The invention is directed to a method for making a silicoaluminophosphate
(SAPO) molecular sieve from a reaction mixture comprising components
present in amounts sufficient to form the SAPO, the reaction mixture
having a first pH. The method comprises the steps of: adding an acid to
the reaction mixture after the reaction mixture undergoes a change in pH
from the first pH; and crystallizing the SAPO from the reaction mixture.
The present invention is also directed to a silicoaluminophosphate
molecular sieve made by this process.
