METHOD FOR PRODUCING ISOBUTYLENE AND METHANOL

摘要

PURPOSE: To provide a method for economically obtaining isobutylene and methanol. CONSTITUTION: This method uses the following steps: the first step; obtaining isobutylene, methanol and a heavy material containing a by-produced dialkylether as well as dimmer and trimer of isobutylene by subjecting methyl tert-butyl ether to decomposition reaction in the presence of a solid acid catalyst/the second step; washing the reaction liquid obtained from the first step with water to separate into an oil layer and a water layer/the third step; subjecting the oil layer to distillation to obtain a fraction containing isobutylene and the dialkylether from the top of the distillation column and to obtain a fraction containing methyl tert-butyl ether and the heavy material, or the like, from the bottom of the distillation column/the forth step; subjecting the water layer to distillation to obtain a fraction containing methanol from the top of the distillation column, to obtain a fraction containing water from the bottom of the distillation column and to obtain a fraction rich in tart-butanol from a side-cut of the distillation column and to recycle at least a part of the fraction obtained from the side-cut to the first step.