高磷高钼复杂白钨矿的脱磷-除钼处理工艺

利用磷灰石、钼酸钙和钨酸钙等含钙矿物与盐酸反应的差异性规律，首先在温和的盐酸浸出条件下预处理高磷高钼复杂白钨矿，即反应温度为50 ℃，盐酸浓度2.5 mol/L，反应时间2 h，液固比（指液体体积与固体质量之比，单位为L/kg，下同）5:1的条件下实现杂质磷的高效选择性浸出，磷的浸出率达到99%以上，同时实现钨钼的初步分离，钼浸出率为44.76%，钨浸出率仅为1.84%。然后，再利用钨酸和钼酸在盐酸体系中溶解度的性质差异，进一步提高盐酸浓度和反应温度强化浸出，在盐酸浓度4 mol/L，反应温度80 ℃，反应时间2 h，液固比5:1的条件下，钼的浸出率达到95%，而钨以钨酸的形式留在固相，此步骤的钨浸出率只有1.55%，实现了钼的深度分离和钨矿的转型。 

Process of removing phosphorus and molybdenum from complex scheelite concentrates with high phosphorus and molybdenum

Considering the differences of hydrochloric acid leaching fluorapatite, calcium molybdate and scheelite concentrate, the scheelite concentrates which contain high phosphorus and molybdenum were first treated by hydrochloric acid, under the conditions such as hydrochloric acid concentration 2.5 mol/L, reaction temperature 50 ℃, reaction time 2 h, liquid-solid ratio of 5:1. The results showed that over 99% of phosphorus was leached, molybdenum leaching rate was 44.76%, and the tungsten loss rate was only 1.84%. After that, based on the different solubility of tungstic acid and molybdic acid in hydrochloric acid, the scheelite concentrates were leached by hydrochloric acid. Under the conditions of hydrochloric acid concentration 4 mol/L, reaction temperature 80 ℃, reaction time 2 h and liquid-solid ratio of 5:1, the leaching rate of molybdenum reached 95%, and tungsten was leached in the form of tungstate in solid phase. Hence the loss rate of tungsten was only 1.55%, which realized the deep separation of molybdenum and tungsten.