Influence of ZIF-67 Drying Temperatures on the Structure and Properties of PEBAX^® MH-1657/ZIF-67 Mixed Matrix Membranes for Enhanced CO₂/N₂ Separation

This study synthesized mixed matrix membranes (MMMs) using PEBAX^® MH-1657 and ZIF-67 with varying particle concentrations (1, 3, and 5 wt%) to assess permeability and selectivity. ZIF-67 nanoparticles were prepared using the solvothermal method with methanol and characterized. Permeation tests were conducted at 10 and 15 bar using N₂ and CO₂. The analysis revealed ZIF-67 particles with an approximate diameter of 280 nm and confirmed characteristic sodalite peaks. The ideal CO₂/N₂ selectivity reached 67 (CO₂ permeability = 132 ± 3.5 Barrer) at 15 bar. The impact of ZIF-67 varied with pressure and composition; at 10 bar, CO₂/N₂ selectivity decreased compared to pure PEBAX^®; however, at 15 bar, the 1 wt% ZIF-67 membrane exhibited superior selectivity, surpassing Robeson's upper bound. The results indicate that ZIF-67 enhances the permeability and selectivity of PEBAX^®, with superior performance observed at lower concentrations.

Keywords:
Mixed matrix membranes; gas separation; ZIF-67 and PEBAX^® MH-1657