Abstract: In order to rationally utilize low grade copper ore and its waste resource, leaching test and reaction thermodynamic analysis were made of the enhancement of the dump leaching of chalcopyrite by pyrite. The results show the solution potential range required by pyrite reaction covers that for chalcopyrite leaching enhancement by Fe³⁺ and it is feasible to promote the leaching of chalcopyrite by pyrite under anoxic condition; the participation of pyrite can accelerate the reduction of the concentration ratio of Fe³⁺ to Fe²⁺, and hence the reduction of the potential so as to promote the leaching of chalcopyrite; the upper leaching solution is taken as the initial solution for the promotion of chalcopyrite leaching by pyrite at the dump depth where it is anoxic, with Fe³⁺, Cu²⁺, Fe²⁺ in the upper solution as the prerequisite for pyrite's promotion behavior.

Key words: Chalcopyrite, Pyrite, Dump site, Thermodynamics, Leaching, Ferrous ions, Redox potential