Hyperbranched polymer composite membrane using water as solvent for separating aromatic/aliphatic hydrocarbon mixtures

The separation of aromatic/aliphatic mixtures is significant in chemical industry. Pervaporation has attracted increasing attention due to its low energy consumption and environmentally friendly process. However, the formation of membranes mostly use toxic organic solvents, whereas in this study water was used instead to prepare membrane in separating aromatic/aliphatic mixtures. W3000 were dispersed in water to form micelles, which were then deposited onto the surface of the tubular porous ceramic substrate through the negative pressure-driven assembly method. The emulsion and composite membranes were characterized by TEM, SEM and FTIR. The crosslinking density of W3000 was also tested using NMR XLD analyzing system. The membranes were used for separating aromatic/aliphatic mixtures through pervaporation. The results showed that compared with the membrane prepared by DMF, the pervaporation separation index (PSI) of the composite membrane formed using water as solvent was 3.3-fold increased for separating toluene/n-heptane mixtures. The as-prepared composite membranes showed a better comprehensive pervaporation performance. This facile strategy may have a potential in the application of pervaporation for separating aromatic/aliphatic mixtures in industry. (C) 2017 Elsevier B.V. All rights reserved.