微波消解-流动注射比浊法快速测定磷石膏中的SO_3  

Rapid determination of the SO_3 content in phosphogypsum samples by microwave digestion and flowinjection turbidimetry

作　　者：张志永[1] 史文慧[1] 张志业[1] 张必江 阮永刚 周学克 张应虎 王辛龙[1] 

机构地区：[1]四川大学化学工程学院,成都610065 [2]云南云天化股份有限公司云峰分公司,宣威655413

出　　处：《分析试验室》2015年第12期1379-1382,共4页Chinese Journal of Analysis Laboratory

基　　金：国家"863"项目课题(2011AA06A106);云南省省校省院合作计划(2014IB004)资助

摘　　要：以磷石膏和磷石膏不同分解产物(含CaSO_4和CaS)为原料,采用微波消解,考察了消解压力、HCl浓度、消解时间对样品中硫酸钙溶出率的影响,获得了适宜的消解条件。消解压力为0.4MPa,HCl浓度为2mol/L,消解时间为60s时,磷石膏中CaSO_4的溶出率为98.3%。在此条件下,对磷石膏及磷石膏不同分解产物中SO_3含量进行测定,与传统分析方法相比,微波消解磷石膏样品结果的相对标准偏差均小于4%,方法的加标回收率为101%。最后,通过微波消解同流动注射比浊法的联用,对磷石膏固体样品中的SO_3含量进行测定,微波消解-流动注射比浊法可实现磷石膏不同分解产物样品中的SO_3含量的快速测定,同标准重量法测定结果相比,其相对标准偏差均小于5%。The effects of digestion pressure, acid concentration and digestion time rock on dissolution rates of calcium sulfate were studied to obtain the optimal digestion conditions with phosphogypsum and phosphogypsum decomposition product （containing calcium sulfate and calcium sulfide） as raw materials. The results showed that the dissolution rate of calcium sulfate was 98.3% under the conditions of digestion pressure of 0. 4 MPa, the amount of hydrochloric acid was 20 mL with content of 2 moL/L, and digestion time was 60 s. Under the optimal conditions, the SO3 content of phosphogypsum and phosphogypsum decomposition products were obtained, and the results showed that the relative standard deviation of phosphogypsum samples results dissolved by hybrid microwave was less than 4% comparing with traditional digestion method, and standard addition recovery rate of the method was 101%. Based on above results, the SO3 content of phosphogypsum in solid samples were measured by microwave digestion combined with flow-injection turbidimetry. The results showed that microwave digestion combined with flow-injection turbidimetry could achieve determination of the SO3 content of phosphogypsum decomposition product rapidly, and the relative standard deviation was less than 5% comparing with the results determined by standard gravimetric method.

关 键 词：微波消解 流动注射比浊法 磷石膏 三氧化硫 

分 类 号：TQ125[化学工程—无机化工]