Inner-coated highly selective thin film nanocomposite hollow fiber membranes for the mixture gas separation

Polyamide-based thin film nanocomposite (TFN) membranes were prepared by incorporating nanoparticles in an aqueous phase containing m-phenylenediamine (MPD) and an organic phase containing trimesoyl chloride (TMC) by interfacial polymerization (IP) method. The 3-aminopropyltrimethoxy silane grafted mesoporous synthetic hectorite (APTMSH) was synthesized and added in an aqueous monomer solution while the IP. In this work, the TFN layer interfacial compatibility has been enhanced by building the covalent bond between APTMSH and other two monomers by IP method. The coating of the TFN selective layer was done on the inner surface of polysulfone hollow fiber membranes. The interesting results were obtained for the binary mixture gas separation containing water vapor/N-2 and CO2/CH4. Improved gas permeance and selectivity have been obtained using APTMSH-incorporated TFN membranes. The developed TFN membranes have been characterized using several physicochemical methods. The results show that with the addition of APTMSH in MPD solution up to 0.5 w/w% the best water vapor permeance 2485 GPU and CO2 permeance 22.3 GPU were obtained along with water vapor/N-2 selectivity 725.5 and CO2/CH4 selectivity 26.68 respectively through APTMSH@TFN-3 membrane.