Effect of Gas Permeation Temperature and Annealing Procedure on the Performance of Binary and Ternary Mixed Matrix Membranes of Polyethersulfone, SAPO-34, and 2-Hydroxy 5-Methyl Aniline

摘要

This study investigated the effect of annealing time and temperature on gas separation performance of mixed matrix membranes (MMMs) prepared from polyethersulfone (PES), SAPO-34, and 2-hydroxy 5-methyl aniline (HMA). A postannealing period at 120℃ for a week extensively increased the reproducibility and stability of MMMs, but for pure PES membranes no postannealing was necessary for stable and reproducible performance. The effect of operation temperature was also investigated. The permeabilities of H_2, CO_2, and CH_4 increased with increasing permeation temperature from 35℃ to 120℃, yet CO_2/CH_4 and H_2/CH_4 selectivities decreased. PES/SAPO-34/HMA ternary and PES/SAPO-34 binary MMMs exhibited the highest ideal selectivity and permeability values at all temperatures, respectively. For H_2/CO_2 pair, when temperature increased from 35℃ to 120℃, selectivity increased from 3.2 to 4.6 and H_2 permeability increased from 8 to 26.5 Barrer for ternary MMM, demonstrating the advantage of using this membrane at high temperatures. The activation energies were in the order of CH_4>H_2>CO_2 for all membranes. PES/ SAPO-34/HMA membrane had activation energies higher than that of PES/SAPO-34 membrane, suggesting that HMA acts as a compatibilizer between the two phases.