OPTIMISED LIQUID-PHASE OXIDATION Russian patent published in 2010 - IPC C07C51/265 

FIELD: chemistry.

SUBSTANCE: invention relates to the process of liquid-phase catalytic oxidation of paraxylene to obtain terephthalic acid. Material containing paraxylene is fed into the reaction zone of a bubble column reactor. At least 25 wt % paraxylene enters the reaction zone in one or more sections lying at least 0.05 D from the walls of the column, where D is maximum diametre of the reaction zone. Oxidation of paraxylene to form crude terephthalic acid takes place in the liquid phase of a three-phase reaction medium in which amount of solid substances is kept in the interval from 5 to 40 wt % averaged on time and volume. In the second reactor there is oxidation of crude terephthalic acid to obtain cleaner terephthalic acid.

EFFECT: increased efficiency and cost-effectiveness of the process.

33 cl, 36 dwg, 4 tbl, 2 ex