Methanol conversion process with catalyst containing a hydrothermally treated sapo molecular sieve

摘要

A silicoaluminophosphate molecular sieve is hydrothermally treated at temperatures in excess of about 700C for periods sufficient to destroy a large proportion of their acid sites while retaining at least 80 percent of their crystallinity to form a catalyst for converting methanol to lower olefins. This catalyst shows increased catalyst life, increased selectivity for C2 - C3 olefins and decreased selectivity for paraffin production relative to the untreated molecular sieve.