Characterization of Inorganic Silicalite-1 Membrane to be used for the Separation of Greenhouse Gases

Defect free MFI type silicalite-1 membranes have been fabricated inside tubular TiO2 ceramic supports to be used for the separation of greenhouse gases. In this work, single gas permeance experiments have been conducted. The results of which in conjunction with adsorption isotherms for each gas investigated have been used to calculate the effective diffusivities of N2, CH4, and CO2. The permeances at 22 °C and 1 atm of pressure differential for He, N2, CO2 and CH4, were found to be 4.38 x 10-7, 7.71 x 10-7, 1.35 x 10-6, and 1.64 x 10-6 mol/m2sPa, respectively, giving permeance ratios for the separation of CH4/N2, CO2/N2, and CH4/CO2 equal to 2.13, 1.75, and 1.22 respectively. These permeance ratios are comparable to those found in other studies reported in the literature, whereas the permeances are typically 1 to 2 orders of magnitude greater than those found in the literature at similar conditions.