Processes for producing terephthalic acid

摘要

Processes for producing terephthalic acid are disclosed, the processes including a step of combining in a reaction medium para-xylene, a solvent comprising water and a saturated organic acid having from 2-4 carbon atoms, and an oxygen-containing gas, at a temperature for example from about 145° C. to about 175° C., in the presence of a catalyst composition comprising cobalt, manganese, zirconium, and bromine, wherein the zirconium is present in the reaction medium in an amount, for example, from 1 ppm to 50 ppm with respect to the weight of the liquid in the reaction medium.

主权项

1. A process for producing terephthalic acid, the process comprising combining in a reaction medium para-xylene, a solvent comprising water and a saturated organic acid having from 2-4 carbon atoms, and an oxygen-containing gas, at a temperature from about 145° C. to about 175° C., with an overhead pressure above the reaction medium of about 1 to about 40 bar gauge (barg), in the presence of a catalyst composition comprising cobalt, manganese, zirconium, and bromine, wherein the zirconium is present in the reaction medium in an amount from about 1 ppm to 50 ppm and wherein the total amount of zirconium, nickel, chromium, and cerium is no more than 50 ppm, with respect to the weight of the liquid in the reaction medium.