Separation of Ethanol mixtures by Nanopore HS zeolite membranes

Effects of synthesis parameters on the membrane structure and performance have been investigated for Nanopore Hydroxysodalite (HS) zeolite membranes grown onto seeded mullite supports. Molar composition of the starting gel of HS zeolite membranes was: SiO2/Al2O3=1.0-5.0, Na2O/Al2O3=15-65, and H2O/Al2O3=500-1500. Also, Effects of crystallization time and temperature on the membrane performance were studied. X-ray diffraction (XRD) patterns of the membranes exhibited peaks corresponding to the support and the zeolite. The crystal species were characterized by XRD and morphology of the supports subjected to crystallization was characterized by Scanning electron microscopy (SEM). Separation performance of HS zeolite membranes was studied for water-Ethanol mixtures using pervaporation (PV). The membranes showed good selectivity towards water in the water-Ethanol mixtures. Water permeates faster because of its preferential adsorption into the nano-pores of the hydrophilic zeolite membrane. In PV of water-Ethanol mixtures, the membrane exhibits a hydrophilic behavior, with a high selectivity towards water and a good flux. The best Flux and separation factor of the membranes were 2.05 kg/m2.h and 10000, respectively.

Keywords:

nano , hydroxysodalite , Pervaporation , Ethanol , Zeolite , membrane