The Process Study On The Separation M-cresol And P-cresol Mixture By Alkylation Method

M-cresol and p-cresol is a very important intermediate in the fine chemical industry, have a very wide range of applications in medicine, pesticides, dyes, antioxidants and other fields. M-cresol and p-cresol mixture are difficult to separate by the traditional distillation method as the very close boiling point. There are a lot of method to separate the m-cresol and p-cresol mixture, such as alkylation method, crystallization, dissociation extraction and so on, but these method all have some disadvantages, domestic don’t have the industrialization of cresol separation, so it’s significant to improve the cresol separation process.In this paper, we used m-cresol and p-cresol mixture as raw material, using alkylation method to separate m-cresol and p-cresol mixture with the existence of catalyst. Through the experiment study the influence of the reaction by type of catalysts, reaction device, isobutene flow rate, reaction temperature, reaction time, including of isobutene polymerization, then get the best process condition for separation of m-cresol and p-cresol mixture by orthogonal test: isobutene flow rate is8.49min-1, reaction temperature is55℃, reaction temperature is2h, On this condition, conversion of cresol is close to100%, yield of di-tert butyl cresol is close to90%. Through the reasonable hypothesis and on the basis of the tower reactor experimental data, done the dynamics simulation of the alkylation reaction, obtained the activation energy and kinetic equation. Finally, this paper take the vacuum distillation product as raw material, study the influence of the reaction by change the catalyst, obtained the high purity p-cresol.