The present invention provides methods for making improved zeolite and crystalline silicoaluminophosphate (SAPO) membranes, in particular SAPO-34 membranes, on a porous support through improved removal of the organic structure-directing templating agent. A calcining step is performed in an oxygen free atmosphere, such as under a vacuum or inert gas, to remove the organic templating agent. By removing the templating agent in the absence of oxygen, the calcination step can remove a greater amount of the templating agent than comparable template removal steps conducted in the presence of oxygen and the calcination step can be conducted at significantly lower temperatures. The membranes of the present invention provide increased permeance while maintaining comparable selectivity for gas separations, particularly carbon dioxide (CO2) and methane (CH4) separations and separations at high temperatures.