A Mixed Matrix Membrane of Poly (4-methyl-1-pentyne) Filled with MIL 53 Particles and Its Application in Carbon Dioxide and Nitrogen Separation

The performance of poly (4-metyl-1-pentyne) as mixed matrix membrane (MMM) mixed with MIL 53 particles was studied to separate mixtures of carbon dioxide and nitrogen. MIL 53 particles was added to the polymer matrix with 10, 20 and 30 weight percentages. The adsorption of CO₂ and N₂ gases by MIL 53 was evaluated and the adsorption data was analyzed by Langmuir equation. Structure and thermal/mechanical properties of prepared membranes were characterized by means of FTIR, SEM, TGA and elongation test. Moreover, the gas permeation properties of membranes were studied by measuring the permeation of pure CO₂ and N₂. Furthermore, for accurate understanding of the gas permeation properties of the membranes, diffusion and solution coefficient of gases in neat membrane and MMMs were calculated using modified time-lag method. The results from TGA analysis showed that the degradation temperature of MMMs was enhanced and increased to 348ºC for membrane containing 30 wt% of MIL 53. The SEM images also illustrated a relatively uniform dispersion of particles with proper polymer/filler interfaces in the polymer matrix. The gas permeation results revealed that the permeability of both gases (especially CO₂) increased with increasing MIL 53 loading, in which the permeability of CO₂ increased from 98.74 Barrer in neat membrane to 217.65 Barrer in MMM containing 30 wt% filler. Moreover, calculation of CO₂/N₂ selectivity depicted that the selectivity enhanced from 16.66 to 22.70. Finally, the performance of MMMs was compared with Robeson’s upper bound in CO₂/N₂ separation and results showed that the MMM having 30 wt% of MIL 53 took over the Robeson bound.