A STUDY OF POLYDIMETHYLSILOXANE AROMATIC POLYAMIDE LAMINATED MEMBRANES FOR SEPARATION OF ACETIC-ACID WATER MIXTURES BY PERVAPORATION PROCESS

Separation of acetic acid/water mixtures by pervaporation was attempte d over a range of compositions using polydimethylsiloxane (PDMS). arom atic polyamide (PA), and laminated polydimethylsiloxane-aromatic polya mide membranes. PDMS membranes are hydrophobic and acetic acid selecti ve. whereas PA membranes are hydrophilic and water selective. When PDM S and PA membranes were laminated, with PDMS on the top side and in co ntact with the feed, water selectivity of the bottom PA membrane was i ntensified. On the other hand. when the PA membrane was on the top sid e and in contact with the feed. the selectivity was lowered.