Isophorone process

Method of making isophorone comprising conducting an aldol condensation of acetone in the vapor phase in the presence of an aldol condensation catalyst at a temperature between about 225.degree. C. to about 325.degree. C. to obtain a reaction product in which at least about 10% of the acetone is converted, removing unreacted acetone in an acetone removal zone, removing free water from the reaction product, removing mesityloxide and water in a mesityloxide removal zone, thereafter removing beta isophorone and mesitylene from said reaction product in a beta isophorone and mesitylene removal zone, and purifying the remaining reaction product to obtain an end product of at least 99% purity.