Matrimid®/LaNi5 mixed matrix membranes for selective hydrogen separation from industrial waste gas streams

Abstract

This study reports the synthesis, characterization, and evaluation of Matrimid®/LaNi5 mixed matrix membranes for selective hydrogen separation from industrial waste gas streams. Through a combination of experimental investigation and modelling, hydrogen absorption in LaNi5 intermetallic compounds and its impact on separation performance were explored. It was observed that the composite membranes exhibit significant enhancement in hydrogen permeation compared to pristine Matrimid® membranes. The results showed that Matrimid®/LaNi5 membranes deliver 5 times higher H2 permeability (107 Barrer) and higher selectivity (H2/CO2: 14.5, H2/N2: 83.5, H2/CH4: 78.5 and H2/CO: 84.5). Furthermore, hydrogen permeation flux modelling in Matrimid®/LaNi5 elucidated the contribution of each transport mechanism with high regression coefficients (>0.92) and within ±15 % error. Moreover, the results demonstrate the capability of Matrimid®/LaNi5 membranes to surpass Robeson upper bound for H2/CO2 while it is almost reached for H2/N2 and H2/CH4 separations, highlighting the potential of these new membranes for industrial-scale applications.