Gas separation properties of crosslinked and non-crosslinked carboxymethylcellulose (CMC)membranes

In this study, crosslinked and non-crosslinked carboxymethylcellulose (CMC) membranes were prepared with dierent concentrations of polymer. Then, the permeability of pure CO2, N2, and CH4 was measured through these membranes in dry state to investigate the in uence of polymer concentration and applied feed pressure on permeability and permselectivity. The permeability of CO2 through membranes was higher than the other gases. A comparison of permeabilities revealed that the permeability of N2, CO2, and CH4 increased on an average of 33, 40 and 20 percent, respectivly, by increasing the feed pressure from 6 to 10 bar. Increasing CMC concentration from 1.2 to 3.0 wt%, the permeability of N2, CO2, and CH4 decreased on an average of 25, 12 and 19 percent, respectivly. Also, the CO2/CH4 and CO2/N2 permselectivities increased 9 and 18 percent, respectivly, with an increment in CMC concentration from 1.2 to 3 wt%. The crosslinked CMC membranes with the same polymer concentrations were also prepared to investigate the eects of crosslinking reaction on permeability and permselectivity. The ATR-FTIR test was applied, and the peak at about 1108 cm??1 conrmed the presence of corsslinker groups. The comparision of gas permeation test results for crosslinked and non-crosslinked CMC membranes showed that the gas permeability decreased and its permselectivity increased due to crosslinking reaction. According to Robesonʹs plots, the prepared CMC membranes would have potential for commercialization.