ECTFE membrane preparation for recovery of humidified gas streams using membrane condenser

Abstract

Polymeric flat membranes, using Ethylene–Chlorotrifluoroethylene copolymer (ECTFE), have been made by Thermal Induced Phase Inversion (TIPS). The non-toxic solvent glycerol triacetate (GTA) has been used as solvent. The morphology of the membranes has been analyzed by scanning electron microscopy (SEM). Asymmetric microporous sponge-like membranes have been produced and their properties in terms of contact angle, mechanical properties, pore size and porosity have been compared with the commercial PVDF hollow-fibers membranes. Both types of membranes have been tested using a membrane condenser, varying the feed temperature and feed flow rate, for the selective recovery of water from gaseous streams. The data obtained have been also supported by a simulation study of the process. The results showed that in both type of polymers used, the percentage of water recovered was similar, between 35% and 55%, much higher than the amount of 20% needed to make the plant self-sufficient. The obtained results and the outstanding chemical resistance properties suggested that the ECTFE flat membranes are very promising candidates for being employed in a membrane condenser, which is a new membrane based operation for water recovery from gaseous waste streams (i.e. flue gas).