结晶净化法提纯磷酸的研究  

Purification of phosphoric acid by crystallization

作　　者：周骏宏[1] 李军[2] 黄平[2] 王保明[2] 

机构地区：[1]黔南民族师范学院,贵州都匀558400 [2]四川大学化工学院

出　　处：《无机盐工业》2010年第2期46-48,共3页Inorganic Chemicals Industry

基　　金：国家"十一五"科技支撑计划项目(2007BAE58B01)

摘　　要：以工业磷酸为原料,分别采用悬浮结晶及倾斜塔结晶提纯磷酸,以铁、氟、硫酸根、氯、镁、钾为代表,考察悬浮结晶的杂质的脱除效果。实验结果表明,杂质含量随着悬浮结晶的重复次数增加降低,经过5次重复结晶后,磷酸中铁的质量分数由349.9 mg/kg降低到2.7 mg/kg,氟质量分数由55.9 mg/kg降低到0.6 mg/kg,硫酸根质量分数由1 047.4 mg/kg降低到0.5 mg/kg,钾质量分数由87.1 mg/kg降低到9.1 mg/kg,镁质量分数由153.9 mg/kg降低到7.8 mg/kg,氯质量分数由250.4 mg/kg降低到7.6 mg/kg;以铁为代表,考察倾斜塔结晶的杂质的脱除效果。结果表明,倾斜塔结晶提纯磷酸的效果相当于1.9次悬浮结晶。Suspension crystallization and inclined column crystallization were adopted respectively to purify phosphoric acid with industrial grade phosphoric acid as raw material, hnpurity removal effect of suspension crystallization was investigated by taking iron, fluorine, sulfate radical, chlorine, magnesium, and potassium as representatives. Resuhs showed that impurity contents in phosphoric acid decreased with the increase of suspension crystallization repetition. After five times of crystallization, Fe^3＋ content in phosphoric acid decreased from 349.9 mg/kg to 2.7 mg/kg, F^- content decreased from 55.9 mg/kg to 0.6 mg/kg, SO2 content decreased from 1 047.4 mg/kg to 0. 5 mg/kg, K^＋ content decreased from 87.1 mg/kg to 9.1 mg/kg, Mg^2＋ content decreased from 153.9 mg/kg to 7.8 mg/kg, and Cl content decreased from 250.4 mg/kg to 7.6 mg/kg. Impurity removal effect of inclined column crystallization was also investigated by taking Fe^3＋ as representative. Results showed that purifying effect of inclined column crystallization was equal to 1.9 times of suspension crystallization.

关 键 词：磷酸 悬浮结晶 硫酸根 

分 类 号：TQ126.35[化学工程—无机化工]