Abstract:
Nanocomposite sodalite/ceramic membranes supported on -Al2O3 tubular support were
prepared via the pore-plugging hydrothermal (PPH) synthesis protocol using one interruption and
two interruption steps. In parallel, thin-film membranes were prepared via the direct hydrothermal
synthesis technique. The as-synthesized membranes were evaluated for H2/CO2 separation in the
context of pre-combustion CO2 capture. Scanning electron microscopy (SEM) was used to check
the surface morphology while x-ray diffraction (XRD) was used to check the crystallinity of the
sodalite crystals and as-synthesized membranes. Single gas permeation of H2, CO2, N2 and mixture
gas H2/CO2 was used to probe the quality of the membranes. Gas permeation results revealed
nanocomposite membrane prepared via the PPH synthesis protocols using two interruption steps
displayed the best performance. This was attributed to the enhanced pore-plugging effect of sodalite
crystals in the pores of the support after the second interruption step. The nanocomposite membrane
displayed H2 permeance of 7.97 107 mols1m2Pa1 at 100 C and 0.48 MPa feed pressure
with an ideal selectivity of 8.76. Regarding H2/CO2 mixture, the H2 permeance reduced from
8.03 107 mols1m2Pa1 to 1.06 107 mols1m2Pa1 at 25 C and feed pressure of 0.18 MPa.
In the presence of CO2, selectivity of the nanocomposite membrane reduced to 4.24.
