Fabrication of mixed matrix membranes containing TiO2 nanoparticles in Pebax 1657 as a copolymer on an ultra-porous PVC support

•Mixed matrix membranes containing TiO2 nanoparticles in Pebax 1657 on an ultraporous PVC support were successfully fabricated.•The results confirmed a good interfacial adhesion between polymer and nanofillers.•Membranes showed the best performance at TiO2 loading concentration of 3% at 40 and 15 bar.

Mixed Matrix Membrane (MMM) recently has shown a great potential for separation of CO2 from CH4 as the main part of a gas sweetening process for natural gas treatment. The main objective of this study is to develop novel nanocomposite membranes of TiO2 as inorganic nano-filler incorporated into poly (ether-b-amide) Pebax 1657 as the polymer matrix. Considerable improvement of permeation and selectivity was achieved for synthesized membranes for separation of CO2 and CH4 over a range of operating variables. The scanning electron microscopy (SEM) was used to characterize nanocomposite membranes which images showed high degree of agglomeration in high loadings of TiO2 in polymer matrix. Defect free organic/inorganic membranes showed the best performance at TiO2 loading concentration of 3% at  30 °C and 15 bar. The CO2 permeability increased from 129 Barrer for Pebax to 167 Barrer and a remarkable enhancement in the related CO2/CH4 selectivity was observed from 37 to 51.