Advanced toluene/n-heptane separation by pervaporation: investigating the potential of graphene oxide (GO)/PVA mixed matrix membrane

• Published in: Journal of the Taiwan Institute of Chemical Engineers Vol. 150; p. 105025
• Main Authors: Pakizeh, Majid, Karami, Mahdi, Kooshki, Sahar, Rahimnia, Rasoul
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-09-2023
• Subjects: Aliphatic/Aromatic separation; Graphene oxide (GO); MMM; Pervaporation; Polyvinyl alcohol (PVA); Polyvinyl alcohol (PVA); Aliphatic/Aromatic separation; Graphene oxide (GO); MMM; Pervaporation
• ISSN: 1876-1070; 1876-1089
• DOI: 10.1016/j.jtice.2023.105025

•The effects of different molecular weights of PVA polymer on the membrane performance were investigated using a PV process.•PVA with a molecular weight of 130,000 showed the optimum toluene separation properties.•GO/PVA mixed matrix membranes with different loadings of GO were prepared, characterized and used for aromatic mixture separation.•Effective toluene separation from n-heptane was achieved at 1.5 wt.% of GO loading.
The separation and purification of aromatic/aliphatic hydrocarbon mixtures from petroleum feedstocks is a significant industrial undertaking that poses several challenges. This task is commonly encountered during the production of ultralow-sulfur gasoline and naphtha reforming processes, both of which are critical for various industries. Recently, membrane pervaporation for separating aromatic/aliphatic mixtures is regarded as a promising option compared to conventional methods due to its energy efficiency.
The preparation of a cross-linked polyvinyl alcohol (PVA) membrane with varying molecular weights, is aimed at effectively separating toluene/n-heptane. To further enhance the separation efficiency, mixed matrix membranes (MMMs) were fabricated by incorporating graphene oxide (GO) at different loadings.
The PVA membrane with a molecular weight of 130,000 was utilized as the polymer phase, as it exhibited a permeation flux of 24.8 g/m2h and a separation factor of 5.5. Increasing the GO loading from 0.5 to 1.5 wt% increased total flux; however, further increments in GO content led to a decrease in flux. Notably, the PVA-1.5GO sample demonstrated optimum performance, with a total permeation flux of 30.6 g/m2h, separation factor of 11.9. For this sample, pervaporation separation index (PSI) of 333.54 was obtained, indicating a 199% increase compared to that of pure PVA membrane (111.4).
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