Patent ID: 8617291

Claim:
A method of preparing a supported gas separation membrane, comprising: a. preparing crystalline seeds from a synthesis mixture, comprising a first aluminum source, a first phosphorous source, a first silicon source, at least one a first organic templating agent and water, wherein the first aluminum source of the synthesis mixture is aluminum isopropoxide that is less pure than 99.99% aluminum isopropoxide; b. applying the seeds to a porous support to produce a seeded porous support; c. contacting the seeded porous support with a synthesis gel, comprising a second aluminum source, a second phosphorous source, a second silicon source, a second templating agent, and water wherein the second aluminum source of the synthesis gel is a very pure aluminum source comprising greater than 99.99% aluminum isopropoxide, under hydrothermal synthesis conditions to produce a coated porous support; and d. calcining the coated porous support.