A new kind of self supported dual layer mixed matrix membrane was developed in this work using ZIF-8 as inorganic filler in PEBAX-2533 polymer matrix. The developed dual layer flat sheet mixed matrix membrane was characterized to investigate the morphology of organic-based and inorganic-based layer. The gas separation properties of the mixed matrix membranes were tested using single gases CO2, CH4, N-2, and O-2 and a mixture of CO2 and N-2 in dry and humidified conditions. The permeability of all examined gases increased as the inorganic filler content increased in the matrix membranes, and specifically it increased dramatically for CO2 in all cases, single feed gas and dry and humidified mixed gas. The CO2/N-2 selectivity decreased slightly from 33.8 for the pure PEBAX membrane to 32.3 for the mixed matrix membrane with 35% ZIF-8 loading, while more significant drop in CO2/N-2 selectivity was observed in experiments using mixed gases. (C) 2014 Elsevier B.V. All rights reserved