Comprehensive recovery method for valuable metal in copper-cadmium slag

Abstract

The invention discloses a comprehensive recovery method for valuable metal in copper-cadmium slag. The copper-cadmium slag serves as a raw material, Cu, Zn, Cd, Ni and Co in the slag are efficiently recycled through an all-wet technology of oxygen pressure sulfuric acid leaching and sequential extraction, metal covered with the copper-cadmium slag is fully exposed in acid through a pressurized high-temperature oxidation effect, the acid leaching process is reinforced, reasonable process steps and process parameters are adjusted, tendency distribution of all metal is controlled, the influences of Ni, Co, Fe and other elements in the slag on separation and extraction of Cu, Zn and Cd are avoided, and the metal leaching rate and recovery rate are increased. Meanwhile, waste liquid generated in the whole process course serves as a leaching agent to return to carry out leaching, so that environmental pollution is avoided. Compared with the prior art, the process flow is shortened, the leaching time is shortened, the leaching cost is reduced, the energy consumption in the whole process course is reduced, and the beneficial effects of high efficiency, environmental friendliness and low cost are achieved.

Description

Technical field [0001] The invention relates to a method for recovering valuable metals, in particular to a method for comprehensively recovering valuable metals in copper-cadmium slag. Background technique [0002] Copper cadmium slag is a large amount of waste slag produced by the removal of copper and cadmium in the zinc wet production purification system. Every 10,000 tons of electro-zinc produced approximately 1,300 tons of copper cadmium slag. This type of slag generally contains more than 0.5% Cu, more than 2% Cd, more than 0.2% Ni, more than 0.03% Co, and more than 40% Zn, which has a very high comprehensive recycling value. There are two main processes for recovering valuable metals from copper and cadmium slag, namely, fire process and wet process. The pyrotechnical process is mature, but the energy consumption is relatively high, and higher-priced coking coal is required, and equipment for recovering ash and purifying gas is required to process the flue gas, so the in...

AI Technical Summary

Problems solved by technology

This process only improves and perfects the traditional process, adding the extraction and separation technology of Cu, without considering the influence of other impurities or residual oxidants in the copper cadmium slag leaching solution on the extraction and separation, while still using high and low temperature zinc for Co, Ni, and Cd. Therefore, the separation of Co, Ni, and Cd is still not complete, and it is easy to cause a large amount of metal loss during the replacement process, and the recovery rate of Cu, Zn, Cd, Co, and Ni is still not high.

It was studied by adding KMnO 4 or MnO 2 , NaClO, KClO 3 and other oxidants for oxidative acid leaching, and then extract Cu, Zn, Cd, Co, and Ni step by step from the acid leaching solution. Although good results can be achieved, new Mn-containing 2+ , Mn 4+ or Cl - The impurity ions have a great influence on the subsequent extraction of Cu and Zn.

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