Recovery of gallium from zinc concentrate by pressure oxygen leaching

Zinc concentrate with high gallium content is one of the main resources of gallium. The gallium presents in the form of isomorphism in tetrahedron coordination with sulfur in sphalerite. The research was to investigate the amenability of zinc concentrate with high gallium to pressure oxygen leaching. The particle size, sulfuric acid concentration, oxygen partial pressure, additive amount, and time of reaction were studied. The extraction yields of gallium and zinc are 86 % and 98 %, respectively. The optimal condition is 100 g of zinc concentrate with particle size smaller than 38 μm, sulfuric acid concentration 150 g·L−1, leaching temperature 150 °C, leaching time 120 min, oxygen partial pressure 0.7 MPa, additive amount of 0.2 wt%.