Removal of aldehyde in acetic acid production process

摘要

The present technology discloses processes for producing carboxylic acid. In some embodiments, the processes include contacting methanol and carbon monoxide in the presence of a liquid reaction medium under carbonylation conditions sufficient to form a carbonylation product, including acetic acid and acetaldehyde. The liquid reaction medium may include a carbonylation catalyst selected from rhodium catalysts, iridium catalysts and palladium catalysts; and water in a water concentration in a range of 1 wt. % to 14 wt. % based on the total weight of the liquid reaction medium. In certain embodiments, the processes comprise contacting at least a portion of the carbonylation product or a derivative thereof with a micro-porous material such as a silicoaluminophosphate (SAPO) to selectively convert at least a portion of the acetaldehyde to crotonaldehyde.