filtrate to obtain a cupric hydroxide precipitate; uniformly mixing the silver chloride precipitate with anhydrous sodium carbonate, roasting, pulverizing the roasted reaction product, adding into hot water, stirring, and filtering to obtain a silver precipitate; and respectively smelting the gold precipitate, silver precipitate and cupric hydroxide precipitate to obtain metals gold, silver and copper. The invention achieves the goal of recovering noble metals from waste CPUs at high efficiency, low pollution and low cost, and achieves the effect of maximally recovering noble metals gold, silver and copper.

Description

technical field [0001] The invention relates to the technical field of recycling electronic products, in particular to a metal recycling method for waste CPUs. Background technique [0002] Along with the popularization and wide application of computers, the number of scrapped computers is increasing every year. Among them, although the used central processing unit (CPU) has low performance and is difficult to be reused, it contains precious metals such as gold, silver, and copper, and has a very high recycling value. Gold has extremely high corrosion resistance and stability, as well as good electrical and thermal conductivity, and is widely used in international reserves, jewelry decoration, industry and science and technology; silver has good ductility, electrical conductivity and heat transfer, Widely used in thermal and electrical conductors, mirrors and photosensitive materials; palladium is a relatively active metal among precious metals, widely used in the synthesis...

AI Technical Summary

Problems solved by technology

[0003] At present, the technology of recycling precious metals from low-content precious metal wastes at home and abroad is still immature, and is still in the research stage. A simple and efficient recycling method; and the government’s investment in this area is relatively small. With the increase of waste containing precious metals year by year, the government and society are paying more and more attention to the recycling of waste materials and the elimination of environmental pollution. Therefore, from precious metals Recycling precious metals from waste has significant economic and social benefits

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