| Germanium (Ge) is a rare metal which has strategic significance and also important semiconductor material. While copper(Cu) and lead(Pb) are also important metal elements in the economic development. Cu-Pb slag with germanium-rich containing many important valuable elements. it was treated with unsuitable way and reused with low ratio, which brought out the problems of resource waste and environment pollution. In the condition of economic rapidly developing and metal resource decreaseing, recovery of valuable metals especially rare metal should be put on the agenda.The paper takes Cu-Pb slag with germanium-rich as research object, and the experiments of its leaching toxicity were carried out with different extraction solvents, the results showed that Cu-Pb slag with germanium-rich was hazardous waste with strong leaching toxicity. The strongest leaching toxicity behaved by using the acetic acid method, the next was by using the nitrate-sulfate mixed acid method, the smallest was by using the ionized water method.Through leaching dynamics analysis of Ge and Cu in the sulfur acid, Ge and Cu leaching process were controlled by chemical reaction. Leaching process can be expressed by dense spherical particle model, and the equation is 1-(1-α) 1/3=Kt. The apparent activation energy of Ge and Cu in the study were respectively 42.77kJ/mol and 43.14kJ/mol.Through the orthogonal experiments, the order of all the factors on Ge leaching ratio was pH>leaching temperature>leaching time>stirring speed>the liquid-solid ratio,and the order on Cu leaching ratio was pH>leaching temperature>the liquid-solid ratio >stirring speed>leaching time.The optimal condition of sulfur acid leaching Cu-Pb slag with germanium-rich were as follows:the liquid-solid ratio was 10, pH equaled tol, stirring speed was 400r/min, leaching temperature was 75℃, sample size was 200 mesh, and the leaching rate of Ge and Cu could respectively reach up to 91% and 95%.
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