Abstract: A process for removing CO2 from a methane-containing gas, having the steps of providing a methane-containing gas containing at least CO2 as an impurity, cooling the gas to remove CO2 from the methane-containing gas by freezing out same, and additionally reducing the CO2 concentration of the gas using a pressure temperature swing adsorption apparatus (PTSA), whereby a methane-enriched product gas is obtained. At least a part of the product gas is then used as treatment gas and is passed through the PTSA for treatment of the PTSA, whereby CO2 is absorbed by the treatment gas and is removed from the PTSA as a CO2-enriched treatment gas. The treatment gas is then recycled and admixed with the methane containing gas.