Production of aromatic carboxylic acids

摘要

Disclosed are processes and systems for the production of aromatic carboxylic acids, such as purified terephthalic acid. The processes result in reduced volatile aromatic monocarboxylic acid contamination throughout various stages of the PTA process when compared to known processes. This permits the various effluent streams to be recycled back to several stages in the production process, which allows for the efficient production of pure PTA at a lower cost.

主权项

1. An aromatic polycarboxylic acid manufacturing process comprising:
a) separating an oxidation reactor vent gas stream into an acetic acid rich stream and a water rich vapor stream, wherein the water rich vapor stream comprises volatile compounds and non-condensable gases, and said separating is performed in a distillation device; b) condensing said water rich vapor stream into a condensate stream and a vapor stream; c) feeding a first portion of said condensate stream to said distillation device and feeding a second portion of said condensate stream to an extraction column; and d) removing at least one aromatic monocarboxylic acid from said second portion of said condensate to form an aromatic monocarboxylic acid stream and a aqueous product stream.