Sol-gel derived inorganic/organic hybrid separation membrane

Organic/inorganic hybrid separation membranes have been prepared on porous alpha -Al2O3 substrates (pore size, 1-10 mum). The effects of sol synthesis conditions, such as reaction temperature, solvent pH, sol viscosity, n(PTMOS)/n(TEOS) and n(H2O)/n(alkoxide) ratios, on the layer processing and its performance of the resulted membrane were characterized, and an optimum condition of the procedure was achieved. From FTIR spectra, it is found that the crack formation in the membrane is principally related to the structure of the Si-O-Si other than the solvent nature and any other factors. The thickness of the hybrid layer is about 1 similar to2 mum estimated by the SEM image of cross section. The selectivity of O-2/N-2 and CO2/N-2 as well as CO2/O-2 is 2.30, 4.31 and 1.17 respectively, and the permeability is 75.81 X 10(-17), 75.28 X 10(-17) and 72.78 X 10(-17) m(3)(STP).m/(m(2).s.Pa) when the trans-membrane pressure difference is 0.10 MPa and the n(PTMOS)In(TEOS) ratio is equal to 1.16.