表面活性剂增敏动力学光度法测定痕量铬Ⅵ  

Catalytic kinetic spectrophotometric determination of trace chromiumⅥ with sensitization effect of surfactant

作　　者：莎仁[1] 韩明梅[1] 

机构地区：[1]内蒙古师范大学化学系,内蒙古呼和浩特010022

出　　处：《冶金分析》2005年第3期48-51,共4页Metallurgical Analysis

基　　金：内蒙古自治区自然科学基金资助项目(200408020213)。

摘　　要：基于弱酸性介质中,十六烷基三甲基溴化铵(CTMAB)对Cr(催化过氧化氢氧化次甲基蓝褪色反应的增敏作用,建立了测定Cr(的表面活性剂增敏催化动力学光度法。加入CTMAB,灵敏度约提高5倍。方法线性范围为0·05~48·0μg/L,检出限为0·047μg/L,催化反应表观活化能为Ea=71·1kJ/mol,反应速率常数为k=1·15×10-3s-1。用于水样和钢样中铬(的测定,结果满意。A catalytic kinetic spectrophotometric method for the determination of trace CrⅥ has been developed.The method is based upon the catalytic effect of CrⅥ on the oxidation of fading reaction of methylene blue by hydrogen peroxide in weak acid medium.The sensitivity of reaction can increase about 5 times after the addition of CTMAB.The linear range of determination was 0.05-48.0 g/L,and the detection limit is 0.047g/L.The apparent activation energy of the reaction is found to be 71.1kJmol^(-1),and the rate constant is 1.1510^(-3)s^(-1).The method can be used for the determination of CrⅥ in water samples and steel samples.

关 键 词：催化动力学光度法 十六烷基三甲基溴化铵 次甲基蓝 铬 

分 类 号：O657.32[理学—分析化学]