A New Process for Molybdenum-Tungsten Extraction from High Pressure Leaching Solution of Crude Molybdenum-Tungsten Oxide Concentrate

A new process of molybdenum-tungsten extraction from high pressure leaching solution of crude molybdenum-tungsten oxide concentrate was studied,including the steps of solution pre-treatment,molybdenum-tungsten precipitation,solid-liquid separation,product drying and so on.When the high pressure leaching solution contains 27.26 g/L Mo and 5.70 g/L WO3,Mo and WO3 precipitation rates are 99.94% and 85.08%,respectively,under the conditions of pH value of 7～8,precipitation time of 1～1.5 h,reaction temperature of 80 ℃,and CaCl2 dosage of 2.15 times the theoretical value,and the calcium molybdate-tungstate product contains 36.08% Mo and 7.11% WO3,with impurity of 0.012% P and 0.004 5% As.The new process has simple flowsheet,good operability and high molybdenum-tungsten recovery.