Synthesis of Highly Hydrophilic Cellulose and Graphene Oxide Based Membranes: Application in Alcohol Dehydration

Combining highly ionic and very insoluble materials can be used to separate solvents with high water miscibility. In this work cellulose and Graphene Oxide (GO) were cross-linked by highly ionic N, N′-bis-(2-aminoethyl)-4,4′-dipyridinium bromide (BAEB) molecules to the preparation of CELL-BAEB and GO-BAEB membranes for alcohol dehydration. Fourier Transform InfraRed (FT-IR), proton nuclear magnetic resonance (1HNMR), X-Ray Photoelectron Spectroscopy (XPS), Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive X-ray Spectroscopy (EDS), and Thermogravimetric Analysis (TGA) analyses were used to characterize the synthesized compounds. For ethanol, isopropyl alcohol (IPA), and n-butanol in a feed water concentration of 5-40 wt% and at a temperature range of 40-70°C, sorption parameters, including water content in the membrane, alcohol content in the membrane, swelling, and selectivity also pervaporation parameters, including water content in permeate, total flux, and separation factor, have been evaluated. The water content in the membrane was as high as 269 wt%, 276 wt%, 287 wt% for CELL-BAEB, and 188 wt%, 193 wt%, and 211 wt% for GO-BAEB in 40 wt% feed water at room temperature, and the separation factor was 3951, 4491, and 5616 for CELL-BAEB, and 2423, 3094, and 3741 for GO-BAEB in 10 wt% feed water at70 oC, for ethanol, IPA, and n-butanol, respectively. It was shown that the high flux and selective CELL-BAEB and GO-BAEB membranes are highly effective in separating water from alcohol.