(160c) Mixed-Matrix Membranes Containing Engineered Nanoporous Materials for Biogas Purification
Among various porous materials, metal-organic frameworks which comprise metal center and organic linkers to form three-dimensional porous structure have attracted vast research interests in the recent years as potential fillers for mixed-matrix membrane fabrication owing to their large pore volumes and tunable functionalities. In this work, a submicron-sized Zn(pyrz)2(SiF)6 metal-organic framework crystal possessing both an optimum pore size for selective CO2 permeation and a strong affinity for CO2 molecule was synthesized and incorporated into various polymer membranes to design mixed-matrix membranes for biogas upgrading. CO2/CH4 mixture gas permeation tests revealed that the separation properties of mixed-matrix membranes, especially selectivities, were significantly improved compared to those of pure polymeric membrane owing to the selective CO2 uptake and transport in the metal-organic framework crystals.
Recently, our research group have developed hierarchical mesoporous Ca-A zeolites with amine-appended mesoporous domain for application in post-combustion CO2 capture. Owing to the contributions of both the active sites in Ca-A zeolites and the amine groups in mesoporous surfaces, the material exhibited an excellent CO2 uptake property even at low CO2 partial pressure. Moving forward, amine-appended hierarchical Ca-A was employed as a filler for mixed-matrix membranes to improve CO2 selectivity. Gas permeation testing revealed that the amine-appended hierarchical Ca-A is highly efficient in enhancing CO2/CH4 selectivity of polymeric membranes.
1. H. Gong, T. H. Nguyen, R. Wang, T. H. Bae, Separations of binary mixtures of CO2/CH4 and CO2/N2 with mixed matrix membranes containing Zn(pyrz)2(SiF)6 metal-organic framework, J. Membr. Sci. 2015, 495, 169-175
2. T. H. Nguyen, S. Kim, M. Yoon, T. H. Bae, Hierarchical LTA zeolites with amine-functionalized mesoporous domain for carbon dioxide capture, ChemSusChem, 2016, DOI:10.1002/cssc.201600004
3. T. H. Nguyen, H. Gong, S. S. Lee, T. H. Bae, Amine-appended hierarchical Ca-A zeolite for enhancing CO2/CH4 selectivity of mixed-matrix membranes, submitted