Method for reclaiming silver and copper in silver-copper alloy scrap

Abstract

The invention provides a method for recycling silver and copper in silver and copper alloy scrap, relating to a method for the wet recycling of the silver and copper in the silver and copper alloy scrap. The method is characterized in that the recycling process comprises the steps that the silver and copper alloy is firstly dissolved by using nitric acid, the solution is heated, evaporated and condensed to obtain silver nitrate and copper nitrate crystal; heating is continued to obtain a copper oxide mixture with decomposed silver nitrate and copper nitrate, water is slowly added into the mixture to cause the silver nitrate in the mixture to be dissolved, solid copper oxide and silver nitrate solution are separated out by filtration, and finally, a silver nitrate solution electro-deposition tank is added to directly carry out electro-deposition to prepare electro-deposited silver. Compared with the traditional method, the method of the invention eliminates the processes of chloridized silver deposition and copper separation, and hydrazine hydrate reduction silver-preparation, thus effectively reducing the reagent consumption and the silver-recycling cost. Acid-containing solution generated in the electro-deposition process can be circularly used for silver and copper alloy dissolving without emission. The method of the invention can separate and recycle silver and copper, with high efficiency, low cost and simplicity, and has high electro-deposited silver quality.

Description

technical field [0001] The invention discloses a method for recovering silver and copper in silver-copper alloy waste, relating to a method for recovering silver and copper from silver-copper alloy waste by wet method. Background technique [0002] Silver has the highest electrical conductivity and thermal conductivity among metals, and it is mainly used in industry, jewelry, currency making, and medical use. Its industrial usage accounts for 86%, electrical contacts and solder usage account for 25%, and silver-copper is its main component. The silver-copper alloy waste in the production process must be recycled. [0003] Commonly used wet recovery processes are nitric acid dissolution of alloys, precipitation of silver chloride to separate copper, and reduction of hydrazine hydrate to prepare sponge silver. This process is longer, consumes reagents such as hydrochloric acid, ammoniacal liquor, hydrazine hydrate, and the cost is high, the quality of silver powder is 99.95%...

AI Technical Summary

Problems solved by technology

The process is long, consumes hydrochloric acid, ammonia water, hydrazine hydrate and other reagents, and the cost is high. The quality of silver powder is 99.95%, the recovery rate of silver is low, and the copper is not recovered.