A STUDY OF PORE-SIZE DISTRIBUTION AND MEAN PORE-SIZE ON UNSUPPORTED GAMMA-ALUMINA MEMBRANES PREPARED BY MODIFICATIONS INTRODUCED IN THE ALKOXIDE HYDROLYSIS STEP

Unsupported gamma-alumina membranes were prepared by sol-gel technique using aluminium sec-butoxide as starting material. The effect on the unsupported gamma-Al2O3 microstructure has been studied of the addition to the hydrolysis water of several acids, a cationic exchange resin, and both simultaneously in the hydrolysis step. The pore size distribution, mean pore size and porosity of the gamma-Al2O3 unsupported membranes were evaluated using the N2 adsorption technique. The lowest mean pore size (24 angstrom) and the narrowest pore size distribution were obtained by using both the cationic exchange resin and perchloric acid.