萃取结晶法应用于磷酸二氢锂生产研究

Study on application of extractive crystallization method in production of lithium dihydrogen phosphate

对磷酸二氢锂生产中萃取结晶回收无机盐的过程进行了研究,分别考察了不同萃取剂及用量、结晶温度、结晶时间等因素对磷酸二氢锂产率的影响以及不同结晶方式对产品粒度的影响。结果表明,乙醇为较适合的萃取剂;在乙醇与磷酸质量比为2∶3,结晶温度0℃,结晶时间120min的条件下,磷酸二氢锂的产率达95%以上。对制取的磷酸二氢锂产品进行了X-射线衍射分析,发现其产品质量达到了电池级要求。

The process of recovery of inorganic salt by extraction crystallization in the production of lithium dihydrogen phosphate were studied by investigating effects of type and concentration of extractant,crystallization temperature and time and other factors on the productivity of lithium dihydrogen phosphate and impact of the crystallization methods on the particle size.The results show that ethanol is a suitable extractant.With the conditions of the mass ratio between ethanol and phosphoric acid being2∶3,the crystallization temperature 0 ℃,crystallization time120 minutes,the productivity of lithium dihydrogen phosphate could be up to 95%and more.The analysis of X-ray diffraction in the preparation of lithium dihydrogen phosphate products showed that the products in quality reach the battery grade.