Surface Modification of AMH-3 for Development of Mixed Matrix Membranes

AMH-3 layered silicate is chosen for this study as its 3D structure with crystallographic pore size of 3.4 Å makes it an attractive material for gas separation applications. AMH-3 layered silicate was synthesized via hydrothermal synthesis method and then functionalized using octyl(methyl)dimethoxysilane to enhance its hydrophobicity for good adhesion and dispersion in mixed matrix membrane. In this work, high permeability polysulfone (PSf) was incorporated with AMH-3 for fabrication of mixed matrix membranes. The critical polymer concentration of PSf was studied to suppress the formation of macrovoids in mixed matrix membranes. Flat sheet PSf/AMH-3 membranes were then prepared by dry/wet phase inversion technique with different loadings of AMH-3 in PSf matrix. The synthesized AMH-3 layered silicate is verified by FT-IR and XRD analysis. Structural changes of AMH-3 after functionalization are observed in FT-IR, XRD and SAP analysis. Functionalized AMH-3 shows higher surface area and reduced pore size. The MMMs of pristine and functionalized AMH-3 have similar surface and cross-sectional morphologies, showing good distribution and dispersion of inorganic filler. AMH-3 shows improved hydrophobicity after functionalization, resulting in better adhesion and compatibility with polysulfone