Method for recovering noble metal from waste titanium anodes with noble metal coatings

Abstract

The invention provides a method for recovering noble metal from waste titanium anodes with noble metal coatings, and belongs to the technical field of metal sorting. After a stripping agent is heated, the waste titanium anodes, with the noble metal coatings, to be treated are immersed into the stripping agent to be soaked for several minutes so that the noble metal coatings can be stripped into the stripping agent, and then the remaining titanium anodes are taken out; in this way, the stripping agent is repeatedly used, solid-liquid separation is performed on the stripping agent to obtain filter residues and filter liquid, and a common noble metal separation and purification technology is performed on the filter residues, so that the pure noble metal is obtained; a common titanium recovery technology is performed on the filter liquid to recover titanium. The stripping recovery rate of the noble metal and the titanium-base anodes reaches up to 99%, and the purity of the noble metal can be larger than or equal to 99.95%; the loss of the titanium-base anodes is low and is smaller than or equal to 0.5%. The method is wide in application range and short in technology period, the maximum recovery rate of the noble metal is larger than or equal to 98%, and because the titanium-base anodes after the noble metal is stripped can be reused through repairing, the production cost is lowered. According to the method, operation is easy, heating temperature is low, no caking exists in a system, consumption of raw materials is low, no acid mist is generated, and the effects of energy saving and environmental friendliness are achieved.

Description

technical field [0001] The invention relates to a method for recovering precious metals from waste titanium anodes with precious metal coatings, and belongs to the technical field of metal sorting. Background technique [0002] The caustic soda and chlor-alkali industry is a relatively old electrolytic industry. Its requirements for electrode materials have promoted the rapid development of anode materials. The patent for platinum plating on lead in 1901; the patent for platinum plating on graphite in 1909; Bill published an article on titanium-based coating titanium-precious metal film; in 1957, Olin Company of the United States began laboratory research for industrial production purposes, and cooperated with ICI Company in 1960 to apply its research results to mercury electrolyzers; in 1965, Bill Achieved RUO 2 Patent rights for coated titanium anodes; Bill's RUO in 1968 2 -TiO 2 Coating research results have been industrialized in the chlor-alkali plant of DeNom Compan...

AI Technical Summary

Problems solved by technology

[0018] (1) The stripping recovery rate is low, and the general stripping recovery rate is only 80-90%;

[0019] (2) The loss of titanium during stripping in the titanium anode is large, generally > 3%

Due to the high titanium content in the stripping, it will increase the difficulty of separating and purifying precious metals from the stripping, and it is not conducive to the re-plating and regeneration of titanium anodes;

[0020] (3) When stripping, add NaOH and NaNO 3 or use NH 4 HSO 4 , using the high-temperature molten salt method, the waste gas produced affects the environment, using the hydrochloric acid boiling method or sulfuric acid boiling method, the acid mist will affect the surrounding environment, and the operating personnel's production environment is harsh, affecting their health

[0021] (4) The sulfuric acid electrolysis method has high production costs, large investment, long production cycle, and incomplete stripping of precious metals and titanium

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