Preparation of porous cellulose acetate membranes by supercritical CO2 phase inversion process

摘要

Supercritical carbon dioxide (SC-CO2), with its distinctive properties, has been attracting more and more attention in the preparation of membranes. In present study, porous cellulose acetate (CA) membranes had been prepared from the CA-acetone casting solution. Effects of polymer concentration, pressure and temperature of SC-CO2 on the water permeation flux of CA membranes were investigated. Experimental results illustrated that the water permeation flux reduced from 23.38 to 0.9 L/m 2 ·min as the polymer concentration increased from 10wt.% to 20wt.%. The water permeation flux increased from 2.04 to 27.11 L/m 2 ·min with the pressure increasing from 8MPa to 15MPa, however, it decreased when the pressure was over 15MPa. It was found that the polymer concentration and pressure of CO2 had significant influences than temperature of CO2 on the water permeation flux of membrane.