The application of dry gel synthesis procedures in the preparation of zeolite A membranes on a-alumina supports has been explored. With the dry gel method, the amount of initial gel applied to the support as well as the dilution of the initial gel may be used to directly control the amount of zeolite formed, and thus the thickness of the membrane. The results of these experiments show that the combination of dilute aqueous initial gel (1.35SiO(2):Al2O3:5Na(2)O:1000H(2)O) with low temperature drying (298 K) yielded zeolite A membranes with small uniform crystals of size similar to 0.2 mum. These membranes were characterized by single gas permeation and for gas separations with a mixture of butanes and neo-pentane. Neo-pentane, iso-butane and n-butane could not be separated directly. However, neo-pentane was completely excluded from the pore system by C6 adsorption (hexane or cyclohexane) prior to the permeation test and an n-butane/iso-butane separation factor of 2.3 was obtained.