磷矿脱镁废液制备氟化镁工艺研究

低品位磷矿脱镁会产生大量废液,主要含有镁离子、磷酸根、钙离子、二价铁离子、铝离子、硫酸根等。研究了以脱镁废液为原料,通过预处理脱除杂质离子后加入氟化铵溶液制备氟化镁的方法。脱镁废液除杂优化条件:pH为9.0~9.5,反应温度为60 ℃。在此条件下溶液中磷酸根、钙离子、二价铁离子、铝离子脱除率分别为96.89%、95.41%、100%、100%。复分解反应优化条件:反应温度为60 ℃,干燥温度为300 ℃。通过此方法制得的氟化镁符合YS/T 691—2009《氟化镁》中MF-2的要求,氟收率为92%以上。该制备工艺简单,原料利用率高,具有较高的经济效益。

Study on the preparation of magnesium fluoride from demagging liquor of phosphate ore

Waste liquid produces from the demagging of low grade phosphate ore, mainly containing magnesium,phosphate,calcium,ferric,aluminum,and sulfate plasma etc..The method of preparing magnesium fluoride by adding ammonium fluo-ride solution after removing impurity ion from magnesium removal waste solution by pretreatment was studied.The optimized purification conditions of demagging liquor were:pH 9.0~9.5,and the reaction temperature of 60 ℃.Under these conditions,the removal rates of phosphate,calcium,ferric and aluminum ions were 96.89%,95.41%,100% and 100%,respectively.Double decomposition reaction optimization conditions:reaction temperature was 60 ℃,and the drying temperature was 300 ℃.The magnesium fluoride obtained through this process conformed to the requirements of MF-2 specified in the Stan-dard,YS/T 691—2009,with a fluorine yield of over 92%.This method had high economic benefits as its process was simple and its utilization rate of raw material was high.