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.
出处
《无机盐工业》
CAS
北大核心
2013年第7期21-23,共3页
Inorganic Chemicals Industry
关键词
磷酸二氢钠
阴离子杂质
诱导期
粒度分布
sodium dihydrogen phosphate
anionic impurities
induction period
particle size distribution
