Biogas purification by CO2 removal using facilitated transport mechanism of cellulose nanocrystals/polyvinyl alcohol layered hollow fiber membranes

Abstract

AbstractBiogas can be a viable solution for replacing the conventional fuel for reducing pollution. However, the high CO2 content in biogas must be removed for its utilization. In this study, biogas purification is carried out employing cellulose nanocrystals (CNC)/polyvinyl alcohol (PVA) “selective layered” polysulfone hollow fiber membrane. The membrane chamber is designed such that the cross‐flow of the biogas can be ensured for the effective interaction of the biogas with membrane surface. From various characterization tools like field emission scanning electron microscope, FTIR, X‐ray diffraction, moisture absorption and tensile test, CNC1/PVA (1 wt% of CNC in PVA) nanocomposite film demonstrated optimum crystallinity and mechanical strength while retaining higher moisture absorption. The average selective layer thickness at this CNC concentration is 1169 nm. CO2 permeability of 17,858 barrer and the selectivity of 19 for CO2 over CH4 is observed, respectively.