摘要
研究了氨中和法净化湿法磷酸的效果,筛选出了适宜的结晶改善剂。研究结果表明:在中和终点pH为4.0时,铝离子、铁离子、氟离子的净化率均达到98%以上,镁离子的净化率为50%,生成的磷酸一铵结晶细小,呈针状。氟离子作为结晶改善剂,能明显消除铝离子对于结晶的影响,但对于铁离子的效果不明显;螯合结晶改善剂Chet-a可以基本消除铁离子的影响。采用氟离子和Chet-a联合作用,可以基本消除杂质对结晶的影响,改善晶形,产品磷酸一铵长径比达3.5:1,可以生产出合格的产品。
Purification effect of phosphoric acid by wet process （WPA） by means of ammonium-neutralization method was studied and appropriate crystal modifiers were selected by sifting.Study results showed that the purification rate of Al,Fe,and F ions were all over 98%,while purification rate of Mg ions was only 50% at the final neutralization point （pH=4.0）;and the produced monoammonium phosphate（MAP）was small and fine needle-like crystals.As the crystal modifier,F ion could obviously decrease the influence of Al ion on crystallization,but it did not have obvious effect on Fe ion.Chelated crystal modifier,Chet-a could basically eliminate the impact of Fe ion.Combination of F ion and Chet-a could basically eliminate the impact of impurities on crystallization and crystal morphology could also be improved.Slenderness ratio of MAP product could reach 3.5∶1 and the quality could match the related Standard.
出处
《无机盐工业》
CAS
北大核心
2010年第4期49-51,共3页
Inorganic Chemicals Industry
基金
国家十一五攻关项目:西部中低品位磷矿资源化深度开发关键技术研究(2005BA207C)
关键词
磷酸一铵
结晶晶形
杂质
结晶改善剂
monoammonium phosphate（MAP）
crystal morphology
impurity
crystal modifier
