一种用于湿法磷酸工艺中直接测定超高量P2O5的自动分析法  

An automatic analysis method for directly measuring ultra-high P2O5 in wet process phosphoric acid process

作　　者：苏武 李永生[1] SU Wu;LI Yong-sheng(School of Chemical Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学化学工程学院

出　　处：《应用化工》2020年第1期252-255,共4页Applied Chemical Industry

基　　金：国家重点研发计划(2016YFD0200404);四川省科技创新人才项目资助(2018RZ0145)

摘　　要：采用磷钼酸光度法自动快速分析湿法磷酸中超高浓度P2O5(3~200 g/L)含量,考察了显色剂浓度、酸度、反应盘管RC长度、稀释盘管DC长度、温度等对P2O5测定的影响。优化的测试条件为:反应试剂由15 mmol/L钼酸铵、9 mmol/L偏钒酸铵及0.7 mol/L HNO 3构成,RC为25 cm,DC 2为500 cm。结果表明,本方法的直接测定P2O5的范围达到了工业生产的控制要求(3~200 g/L P2O5),重现性较好(RSD≤0.63%,n=11),分析速度为20样/h,实样加标回收率在98%~104%,测定结果与喹钼柠酮重量法一致,而且不会受到湿法磷酸生产中共存的高浓度SO^2-4、F^-的干扰。Automatic and rapid analysis for P2O5(3~200 g/L)based on phosphomolybdic acid spectrophotometry,and investigated the effects of developer concentration,acidity,reaction coil RC length,dilution coil DC length,and temperature on the determination of P2O5.The optimized test conditions were as follows:the reagent was composed of 15 mmol/L ammonium molybdate,9 mmol/L ammonium metavanadate and 0.7 mol/L HNO 3,RC was 25 cm,and DC 2 was 500 cm.The results show that the direct measurement of the method of P2O5 has reached the control range of WPA industrial production(3~200 g/L),in which its reproducibility(RSD≤0.63%,n=11)is superior to the manual methods currently used,and its analysis speed is up to 20 sample/h,the standard addition recovery in the actual sample is between 98%~104%which satisfied the requirements of analysis chemistry.The ultra-high contents of SO^2-4 and F^-coexisting in WPA production do not affect the proposed method and the measurement results are consistent with the quin molybdenum ketone gravimetric method.

关 键 词：湿法磷酸工艺 超高浓度 五氧化二磷 自动分析 

分 类 号：TQ442.1[化学工程—化学肥料工业]