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


1 Department of Energy Engineering, Sharif University of Technology, Tehran, Iran

2 Department of Chemical & Petroleum Engineering, Sharif University of Technology, Tehran, Iran


In this study, crosslinked and non-crosslinked carboxymethylcellulose (CMC) membranes were prepared with different concentrations of polymer. Then, the permeability of pure CO2, N2, and CH4was measured through these membranes in dry state,to investigate the influence of polymer concentration and applied feed pressure on permeability and permselectivity. The permeability of CO2through 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/CH4and 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 investigating(to investigate) theeffects of crosslinking reaction on permeability and permselectivity.The ATR-FTIR test was applied,and the peak at about 1108 cm-1 confirmed 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 Robeson’s plots, the prepared CMC membranes would have potential for commercialization.