PROCESS FOR PREPARATION OF DIESTERS OF TEREPHTHALIC ACID WITH PUMPING OF THE REACTION MIXTURE Russian patent published in 2018 - IPC C07C67/08 C07C69/82 

FIELD: biochemistry.

SUBSTANCE: present invention relates to process of preparation of a diester of terephthalic acid by reacting terephthalic acid with at least one alcohol, wherein a) terephthalic acid is suspended in an alcohol in a dispersing vessel to form a preliminary suspension, b) pre-suspension from the dispersing vessel is sent to the reactor and subjected to reaction in the presence of an esterification catalyst, c) reaction slurry is withdrawn from the region located between the upper region and the lower region of the reactor, withdrawn reaction slurry is separated, the first stream of the reaction slurry is returned to the upper region of the reactor, and the second stream of the reaction slurry is sent to the lower region of the reactor, and thus the reaction slurry is stirred, d) wherein the withdrawn stream and/or the first stream is passed through a heat exchanger located outside the reactor and heated and e) reaction water in the form of an aqueous alcoholic azeotrope is removed by distillation along with the vapor, the vapors are at least partially condensed, condensate is separated into an aqueous phase and an organic phase, and the organic phase is at least partially recycled to the reaction system.

EFFECT: method allows to achieve complete conversion of terephthalic acid.

14 cl, 2 dwg