杂质对磷酸脲结晶的影响.docxVIP

2 81 1FINE CHEMICALS2 0 1 1 年 1 1 月Nov． 2 0 1 1杂质对磷酸脲结晶的影响胡秀英，马迪，陈锦( 江苏技术师范学院 化学与环境工程学院，江苏 常州213001)摘要:采用间歇结晶法考察了杂质 Al3 + 、Fe3 + 、F － 、Mg2 + 、SO2 － 对磷酸脲结晶收率、析晶时间、产品粒度、晶体形4态等的影响。结果表明，Al3 + 、Fe3 + 对磷酸脲结晶过程影响显著，若无晶种加入，体系降至常温仍无晶体析出; 向 反应体系中加入其质量 1% 的晶种时，随着掺杂 Al3 + 、Fe3 + 质量分数的增加，磷酸脲收率逐渐下降，析晶时间显 著延长，磷酸脲粒度显著减小，产品晶形不规则，晶体聚集明显，Al3 + 的影响比 Fe3 + 略大; 随着掺杂 F － 质量分数 的增加，磷酸脲收率逐渐增大，析晶时间无明显变化，粒度先逐渐减小，后因小颗粒间相互嵌入聚集导致表观粒度逐渐增大，产品晶形不规则; 掺杂 Mg2 + 、SO2 － 后磷酸脲晶体规则，晶形仍为棱柱状，颗粒分散性好。4关键词:杂质; 磷酸脲; 结晶; 分离提纯技术中图分类号:TQ126. 3 文献标识码:A文章编号:1003 － 5214( 2011) 11 － 1107 － 05Effect of Impurities on the Crystallization of Urea PhosphateHU Xiu-ying，MA Di，CHEN Jin( School of Chemical and Environmental Engineering，Jiangsu Teachers University of Technology，Changzhou 213001，Jiangsu，China)Abstract: The effect of such impurities as ions Al3 + ，Fe3 + ，F － ，Mg2 + and SO2 － on the crystallization4yield of urea phosphate ( UP ) ，its crystallization period，product size and crystal morphology wasstudied by means of batch crystallization process． The results show that the dopant of Al3 + ，Fe3 + had significant effect on UP crystallization process，and without the crystal seed added into the reaction system，no crystals separated out when the system was cooled to normal temperature． Under the condition of 1% crystal seed added，with the increase of Al3 + ，Fe3 + mass fraction，the yield of UP gradually decreased，the crystallization period was significantly prolonged，the product size was obviously reduced and the crystal morphology became irregular． Moreover，the aggregation degree was higher． The effect of Al3 + was somewhat greater than that of Fe3 + on the foregoing aspects． With the increase of F － mass fraction，the yield of UP gradually decreased，the crystallization period did not change significantly，the product size decreased at first and then increased slowly because of the embedding of the particle into each other