摘要
研究了在pH 4.5的柠檬酸盐缓冲溶液介质中,利用硫脲对钒(Ⅴ)催化溴酸钾氧化邻氨基酚显色反应的阻抑作用,用萃取平衡控制反应时间和水相中邻氨基酚的浓度及反应程度,通过测量424 nm下有机相的吸光度,建立了萃取催化光度法测定痕量硫脲的新方法.在最佳实验条件下,测定硫脲的线性范围为0.020～1.20 μg/mL,检出限为1.4×10-8 g/mL.对1.00μg/mL硫脲进行11次平行测定的相对标准偏差为3.8%.用于水样中硫脲的测定,结果满意.
A new extraction inhibition spectrophotometric method for the indirect determination of trace thiourea was developed.It was based on the inhibition effect of thiourea on the catalyzing of vanadium(Ⅴ)on the oxidation of o-aminophenol by potassium bromate in weak acidic medium at pH4.5.The reaction time,concentration of o- aminophenol in aqueous phase and degree of reaction were controlled by extraction equilibrium.The absorbance of organic phase was measured at424nm.Under the optimum conditions,the linear range of the calibration curve was0.020～1.20μg/mL.The detection limit was1.4×10 -8 g/mL and the relative standard deviation(n=11)was3.8%for1.00μg/mL thiourea.The method has been apˉplied to the determination of thiourea in water with satisfactory results.
出处
《分析测试学报》
CAS
CSCD
北大核心
2005年第2期54-56,共3页
Journal of Instrumental Analysis
基金
安徽省教育厅自然科学基金资助项目(2001KJ196
2004KJ320)
淮北市科技计划基金资助项目(040145)
关键词
萃取
阻抑光度法
硫脲
钒
邻氨基酚
Extraction
Inhibition spectrophotometry
Thiourea
Vanadium
o-aminophenol
