A PROCESS FOR THE PRODUCTION OF ETHYLENICALLY UNSATURATED CARBOXYLIC ACIDS OR ESTERS AND A CATALYST THEREFOR

摘要

A method of producing an ethylenically unsaturated typically an a ß ethylenically unsaturated carboxylic acid or ester is described. The method comprises the steps of contacting formaldehyde or a source of formaldehyde with a carboxylic acid or ester in the presence of a catalyst and optionally in the presence of an alcohol. The catalyst comprises barium phosphate leaf or plate shaped/like crystals or a source thereof.A catalyst system is also described. The catalyst system comprises a crystalline barium phosphate catalyst and optionally a catalyst support.