Experimental study on effect of graphene surface chemistry on the process of methane hydrate formation and its storage and stability

Abstract In this research, the process of formation of methane hydrates was investigated in the presence of graphene and graphene oxide. First, the graphene nano sheets synthesized and growth on the copper substrate by the CVD method and It was structure was evaluated by XRD, FTIR and AFM analysis. Then, 1% wt. of stable graphene and graphene oxidized nanofluids were prepared and used in the process of gas hydrates formation at 1000 psig and at 4 C. As the nanofluid containing graphene / surfactant, while reducing the Induction and dissolution time to 46.0% and 60.9% respectively, compared to the pure water, could increase the storage rate to 56.7%. This is due to an increase of 40 times the initial dissolution of methane in the nanofluid than water, which is due to the reduction of the mass transfer resistance due to the presence of surfactant and the presence of heterogeneous active sites for nucleation. It was observed, however, the stability of hydrates in presence of graphene is less than graphene oxide, but after reaching the stability, the amount of methane deposited in graphene hydrate is greater than control sample of 34.9.