Pervaporation separation of toluene/alcohol mixtures using silicalite zeolite embedded chitosan mixed matrix membranes

摘要

Mixed matrix membranes (MMMs) of chitosan were prepared by incorporating silicalite zeolite particles in 5 and 10 wt.% with respect to weight of chitosan polymer to improve their pervaporation (PV) separation characteristics over that of pristine chitosan membrane for toluene/methanol and toluene/ethanol feeds in compositions of 10—40 wt.% of toluene at 30 °C. The membranes were crosslinked with glutaraldehyde (GA), which was confirmed by Fourier transform infrared spectroscopy (FITR) and ion exchange capacity (IEC) measurements. X-ray diffraction (X-RD) and scanning electron microscopic (SEM) studies were performed to understand membrane morphology. Toluene permeated preferentially with a selectivity of 264 and fluxes of 0.019-0.027 kg/m~2 h for toluene/methanol mixture. Selectivity of 301 with fluxes ranging from 0.019 to 0.026 kg/m~2 h was observed for toluene/ethanol mixtures. Flux increased, while selectivity decreased with increasing toluene content of the feeds. An increase in silicalite content of the MMMs gave increased PV performances.