一、前言测定甲苯磺酸混合物中的邻位、间位、对位三种异构体的含量是不容易的事。本文介绍我们用紫外分光光度分析法及数学处理法来测定上述三种异构体的含量。用紫外分光光度法分别测定邻位、间位和对位甲苯磺酸的摩尔消光系数∈,Shraga等曾作了试验,当水溶液中有相当过量的硫酸(超过600:1)时没有干扰,含有中等含量的甲苯(如0.014克/升至0.1克/升)影响也很小。1963年Hans Cerfontain等 I. INTRODUCTION It is not easy to measure the content of three isomers of toluenesulfonic acid in the ortho, meta and para position. This article describes our use of UV spectrophotometry and mathematical methods to determine the content of these three isomers. The molar extinction coefficients ∈ of ortho, meta and p-toluenesulfonic acid were determined by UV spectrophotometry, respectively. Shraga et al. Have tested that there is no interference when the aqueous solution contains a considerable excess of sulfuric acid (over 600: 1) Toluene at a moderate level (eg, 0.014 g / L to 0.1 g / L) has little effect. 1963 Hans Cerfontain et al