Hydrogen separation in doped and blend polymer membranes

Polymer blend membranes of polysulphone (PSF) and polycarbonate (PC) in different concentration ratios (9:1, 3:1 and 1:1) were prepared by a solution cast method. FeCl 3 doped polycarbonate membranes in different concentrations ratios (10, 20 and 30) were also prepared using the same technique. The gas permeability of H 2 and CO 2 has been observed for these samples. The doped membranes were etched in 6 N NaOH at 60 ( ± 2 ) ∘ C by step etching and the permeability was observed for every step. It was observed that the permeability of the membranes was increased with an increase in etching time. The rapid variation in permeability was found after a critical etching time. The formation of C–Fe bonds in the polymer may be improving its stability against the etchant. In the blend membrane, it was observed that as the concentration of PC in PSF increases the permeability of both the gases ( H 2 and CO 2 ) increases. The permselectivity of hydrogen over carbon dioxide was calculated to be 2.52 for pure PSF and it reduces as the concentration of PC in PSF increases. The optical micrograph shows complete dispersion of FeCl 3 in PC and XRF confirms the elemental composition.