有机溶剂中水的分光光度法测定

Spectrophotometric Method for the Determination of Water in Organic Solvents

在有机溶剂中有水存在时 ,氯醌酸发生离解 ,其最大吸收波长发生红移 ,且吸收强度显著增加。详细地研究了氯醌酸变色机理及其用于测定水的最佳条件 ,建立了一种新的测定有机溶剂中水含量的分光光度分析方法。测定了白酒、食用酒精与试剂无水酒精中的水含量 ,得到满意测定结果。测定线性范围为φ(H2 O) 0 0 2 %～ 10 % ,方法简单、灵敏度高、重现性好。对甲醇、异丙醇、丁酮、丙酮、乙腈、四氢呋喃中水的测定进行了实验 。

In the presence of a small amount of water, the chloranilic acid was disassociated. The absorption peak was bathochromic-shifted and the absorption intensity dramatically enhanced. Based on this fact, a spectrophotometric method was developed for determining water in many kinds of organic solvents. The mechanism and conditions for the determination were studied thoroughly. The water in alcohol samples (white wine, food alcohol and reagent alcohol) was detected with satisfactory results. The method was simple, sensitive and of good reproducibility. The linear range was φ(H 2O) 0.02%～10% in alcohol. The method was also used for the determination of water in other organic solvents such as methanol, 2-propanol, acetone, butanone, acetonitrile and tetrahydrofuran, and the calibration curves were obtained, respectively.