一、引言我们和有关工厂合作,进行了对氯甲苯均相催化氧化制取对氯苯甲酸新工艺的研究。为控制付反应及了解成品的质量,我们采用了高效液相色谱对中间产物及成品质量等一系列问题进行监测。其原因在于:(1)化学分析法只能测定酸值及皂化值,并且分析时间太长,又不能测定反应过程中的对氯苯甲醛和对氯甲苯等。(2)用气相色谱法分析对氯苯甲醛等较合适,但分析对氯苯甲酸必须先转化成酯类。其中用《四甲基铵盐热解法制备甲酯》(参1)被认为是最简便的,其手续为:“取强碱性阴离子交换树脂10克,用氢氧化钠水溶液把离子 I. INTRODUCTION We cooperated with relevant factories to conduct a research on the new process of preparing p-chlorobenzoic acid by homogeneous catalytic oxidation of chlorotoluene. To control the payback and to understand the quality of the finished product, we used HPLC to monitor the quality of intermediates and finished products. The reason is: (1) chemical analysis method can only determine the acid value and saponification value, and the analysis time is too long, and can not be measured during the reaction of p-chlorobenzaldehyde and p-chlorotoluene and so on. (2) The analysis of p-chlorobenzaldehyde by gas chromatography is more suitable, but analysis of p-chlorobenzoic acid must first be converted to esters. Which use “tetramethylammonium pyrolysis of methyl ester” (reference 1) is considered the most simple, the procedure is: "Take strong alkali anion exchange resin 10 grams, with sodium hydroxide solution to the ion