对乙酰基偶氮氯膦褪色光度法测定粉煤灰中微量铈(Ⅳ)  

Decoloring spectrophotometric determination of micro cerium (Ⅳ) in fine coal ash with p-acetylchlorophosphonazo

作　　者：罗道成[1] 刘俊峰[1] 

机构地区：[1]湖南科技大学化学化工学院,湖南湘潭411201

出　　处：《冶金分析》2007年第12期32-34,共3页Metallurgical Analysis

摘　　要：研究了在1.0mol/LH2SO4介质中,Ce(Ⅳ)氧化对乙酰基偶氮氯膦(CPApA)的褪色反应,加入TritonX-100可提高反应的灵敏度,褪色程度与Ce(Ⅳ)量线性相关,据此建立了一种测定微量Ce(Ⅳ)的新分光光度法。结果表明,体系的最大吸收波长为535nm,表观摩尔吸光系数为9.37×104L.mol-1.cm-1。Ce(Ⅳ)的质量浓度在0～1000μg/L范围内呈线性关系。讨论了反应介质、温度、时间、试剂用量及共存离子干扰等对反应的影响。本法结合PMBP-苯萃取分离,应用于粉煤灰中微量铈的测定,加标回收率在97.6%～103.2%之间,RSD(n=6)为1.3%～1.6%。The decolorization of p-acetylchlorophosphonazo（CPApA）oxidized by trace cerium（IV） has been studied in the medium of 1.0 mol/L H2SO4. The sensitivity of reaction can be remarkably improved by addition of Triton X-100 and its fading extent is linear with the contents of cerium（Ⅳ）. Based on this, a new spectrophotometric method for the determination of micro cerium（Ⅳ） was established. The results show that the maximum absorption wavelength of the system is 535 nm, and the apparent molar absorptivity is 9.37×10^4L·mol^-1·cm^-1. The linear is in the range of 0--1 000 μg/L for cerium（IV）. The effects of medium, temperature, time, reagent dosage and the interference of coexisting ions on reaction are discussed. Combined with the PMBP--benzene extraction and separation, the method has been applied to the determination of micro cerium in fine coal ash with recovery of standard addition of 97.6%-103.2% and RSD （n = 6） of 1.3%--1.6%.

关 键 词：铈(Ⅳ) 褪色光度法 对乙酰基偶氮氯膦 粉煤灰 

分 类 号：O657.3[理学—分析化学]