Patent ID: 9701610
Date: 2017-07-11
CPC Classifications: B01J,C07C

Claim:
1. A process comprising the steps of: (A) Contacting in a reaction zone and under dehydration reaction conditions a beta-hydroxy carboxylic acid and/or its ammonium salt with a catalytic amount of a catalyst comprising ammonium bisulfate (ABS) to form a dehydrated carboxylic acid, water and ammonium sulfate (AS), (B) Removing a vapor stream comprising the dehydrated carboxylic acid and water from the reaction zone, (C) Removing a liquid stream comprising AS from the reaction zone, (D) Forwarding the vapor stream to a purification zone in which the dehydrated carboxylic acid is separated from water, (E) Forwarding the liquid stream comprising AS to a thermal conversion zone in which the AS is converted to ABS and ammonia, (F) Optionally, recycling the ABS from step (E) to step (A), (G) Optionally, recovering ammonia from the thermal conversion zone, and (H) Optionally, removing a purge stream comprising ABS and/or AS prior to or at or near the beginning of the thermal conversion zone.