Coupling leaching of sphalerite concentrate

Studies on coupling process of sphalerite concentrate leaching in H2SO4–HNO3 and tetrachloroethylene extracting of sulfur were reported. Mechanism of coupling leaching and effects of adding amounts of C2Cl4, temperature and liquid-to-solid ratio on leaching process were investigated separately. The results indicated that the zinc recovery was up to 99.6% after 3 h of leaching at 85 °C, 0.1 MPa O2, with 20 g sphalerite concentrate in 200 ml leaching solution of 2.0 mol/l H2SO4 and 0.2 mol/l HNO3, in the presence of 10 ml C2Cl4. The leaching time was 50% shorter than the common leaching. The coupling effect was distinct.