摘要
基于在H2SO4介质中,溴化十六烷基吡啶(CPB)对于KBrO3氧化曙红Y褪色反应的增敏作用和水杨酸对此反应的阻抑作用.建立了阻抑动力学光度法测定痕量水杨酸的新方法.研究了该反应的最适宜的条件和动力学参数.方法的表观摩尔吸光系数为3.79×105L·mol-1·cm-1,线性范围为:0.040~0.50mg/L,检出限为0.020 mg/L.方法用于复方苯甲酸搽剂中水杨酸的测定.对阻抑褪色反应的机理进行了探讨.
An inhibitory kinetic-spectmphotometric method for the determination of trace salicylic acid was proposed. The method was based on the enhanced sensitivity of cetyl pyridinium bromide on the oxidition of eosine Y by KBrO3 , and on inhibitory effect of salicylic acid on the reaction in the sulfuric acid medium. The kinetic behavior of this reaction was investigated. The linear re- sponse range and detection limit are 0.040 - 0.50 mg/L and 0. 020 mg/L respectively. The apparent molar absorptivity is 3.79 × 10^5 L·mol^-1·cm^-1 This mohhod has been applied to the determination of salicylic acid in tincture of compound benzoic acid with satisfactory resuits. The mechanism of the inhibition about the discolorition reaction are discussed.
出处
《分析试验室》
CAS
CSCD
北大核心
2005年第12期47-50,共4页
Chinese Journal of Analysis Laboratory