Poly ether block amide (PEBA) incorporated with zeolite 13X nanoporous was deposited onto a PSf/PE layer. The fabricated Mixed Matrix Composite Membranes (MMCMs) were weighed up by XRD, SEM, FTIR and AFM analysis. The influence of PEBA concentration, number of coated layers, zeolite loading, PDMS cover layer and a set of conditions for operating a particular process on the gas separation performance of the fabricated membranes were specified through pure gases permeability examination. The best CO2 permeability and CO2/N-2 and CO2/CH4 selectivity for the MMCM loaded with 1 wt% zeolite 13X showed an increase in 200%, 1030% and 3633% compared to the neat membrane. CO2/N-2 and CO2/CH4 selectivity increased 153% and 18.24%, after coating a PDMS cover layer on the PEBA-zeolite (1%)/PSf/PE, respectively. Molecular dynamics (MD) and Grand Canonical Monte Carlo (GCMC) have been performed to reckon the influence of PEBA and zeolite 13X contents on gas separation and thermodynamic properties. Four different Neat and MMMs were constructed in simulation part regarding the incorporation of 0, 0.5, 1 and 2 wt% of zeolite nano-fillers. Fractional free volume (FFV), Density, X-ray diffraction (XRD) and radial distribution function (RDF) were performed to understand the nanostructure properties of the membranes. Having used three different gases (N-2, CO2 and CH4), the permeability and selectivity of constructed membranes have been studied. (C) 2018 Elsevier Ltd. All rights reserved.