In this research, dissolution of methane in water with CuO nanoparticles was examined at temperatures of 20, 15, 10, 8, 6 and 3 °C and at pressures of 10 and 15 bar. For this purpose, four samples including pure water, water with surfactant and two nanofluids with different concentrations were prepared. Each sample volume was 200 cm3. Methane was contacted with each solution in a reactor with no mixer. Addition of 0.05 wt.% SDS reduced surface and interfacial tensions by accumulating at the interface of immiscible fluids. This implies higher solubility of methane comparing with the pure water. The same procedure happened for 0.1 wt.% CuO nanoparticles, as well. It was concluded that high effective surface area of nanoparticles improved the solubility. Furthermore, adding 1 wt.% nanoparticle, increased methane solubility by 144% and 77.15% at pressures of 10 and 15 bar (compared with the pure water), respectively.
