Preparation method of diisobutyl phthalate

According to the preparation method of the diisobutyl phthalate provided by the invention, the diisobutyl phthalate is prepared by using the composite catalyst compounded by p-toluenesulfonic acid and acid sulfate, the reaction condition is mild, the pollution is less, the problem of serious corrosion to equipment is solved, and the production cost is reduced. The composite catalyst is used, p-toluenesulfonic acid and acid sulfate (sodium hydrogen sulfate) are compounded to have the catalytic activity similar to that of concentrated sulfuric acid, and after the reaction is completed, the defects that a sulfuric acid catalyst has many side reactions, environmental pollution is serious, and equipment is prone to corrosion are overcome. The activity temperature of p-toluenesulfonic acid and acid sulfate (sodium hydrogen sulfate) is 120-140 DEG C, the temperature is low, the activity is good, and the p-toluenesulfonic acid and acid sulfate (sodium hydrogen sulfate) can be easily applied to production. 本发明提供一种邻苯二甲