PROCESS FOR THE PREPARATION OF TEREPHTHALIC DIALDEHYDE, ISOPHTHALIC DIALDEHYDE AND PHTHALIC DIALDEHYDE

摘要

A process for the preparation of a terephthalic, isophthalic or phthalic dialdehyde is described by dehydrogenation of the corresponding xylylene glycol in the vapor phase at 250 DEG to 500 DEG C. The process is carried out in the presence of oxygen, water vapor and a dehydrogenation catalyst, suitably a silver dehydrogenation catalyst.