Abstract
The details of a method of preparing anodic aluminum oxide membranes are presented. The porous oxide layer consists of close-packed cells of oxide, hexagonal in shape, each of which contains a single pore formed perpendicularly to the surface of the aluminum substrate. This special structural feature is essentially important for ultrafiltration and gas separation. The rejection characteristics are examined, using aqueous and nonaqueous solutions of macromolecules. The permeability of gases is also examined at different temperatures. The flow of gases is explained by the Knudsen regime alone.
