OXIDATION SYSTEM WITH SECONDARY REACTOR FOR SIDE STREAM Russian patent published in 2016 - IPC C07C51/265 C07C63/26 B01J8/22 B01J10/00 

FIELD: chemistry.

SUBSTANCE: invention relates to improved system for production of terephthalic acid by contact of paraxylene-containing suspension with gas-phase air-containing oxidant, with said system including primary oxidation reactor, which includes first suspension output; and secondary oxidation reactor, which includes suspension input and second suspension output, in which said suspension input is downstream in hydraulic connection with said first suspension output; in which said secondary oxidation reactor represents secondary reaction zone, which has maximal length Ls and maximal diameter Ds, with said secondary reaction zone having ratio Ls:Ds in the range from 14:1 to 28:1, in which distance from said input from the bottom of said secondary reaction zone is in the interval from 0.3 Ls to 0.9 Ls; with said primary oxidation reactor representing bubble column reactor, and where said secondary oxidation reactor represents bubble column reactor; with said secondary oxidation reactor containing at least one normally lower oxidant input and at least one normally upper oxidant input. The invention also relates to method for production of terephthalic acid composition, with said method including: (a) supply of first multiphase reaction medium, containing compound to be oxidised to oxidation in primary reaction zone, located in primary oxidation reactor, which results in obtaining first suspension, with compound to be oxidised containing paraxylene; and (b) contact of at least part of said first suspension with gas-phase oxidiser in secondary reaction zone, which is located in secondary oxidation reactor, which results in obtaining second suspension, with gas-phase oxidiser containing air, where first part of said gas-phase oxidiser is introduced into said second reaction zone through normally upper oxidant input, while second part of said gas-phase oxidant is introduced through normally lower oxidant input, with said secondary reaction zone having maximal length Ls and maximal diameter Ds, where said secondary reaction zone having ratio Ls:Ds in the range from 14:1 to 28:1, in which at least part of said first suspension is supplied into said secondary reaction zone in the area of suspension input at the distance from the bottom of said secondary reaction zone in the interval from 0.3 Ls to 0.9 Ls; and where said primary oxidation reactor represents bubble column reactor, and secondary oxidation reactor represents bubble column reactor.

EFFECT: device and method can contribute to reduction of oxygen content in the entire additional oxidation reactor.

13 cl, 6 dwg