阳离子表面活性剂增敏催化光度法测定痕量铬(Ⅵ)

Catalytic Spectrophotometric Determination of \=Trace Chromium() with Sensiblization \=Effect of Cation Surfactant

基于存在增敏剂十六烷基三甲基溴化铵，铬（Ⅵ）催化过氧化氢氧化胭脂红酸的反应，拟定了测定痕量铬（Ⅵ）的新催化光度法。本法由于添加了十六烷基三甲基溴化铵，灵敏度提高３．３倍，测定铬（Ⅵ）含量的线性范围为０．００５～０．１６μｇ／ｍＬ，检出限为１．０×１０－３μｇ／ｍＬ，相对标准偏差为０．５％（ｎ＝９），可用于测定水样中的铬（Ⅵ）。

A new catalytic spectrophotometric method for the determination of trace amount of Cr() has been developed. The method is based on the catalytic effect of Cr() on the oxidation of cochineal acid by hydrogen peroxide in the presence of CTMAB as sensitizer.The sensitivity can be increased by 3.3 times after the addition of CTMAB. The linear range of determination is 0.0050.16 g/ mL, the detection limit is 1.010\+\{-3\} g/mL,and the relative standard deviation is 0.5%(n=9). The method can be used for the determination of Cr() in water samples.\=