Solid phosphoric acid catalyst

摘要

A solid phosphoric acid catalyst having a total X-ray intensity of at least 30 percent relative to alpha-alumina. The solid phosphoric acid catalyst is produced by crystallizing an amorphous mixture of an acid oxide of phosphorus and a siliceous material at a temperature of from 250 DEG to 450 DEG C. and in the presence of from 3 to 50 mole percent water vapor based upon the total vapor rate to the crystallizing means.