Novel Zeolite-polyurethane membrane for environmental applications and gas separations

Robert Gordon University., School of Engineering, Aberdeen, UK

^a Corresponding author : e.gobina@rgu.ac.uk

Received: 27 October 2016
Accepted: 15 June 2017

Abstract

This research work investigates the effect of polyurethane polymer on the separation of CO₂, CH₄ and C₃H₈ through a zeolite/polyurethane mixed matrix membrane. A methodology based on the modification of porous ceramic inorganic support with the aim to achieve high selectivity for the hydrocarbons has been developed. Polyurethane-zeolite nanoparticles were prepared by combined blending and casting method. The physical properties of the zeolite/polyurethane mixed matrix membrane were investigated by Scanning Electron Microscope (SEM), Fourier Transform Infra-Red spectroscopy (FTIR) and Nitrogen physisorption (BET). These confirmed the homogenous and nanoscale distribution of zeolite particles in the polyurethane-zeolite membrane. The Nitrogen physisorption measurements showed the hysteresis isotherm of the membrane corresponding to type IV and V that is indicative of a mesoporous membrane. The surface area and the pore size determined using the Barrett, Joyner, Halenda (BJH) desorption method showed a pore diameter of 3.320 nm, a pore volume of 0.31ccg^-1 and surface area of 43.583 m² g^-1. Single gas permeation tests were carried out at a pressure range of 0.01 to 0.1 MPa. The membrane showed the permeance of CH₄ to be in the range of 5.189 × 10^-7 to 1.78 × 10^-5 mol s^-1 m^-2 Pa^-1 and a CH₄/C₃H₈ selectivity of 3.5 at 293 K. On the basis of the results obtained it can be concluded that for the recovery of volatile organic compounds the addition of polyurethane polymer to the zeolite membrane did not increase the performance of the membrane.