Formation and characterization of mixed matrix composite materials for efficient energy gas separation

• Main Authors: Wan Abdul Rahman , Wan Aizan, Ismail, Ahmad Fauzi
• Format: Monograph
• Language: English
• Published: Universiti Teknologi Malaysia 2005
• Subjects: TP Chemical technology
• Online Access: http://eprints.utm.my/id/eprint/2830/1/75126.pdf; http://eprints.utm.my/id/eprint/2830/

Blend of high performance molecular sieving particles in polymers, known as mixed matrix membrane, offer the potential to combine the excellent gas separation properties of molecular sieving materials with the processability of the polymers (Wahab et al., 2004). The current commercial glassy polymer could provide the commercially acceptable minimum performance of matrix phase compares to rubbery polymer. The objective of this research is to develop a new mixed matrix membrane for O2 /N2 gas separation. Mixed matrix membrane was prepared in our laboratory to study the effect of incorporating molecular sieve particles into blends of polymers matrix. Blends of Polyethersulfone (PES) and Matrimid® 5218 (PI) were prepared by a solution casting method at three different compositions, which are 20/80, 50/50 and 80/20 wt ratio of PI/PES. Zeolite 4A was used as the dispersed particles and its amount was varied between 10% to 50% zeolite loading. Effect of different type of zeolite was also studied using zeolite 3A and 5A. The final membrane was annealed and further dried in vacuum oven at temperature of 150 oC to 250 oC. The gas separation properties of the membrane and N2 as the test gases, at room temperature and were examined using pure gas O2 upstream pressure was varied between 1 atm to 3 atm. The membrane structure was characterized using four different methods which are FTIR, DSC, TGA and SEM. FTIR results showed that some peak shifted and new peaks occurred to the new develop mixed matrix membrane. DSC scanning showed that one Tg is achieved with all the membrane. This confirms that both polymers and zeolite are compatible with each other. TGA analysis showed that by increasing the zeolite loading, it helps to stabilize the thermal degradation of the mixed matrix membrane. Lastly, SEM picture showed that with increasing zeolite loading, it tends to create more voids between the polymer matrix and zeolite surface. These voids create additional path for the gas molecule to pass through instead of observing the molecular sieve effect of the zeolite, thus will increase the gas permeability, while selectivity decrease.