有机溶剂中微量水的荷移光谱法测定

Spectrophotometric Determination of Micro Amount of Water in Organic Solvents

研究了氯冉酸与有机溶剂中水的反应 ,确定了反应条件。氯冉酸与水的络合物的最大吸收波长为5 3 0nm。在乙醇、甲醇、正丙醇、异丙醇、正丁醇、正庚醇、正己醇溶剂中 ,水的含量分别在 0～ 5 % (V V)或 0～8% (V V)范围内呈线性关系 ,相关系数为 0 .998或 0 .999;该方法重现性好 ,灵敏度高 ,操作简单 ,用于测定乙醇中微量水的含量 ,与标准值相符 ;加入回收法测得甲醇中水的回收率分别为 98%～ 1 0 3 % ,结果令人满意。

The reaction between chloranilic acid and water in organic solvents have been studied. The reaction product has maximum absorption at 530 nm, The linear range is 0 similar to5.0% (V/V) or 0 similar to8.0 % (V/V) for the determination of water in methanol, ethanol, n-propyl alcohol, 2-propanol, n-butyl alcohol, heptanol, n-hexanol. Correlation coefficients are 0.998 similar to 0.999. The assay results for ethanol master sample are satisfactory. The recovery of water in methanol is 98 % similar to 103 %. This is a simple, sensitive and reproducible method for determining water in alcohol.