青海盐湖水氯镁石制备氢氧化镁的进展

Research Progress in Preparation of Magnesium Hydroxide from Bischofite in Qinghai Salt Lakes

青海柴达木盆地盐湖提钾后产生的废卤水经日晒蒸发形成巨量的水氯镁石,对盐湖生态环境造成严重影响。利用水氯镁石制备氢氧化镁是盐湖固废减量化、无害化、资源化利用的有效途径。文章介绍了青海盐湖水氯镁石的成因、典型组成及储量规模,综述了利用盐湖水氯镁石制备氢氧化镁的典型工艺。对直接沉淀法、水热法、声化学合成法、微乳液法、电沉积法制备氢氧化镁的技术原理、工艺流程及研究现状进行了介绍,并对其技术特点进行分析比较。介绍了电沉积法制备高纯氢氧化镁的研究进展、优势及尚需解决的问题。

The waste brine from potassium extraction process with salt lake resources in Qinghai Province is evaporated by sun to form a huge amount of bischofite,which threatelled on the ecological environment of the salt lakes.The preparation of magnesium hydroxide from bischofite is an effective way to utilize the solid waste of salt lakes innocuously,resourcefully and decrementally.This paper introduces the genesis,chemical composition and reserve scale of bischofite from Qinghai salt lakes,and summarizes the methods of preparing magnesium hydroxide from salt lake bischofite.The technical principles,process flow and re-search status of direct precipitation,hydrothermal method,acoustic chemical synthesis,microemulsion method and electrodeposition method for the preparation of magnesium hydroxide are introduced,and their technical characteristics are analyzed and compared.The research progress,advantages and technical diffi-culties to be solved for the preparation of high-purity magnesium hydroxide by electrodeposition are intro-duced.