典型阴离子杂质对磷酸二氢钠结晶过程影响  

Research on effects of typical anionic impurities on crystallization process of sodium dihydrogen phosphate

作　　者：张晓光[1] 

机构地区：[1]宁夏大学化学化工学院,宁夏银川750021

出　　处：《无机盐工业》2013年第7期21-23,共3页Inorganic Chemicals Industry

摘　　要：采用间歇冷却结晶法研究了工业上生产磷酸二氢钠的原料湿法磷酸中典型阴离子杂质SO42-、F-、Cl-等对磷酸二氢钠结晶过程的影响,并以诱导期表征晶核形成,以结晶速率表征晶体生长,以粒度分布、长径比衡量晶体形态。研究结果表明,随着SO42-含量的增加,磷酸二氢钠诱导期和晶体平均粒径逐渐降低,而结晶速率呈现先增加后降低的趋势;随着F-含量的增加,诱导期、结晶速率、平均粒径均逐渐增大;随着Cl-含量的增加,诱导期减小,而结晶速率变大,平均粒径先增大后减小。此研究成果可用于指导湿法磷酸制备磷酸二氢钠的工业生产。Intermittent cooling-crystallization method was employed to find out the influences of contents of typical anionic impurities,such as SO42-,F-,Cl-in the wet process phosphoric acid,the raw material of sodium dihydrogen phosphate,on the crystallization process of sodium dihydrogen phosphate.Induction period,crystallization rate,particle size distribution,and slenderness ratio are applied to characterize crystal nucleation,crystal growth,and crystal morphology,respectively.Experimental results indicate that with the increase of SO42-content,the induction period and the average particle size decrease,whereas the crystallization rate increases firstly,and decreases afterwards;with the increase of F-content,the induction period,crystallization rate and average particle size all increase gradually;with the increase of Cl-content,induction period decreases,crystallization rate increases,and average particle size increases at first,and then decreases.These research results can be used to guide the industrial production of sodium dihydrogen phosphate from wet process phosphoric acid.

关 键 词：磷酸二氢钠 阴离子杂质 诱导期 粒度分布 

分 类 号：TQ126.35[化学工程—无机化工]