Effect of synthetic conditions on the morphology and gasoline desulfurization performance of microphase-separated membranes

Multicomponent polymer membranes containing poly(acrylonitrile-co-glycidyl methacrylate) (PANGMA) and ethyl cellulose (EC) were prepared under different synthetic conditions for gasoline desulfurization by pervaporation. Transmission electron microscopy was employed to study the morphologies of the PANGMA-EC membranes obtained under different synthetic conditions. The results showed that PANGMA-EC membranes had distinct microphase separation consisting of a dispersed EC phase and a continuous PANGMA phase. With increasing reaction temperature, the dispersed EC phase in the shape of isolated islands became smaller and more closely packed. Moreover, when decreasing the reaction concentration and the catalyst amount, the island phase composed of EC became smaller and mostly exhibited a long strip morphology. According to the analysis of the morphologies of the microphase-separated structures of the PANGMA-EC membranes obtained under different synthetic conditions, it was predicted that the permeation characteristics of gasoline components through the PANGMA-EC membranes increased with increasing reaction temperature and with decreasing reaction concentration and catalyst amount. This was verified by sorption and pervaporation experimental results of the PANGMA-EC membranes obtained under different synthetic conditions. Therefore, for the PANGMA-EC microphase-separated membrane, the modification of synthetic condition could contribute to higher permeation flux and sulfur enrichment factor compared with other reported membrane materials.