Influence of Nickel Foam on Kinetics and Separation Efficiency of Hydrate-based Carbon Dioxide Separation

Abstract Hydrate-based Carbon dioxide (CO2) separation was widely concerned because of its simple process and low energy consumption. Mechanical stirring could promote gas-liquid-hydrate three-phase contact and hydrate formation but consumed lots of energy. Therefore, it was necessary to develop more efficient technologies. Nickel foam (Ni–F) is an excellent hydrogen (H2) storage material with properties of porous structure and good thermal conductivity which are helpful to heat and mass transfer. In this work, by comparing the rate of gas consumption and CO2 separation efficiency, the influence of Ni–F on the hydrate-based CO2 separation was systematically studied. The results showed, firstly, both the gas consumption rate and CO2 separation efficiency were increased by using Ni–F instead of mechanical agitation; secondly, it was firstly found the clear peaks corresponding to H2 in the Raman spectra of the hydrates formed in the presence of Ni–F under the presure >4.00 MPa and 273.85 K, which indicated that the Ni–F is helpful to the stability of H2 in hydrate. The results were not only significant for the further development of hydate-based CO2 separation process, but also provided a possible research direction for hydate-based H2 storage.