紫外分光光度法对苯酚、苯胺和苯甲酸的同时测定方法的研究

利用紫外分光光度法的吸光度加和性原理,对苯酚、苯胺和苯甲酸的同时测定方法进行了研究.通过调整待测物质溶液的pH值,可以使其分光光度法的吸收峰发生红移(或蓝移),从而有利于确定该物质的最佳吸收波长.对苯酚、苯胺和苯甲酸的分析测定表明,在碱性介质中该系列化合物的吸光度具有较好的加和性,其相对误差在10%～15%之间,适于多组分同时测定.本方法的苯酚、苯胺和苯甲酸的线性范围均为0～70 mg/L;加标回收率分别为95.8%～107.8%,97.6%～117%和93.7%～108.5%,测定2组水样时的相对标准偏差分别为1.84%、3.20%,2.71%、1.06%和2.61%、5.10%.

On simultaneous determination of phenol aniline and benzoic acid by ultraviolet absorption spectrometry

The present paper introduces the authors' analysis and study of the simultaneous determination of the content of phenol, aniline and benzoic acid in the mixed solution by following the additive character's principle of the Ultraviolet Absorption Spectrometry's absorbance. By adjusting the pH value of the solution, the absorption peak of Ultraviolet Absorption Spectrometry may appear from the red shift(or blue shift), which is useful to choose the optimal absorption wavelength. The experimental results show that the absorbance additive feature of phenol, aniline and benzoic acid could be used to determine the content simultaneously in the alkaline medium with satisfactory results while the relative error is 10%15%. When the linear ranges of calibration curves were 070 mg/L for phenol, aniline and benzoic acid, the recoveries of standard would be 95.8%107.8%, 97.6%117% and 93.7%108.5%, respec- tively, and also the relative standard deviations would be 1.84%, 3.20%, 2.71%,1.06% and 2.61%,5.10% for the two groups of wastewater respectively.