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

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).