Characterization of asymmetric polysulphone membranes for gas separation

J. MARCHESE; C. PAGLIERO

Gas Separation and Purification

Elsevier

Año: 1991 vol. 5 p. 215 - 221

0950-4214

Abstract The mean pore size and surface porosity of the dense skin of polymeric asymmetric membranes were determined by the gas permeability method. When the contribution of the flux of a gas permeating through the dense skin is greater than 10% of the ?slip? flux in the pore, the dense skin thickness can be obtained from the equations developed in the present work. The method was applied to investigate the influence of the parameters involved in the preparation of polysulphone asymmetric membranes by the wet process of phase inversion. Electron microscopy was used to determine the structure and thickness of the dense skin. The results obtained with the microporous membranes synthesized indicate the following trends: pore size increases and surface porosity decreases with (i) increasing temperature of the coagulation bath; (ii) increasing concentration of polymer in the casting solution; and (iii) increasing casting thickness.