An improved preparation experiment of p-toluenesulfonic acid was carried out by adding dropwise toluene to exceed sulfuric acid at 90～100℃,based on the principle of increasing yield of p-toluenesulfonic acid from toluene sulfonation at higher temperature and p-toluenesulfonic acid monohydrate being crystallized out from dilute sulfuric acid.
根据提高温度有利于对甲苯磺酸的生成以及对甲苯磺酸一水化合物能从稀硫酸中结晶出来的原理,采用浓硫酸过量,甲苯滴加到90~100℃的浓硫酸中反应,改进了对甲苯磺酸制备实验;改进的方法制备收率高,反应操作简单,更有利于实验教学。