The low hydrate formation rate, the low gas selectivity and the low gas storage capacity have been proved as the major bottlenecks for a successful application of CO₂ capture process using gas hydrates. Aluminum nanoparticles has an important specific area, which can lead to high heat and mass transfer efficiency, large gas dissolution, fast nucleation, and formation rate. In this work, CO₂-CH₄ hydrate formation with and without aluminum nanoparticles was investigated. Herein, the promoting mechanism and effects of aluminum nanoparticles concentrations for an initial pressure of 4.0 MPa and temperature of 274.15 K on CO₂-CH₄ hydrate formation process were studied experimentally. The obtained results showed that the nanoparticles of Al, beyond a certain minimum concentration, slightly enhanced the gas dissolution, notably improved the gas consumption by crystallization and dramatically improved the gas capture selectivity. These positive effects were observed at the beginning of the process and after that became negative.