Abstract: Dialkylbenzene sulfonic acid was synthesized by olefin sulphonate and alkyl benzene using sulfuric acid as the catalyst and the effect of the temperature and the mol-ratio of the reactant and the catalyst, air, etc. on the final product was investigated. The results show that an optimal product can be obtained at the conditions of a temperature of 138 ℃, a mol ratio between alkyl benzene, olefin sulphonate and sulfuric acid of 1.05:1:0.1 and an oxygen introduction. The synthesized dialkylbenzene sulfonic acid was then neutralized and purified to obtain dialkylbenzene sulphonate, which is proved to contain a low cmc(0.11mM) by a performance test.

Key words: Dialkylbenzene sulphonate, Synthesis, Critical micelle concentration