The coarse ammonium molybdate solution containing Mo 96.8 g/L and As 8.75 g/L was obtained by extracting Mo with N235 from leaching solution of Ni-Mo ore. Arsenic was removed as MgNH4AsO4 after adding magnesium chloride into the solution. The results show that when the dosage of magnesium chloride is 1.2 times of stoicbiometric quantity, the reaction temperature is 297 K and the reaction time is 30 min, 99.46% of arsenic is removed, 0.34% Mo is lost, and mass concentration of the residual Mg2+ in the solution is 0.52 g/L. Mg2+ is removed from the ammonium molybdate solution with weak acid resin 724. In the solution, the pH value is about 9.2, and mass concentration of Mg2+ is 72 mg/L in the effluent until effluent/resin volume ratio is over 17 at the flow rate 1 mL/min. In addition, the operating exchange capacity of the resin is 6.58 g/L. The loaded resin can be stripped and regenerated with 2 mol/L HC1 solution, and the desorption ratio of Mg2+ is almost 100%.%镍钼矿常压空气氧化浸出液经N235萃取、氨水反萃后得到含砷的钼酸铵溶液.溶液中钼质量浓度达96.8g/L,砷质量浓度为8.75 g/L,加入氯化镁使砷形成砷酸铵镁沉淀而除去.实验结果表明:当氯化镁用量为理论量1.2倍,反应温度为297 K、反应时间为30 min时,溶液中残留砷质量浓度为46.7 mg/L,钼入渣率为0.34％,残余Mg2+质量浓度为0.52 g/L;除砷后的钼酸铵溶液用724弱酸性阳离子树脂吸附除镁;当料液pH为9.2、流速为1 mL/min、交换后液体积为树脂体积的17倍时,交换后液中镁质量浓度为72 mg/L,树脂操作质量浓度为6.58 g/L;负载镁的树脂用浓度为2 mol/L HCl溶液解吸,解吸率接近100％,并同时实现树脂再生.
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