Patent ID: 6160159
Filing Date: 2000-12-12
Classification: C07C

Abstract:
A process for the production of dimethyl terephthalate comprising the steps of:(a) oxidizing at a first selected temperature a feedstock selected from the group consisting of p-tolualdehyde and p-tolualdehyde/p-xylene containing feedstocks with an oxygen containing fluid to produce p-toluic acid;(b) carrying out a step selected from the group consisting of:(1) esterifying the product of step (a) with methanol to form methyl p-toluate and oxidizing at a second selected temperature the methyl p-toluate with an oxygen containing fluid to form monomethyl terephthalate, and(2) oxidizing the product of step (a) with an oxygen containing fluid to form terephthalic acid;(c) esterifying the product of step (b) with methanol to form a product containing dimethyl terephthalate; and(d) separating the dimethyl terephthalate from the product of step (c),wherein the oxidations are carried out in the absence of any bromine compound.