Preparation and characterization of SAPO-34 – Matrimid® 5218 mixed matrix membranes for CO2/CH4 separation

Different SAPO-34 zeolite loaded Matrimid® 5218 mixed matrix membranes (MMMs) were prepared by solution casting method and characterized using XRD and SEM analysis. Findings showed that semi crystalline neat polymer becomes more crystalline after thermal treatment at higher temperatures close to Matrimid® 5218 glass transition temperature. Furthermore, incorporation of crystalline filler particles of SAPO-34 zeolite resulted in more and more crystallinity of the MMMs. SEM images also exhibited acceptable contacts between the filler particles and the polymer chains. Permeation measurement showed that CO2 permeabilities and CO2/CH4 selectivities of the MMM with 20 wt% loading of SAPO-34 zeolite particles up to 6.9 (Barrer) and 67, respectively. This can be attributed to size discrimination of SAPO-34 pores that falls between CO2 and CH4 kinetic diameters.

► Fine crystalline SAPO-34 zeolite powder was successfully synthesized. ► Different SAPO-34 zeolite loaded Matrimid® 5218 mixed matrix membranes (MMMs) were prepared by solution casting method. ► SAPO-34 zeolite loaded Matrimid® 5218 (MMMs) were characterized using XRD and SEM analysis, and permeation measurements.