PVA-based Pervaporation Membranes for Separation of Water-Alcohol Solutions: A Review

Dehydration of alcohols has attracted a great deal of attention owing to its wide application in several medical, pharmaceutical and chemical industries. High separation efficiency, low energy consumption, simplicity and minimum contamination are the main characteristics making pervaporation (PV) a promising method in the area of alcohol dehydration to provide extremely pure alcohols. Due to their high selectivity and processability, polymers are the main materials for PV membranes. Poly(vinyl alcohol) (PVA) is the most commonly used polymer because of its desired hydrophilicity, flexibility, good film-forming ability and low cost. However, excessive swelling is the main challenge in fabrication of PVA membranes for dehydration application; to overcome this disadvantage, various attempts have been made to modify PVA membranes for separation of water and alcohols. In this paper, various modifications and developments performed to improve the PV performance of PVA-based membranes for separation of water and alcohols are reviewed.