PDMS mixed matrix membranes modified by graphene nanosheets for ethanol/water pervaporation

The world has relied on petroleum as an important and indispensable energy source for decades. In recent years, by increasing oil price and global warming, the need for finding other energy sources especially renewable and clean sources such as ethanol become the important challenge. Separation of ethanol/water mixtures through classical separation methods such as distillation is very energy consuming. Membrane process is a new method used by researchers. Among the various membrane techniques, pervaporation (PV) is one of the most attractive methods because it is economical and easy to use. Over the last few decades, different polymers have been used as materials in membrane preparation for PV application. Polydimethylsiloxane (PDMS) is one of the best polymers for the preparation of membranes in separation of organic-organic liquid mixtures Due to its high hydrophobicity. In present work, a nanocomposite ethanol permselective membrane including PDMS polymer filled with GNS (۰.۵ wt%) nanoparticles was synthesized. The membranes were analyzed using FTIR and XRD. The bonding of groups in GNS and membranes was characterized and confirmed using FTIR test. Pervaporation tests indicated better performance in the membrane with ۰.۵% loading of GNS in synthetic ethanol-water solution with ۳۹% increment in ethanol selectivity and ۱۶۰% increment in flux.

Keywords:

Ethanol water separation , pervaporation , PDMS , graphene nanosheets , nanocomposite membrane , membrane process.