The surface features of fluorapatite (FA, Ca₅(PO₄)₃F) and dolomite (CaMg(CO₃)₂) conditioned with sulfuric acid (H₂SO₄) were examined through flotation experiments, contact angle tests, time-of-flight secondary ion mass spectrometry (TOF-SIMS), and FTIR experiments. The flotation and contact angle results suggested that oleate insufficiently adsorbed onto the H₂SO₄-treated FA surface such that the FA surface remained hydrophilic. However, using oleate as a collector, the recovery and hydrophobicity of H₂SO₄-treated dolomite were satisfactory. TOF-SIMS and FTIR studies indicated that sulfate anion bound with Ca atoms on the FA surface, which hindered oleate adsorption onto the FA surface. Meanwhile, sulfate anion and oleate species appeared on the dolomite surface, thereby generating a hydrophobic dolomite and also a satisfactory recovery.

Leaching test on the oxidized zinc ore from Kashi, Xinjiang Autonomous Region is studied in the (NH₄)₂SO₄-NH₃-H₂O system; Systematic studies are made to show the effects of various factors on the leaching rate of zinc. The optimum conditions for leaching is finally confirmed, i.e., the grinding fineness is 80% -74um, concentration of ammonium sulfate is 2mol/L, concentration of ammonia is 4mol/L, reaction temperature is 40°C, the ratio of liquid to solid is 4: 1; stirring rate is 300rpm and leaching time is 3h. Ultimately, the leaching rate of Zn could reach more than 91%.

Leaching test on the oxidized zinc ore from Kashi, Xinjiang Autonomous Region is studied in the (NH 4) 2 SO 4-NH 3-H 2 O system; Systematic studies are made to show the effects of various factors on the leaching rate of zinc. The optimum conditions for leaching is finally confirmed, i.e., the grinding fineness is 80%-74um, concentration of ammonium sulfate is 2mol/L, concentration of ammonia is 4mol/L, reaction temperature is 40˚C, the ratio of liquid to solid is 4:1; stirring rate is 300rpm and leaching time is 3h. Ultimately, the leaching rate of Zn could reach more than 91%.