Abstract
AEI–type AlPO–18 zeolite membranes were prepared on macroporous mullite and two–layer α– Al2O3 tubes with less expensive N, N–diisopropylethylamine (DIPEA) as a single template. The obtained membranes by single DIPEA template showed both high CO2/CH4 and N2/CH4 perm–selectivities and fluxes. The membrane prepared on two–layer α– Al2O3 support showed a CO2 single gas permeance as high as 4.2 × 10–6 mol m–2 s–1 Pa–1 with the perm–selectivity of 90 for CO2/CH4 at 298 K and 0.11 MPa. Besides, a compatible N2/CH4 perm–selectivity of 8.1with N2 single gas permeance of 1.5 × 10–7 mol m–2 s–1 Pa–1 at 298 K and 0.11 MPa was obtained from the membrane prepared on macroporous mullite support. Although a few of AFI type AlPO–5 impurities were formed on the surface of those AlPO–18 zeolite membranes, the AFI impurities didn’t lower the gas permeation performance.
