干法发汗提纯半水磷酸晶体的实验研究  

Purification of Phosphoric Acid Hemihydrate Crystal by Dry-sweating

作　　者：王保明[1] 李军[1] 贾旭宏[1] 齐亚兵[1] 罗建洪[1] 

机构地区：[1]四川大学化学工程学院,四川成都610065

出　　处：《四川大学学报（工程科学版）》2013年第1期192-197,共6页Journal of Sichuan University (Engineering Science Edition)

基　　金：国家科技支撑计划资助项目(2007BAE28B01)

摘　　要：采用干法发汗提纯半水磷酸晶体制备高纯磷酸。考察了发汗过程中发汗温度、冷却速率、酸浓度、发汗时间等参数对Mg和Sb脱除及净化效率的影响。结果表明:发汗温度越高,杂质脱除越快,净化效率越低,而且所得产品杂质含量也越少;结晶过程中的冷却速率越大,所得晶体中杂质含量也越多,杂质在发汗过程中脱除也越快,净化效率也越低,但是最终产品杂质含量越高;半水磷酸晶体中初始杂质含量越少,发汗所得产品纯度也越高,因此干法发汗可以用来精制磷酸。A method of dry-sweating was applied to. purify phosphoric acid hemihydrate crystals to obtain high purity phosphoric acid. The effects of operating parameters, such as sweating temperature, cooling rate, phosphoric acid concentration and sweating time on the removal and purification efficiency of Mg and Sb were investigated. The experimental results showed that the content and purification efficiency of impurities decrease with the increase of sweating temperature, the content of impurities in the product obtained at higher sweating temperature are lower. The content of impurities in the crystals formed at higher cooling rate during crystallization are more, and the impurities can be removed easily during dry-sweating, moreover the purification efficiency of impurities are lower, however the content of impurities in the final product are more. The less the initial content of impurities in the crystals is, the higher the purity of product is. Therefore, dry-sweating can be used to fine phosphoric acid.

关 键 词：磷酸 提纯 干法发汗 

分 类 号：TQ028.65[化学工程] TQ126.35