Permeability and Stability Analysis of Copper cation modified Graphene Oxide Membranes (CuX-GO) for Fuel Dehydration Applications

Graphene oxide (GO), which is a monolayer graphene sheet, forms highly selective nanochannels through GO sheet lamination. Metal cations, like copper (Cu2+), and polyatomic anions can crosslink with oxygenated functional groups on the GO sheet to form copper cation modified graphene oxide (CuX-GO). The Cu2+ to GO crosslinking can further accentuate GO membrane's permeation performance and stability, which is critical for potential fuel dehydration application of GO membranes. The objective of this project was to demonstrate the potential of applying CuX-GO membranes for fuel dehydration through fuel permeability, aqueous stability, morphology, and structural analysis. In this study, the permeability of hexane, heptane, and their mixture through the GO and CuX-GO membranes were recorded in the temperature range of 20 oC, 30 oC, 40 oC, and 50 oC to reliably determine the effectiveness of the membranes filtration applications. Stability tests were performed to measure the structural integrity of the membranes in a aqueous work environment. Morphology data of the membranes was also recorded to determine the correlation between surface roughness and modification from Cu2+. The results demonstrate that cation (Cu2+) impacts both permeability and stability of the GO membrane, while anions (X2-) only affect the stability.