METHOD OF PRODUCING DIMETHYL TEREPHTHALATE AND INTERMEDIATE PRODUCTS OF DIMETHYL TEREPHTHALATE PRODUCTIONS

A process for the production of dimethyl terephthalate and intermediate products of the dimethyl terephthalate manufacture from the high-boiling by-products obtained during the air oxidation of p-xylene and methyl p-toluate in the liquid phase, subsequent esterification of the thus-formed acids, and separation of the thus-produced esters, which comprises treating said high-boiling by-products with methanol at an elevated temperature and then separating the resultant product rich in dimethyl terephthalate by distillation with the addition of a carrier gas or a carrier vapor.