Improving the Gas‐Separation Properties of PVAc‐Zeolite 4A Mixed‐Matrix Membranes through Nano‐Sizing and Silanation of the Zeolite

Abstract

Mixed‐matrix membranes containing synthesised nano‐sized zeolite 4A and PVAc were fabricated to investigate the effect of zeolite loading on membrane morphology, polymer‐filler interaction, thermal stability and gas separation properties. SEM studies revealed that, although the membranes with 40 wt % nano‐sized zeolite particles were distributed uniformly through the polymer matrix without voids, the membranes with 15 wt % zeolite loading showed agglomeration. With increasing zeolite content, the thermal stability improved, the permeability decreased and the selectivity increased. The effect of silanation on dispersion of 15 wt % zeolite 4A nanoparticles through PVAc was investigated by post‐synthesis modification of the zeolite with 3‐Aminopropyl(diethoxy)methylsilane. Modification of the nanoparticles improved their dispersion in PVAc, resulting in higher thermal stability than the corresponding unmodified zeolite membrane. Modification also decreased the rigidity of the membrane. Partial pore blockage of the modified zeolite nanoparticles after silanation caused a further decrease in permeability, compared to the 15 wt % unmodified zeolite membrane.

A Review on Glassy and Rubbery Polymeric Membranes for Natural Gas Purification

“…In another study by Esmaeili et al. 194, zeolite 4A nanoparticles were added to PVAc as the polymer matrix and their different gas separation performances were investigated. The increment in the amount of zeolite nanoparticles from 15 to 40 wt % caused the permeabilities of all the studied gases (CO 2 , H 2 , N 2 , He) to decrease compared with that of the pure PVAc membrane, but increased their selectivities, i.e., CO 2 /N 2 , He/CO 2 , H 2 /N 2 , H 2 /CO 2 .…”

Proton Conductive Membranes from Covalently Cross‐Linked Poly(Acrylate)/Silica Interpenetrating Networks

“…Among different types of fuel cells, proton exchange membrane (PEM) fuel cells have many advantages, such as low operating temperature, long stack life, compactness, low cost, and fast startups. [ 1–3 ] The core component of PEM fuel cells is the membrane electrode assembly, which is composed of a polymer electrolyte membrane confined between two electrodes. Fabricating high‐performance membrane materials is a major challenge for the effective operation of PEM fuel cells, where the materials need to meet requirements including high proton conductivity (PC), low swelling, and high oxidative and hydrolytic stability.…”

“…Sulfonated poly(ether ether ketone)s, poly(arylene ether sulfone)s, poly(sulfones), poly(benzimidazoles), and their derivatives have been studied most intensively. [ 2,5–7 ] For hydrocarbon‐based membranes, a higher degree of sulfonation is necessary in order to achieve high PC, since the acid strength of the sulfonic acid groups in these materials is significantly lower than in perfluorosulfonic acid‐based membranes. [ 8 ] Furthermore, it was observed that the phase separation and thus the formation of proton‐conducting channels in hydrocarbon‐based systems is less pronounced than in Nafion.…”

“…One strategy exploits the incorporation of inorganic fillers into the polymer matrix. [ 2,3,12 ] This is achieved by blending, doping, sol–gel processing, or in situ polymerization methods. Among others, various metal oxides, such as SiO 2 , [ 13,14 ] TiO 2 , [ 15 ] CeO 2 , [ 16 ] or mixed oxides, [ 17 ] have been widely used as membrane modifiers.…”

Improved gas transport properties of polyurethane–urea membranes through incorporating a cadmium‐based metal organic framework

“…Furthermore, the contribution of the nanofillers to MMMs enhances the thermal stability of the membranes without considerable adverse effect on the processability of the membranes . Typical fillers used in these membranes include metal oxides, zeolites, two‐dimensional (2D) nanomaterials, covalent organic frameworks, and metal–organic frameworks (MOFs) . Although it has been observed that separation properties of polymeric membranes improve by adding inorganic fillers, there are still some technical challenges in the selection of proper polymer matrix and inorganic fillers.…”