Patent ID: 6514899
Filing Date: 2003-02-04
Classification: B01J,C01B,C07C,C10G,Y02P

Abstract:
A method for forming a silicoaluminophosphate (SAPO) molecular sieve comprising:providing a source of a silicon-containing composition; providing a source of an aluminum-containing composition; providing a source of a phosphorus-containing composition; providing a template; forming a reaction mixture sufficient to form a SAPO molecular sieve from said source of a silicon-containing composition, said source of an aluminum-containing composition, said source of a phosphorus-containing composition, and said template, said reaction mixture having a first pH; determining a pH increase in said reaction mixture such that said reaction mixture has a second pH higher than said first pH; adding, after said determining said pH increase, an acid to said reaction mixture to adjust said second pH to from said first pH plus about one pH unit to said first pH minus about one pH unit; and crystallizing said SAPO from said reaction mixture.