Chemical Engineering Journal, Vol.308, 27-39, 2017
Synthesis and characterization of thin film nanocomposite membranes incorporated with surface functionalized Silicon nanoparticles for improved water vapor permeation performance
The present work demonstrates the fabrication of novel thin film nanocomposite membranes incorporating surface functionalized Silicon nanoparticles (average size 15-20 nm) for removal of water vapor from nitrogen gas. Silicon nanoparticles were synthesized using the inductively coupled plasma (ICP) technique. The nanoparticles were dispersed in deionized water to introduce hydroxyl functional groups on the surface. The surface functionalization was confirmed by infrared spectroscopy. The effect of nano-Si concentration on the water vapor permeation properties of the TFN membranes was investigated in detail. The hydroxyl functional groups resulted in significant improvement of surface hydrophilicity and roughness of the nanocomposite membranes which in turn enhanced the water solubilization. The small size of nanoparticles permitted extensive interaction between the nanoparticles and the thin film polyamide layer. Increase in the nano-Si concentration resulted in improvement of water vapor permeance and selectivity till 0.5 w/w%, above which the selectivity decreased because of the interference in interfacial polymerization reaction due to the dilution of aqueous phase monomer and high loading of nanoparticles. Water vapor permeance in excess of 2200 GPU with vapor/N-2 selectivity of 501 was obtained when the nano-Si loading was 0.5 wiw%. The introduction of nano-Si in the polyamide membrane improved the stability of the nanocomposite membrane such that it slightly resisted the decrease in water vapor permeance with operating temperature. (C) 2016 Elsevier B.V. All rights reserved.
Keywords:Interfacial polymerization;Thin film nanocomposite membranes;Silicon nanoparticles;Hydrophilicity;Water vapor transport