(401ao) The Effects of SiO2 and Zeolite 4A/SiO2 on the Transport Behavior of CO2 and CH4 through Polydimethylsiloxane Nanocomposite Membranes

Authors: 
Ogbole, E., North Carolina A&T State University
Lou, J., North Carolina A&T State University
Ilias, S., North Carolina A&T State University

The Effects of SiO2 and Zeolite 4A/SiO2 on the
Transport Behavior of
CO2
and CH4
through Polydimethylsiloxane
Nanocomposite Membranes

Abstract

Emmanuel O. Ogbole, Jianzhong Lou,
Shamsuddin Ilias

Polymeric membrane-based gas separation provides
energy-efficient unit operation in the process  industry. Polydimethylsiloxane (PDMS) is one of the common polymers used for
developing mixed matrix membranes (MMMs) for gas separation as it offers one of the highest
permeability coefficients for a wide range of gas species, modest selectivity, good
material compatibility with inorganic materials, etc.  Single-filler and double-fillers mixed matrix
membranes were prepared with polydimethylsiloxane (PDMS) and different weight
percent of SiO2 and zeolite 4A/SiO2. The effects of the
single filler (SiO2) and double-fillers (zeolite 4A/SiO2)
on the transport behaviors of CO2 and CH4 through the
nanocomposite membranes were investigated. Permeability of CO2 and
CH4 through the neat PDMS membrane and the PDMS mixed matrix
membranes (MMMs) were experimentally measured. CO2 andCH4
permeability were theoretically predicted using Maxwell model. Scanning
electron microscopy (SEM) images and visual
observation showed that SiO2 enhanced
the uniform dispersion of zeolite 4A in the double-filler-PDMS membrane. The
incorporation of SiO2 nanoparticles and
zeolite 4A/SiO2 disrupted the PDMS polymer chains packing
arrangement; thereby, altering the performance of MMMs and the transport
behavior of the gases in the single filler (SiO2-PDMS) MMMs
and double filler (zeolite 4A/SiO2-PDMS). The experimental permeability
measurements of CO2 and CH4 through the (SiO2-PDMS)
MMMs showed a measure of deviation from the theoretical model. The 2.5wt%
zeolite 4A/2.5wt%SiO2-PDMS MMM exhibited significant average CO2/CH4
selectivity improvement over the neat membrane and other MMMs from 3.09 to 4.89.