CO2 Capture and Direct Air CO2 Capture Followed by Integrated Conversion to Methane Assisted by Metal Hydroxides and a Ru/Al2O3 Catalyst

Abstract

AbstractRising CO2 levels are leading to an increase in atmospheric greenhouse gas effect. Hydroxide salts have previously been shown to be promising reagents for capturing CO2. Utilizing a 5 %Ru/Al2O3 catalyst, the carbonates obtained through CO2 capture can then be hydrogenated to methane. This conversion occurs at relatively mild temperatures from 200 °C to 250 °C under 40 to 70 bar H2 with yields of up to 100 %. Natural sources of calcium carbonate, like eggshells and seashells, can also be partially converted to methane. The direct air CO2 capture and conversion of CO2 to methane was achieved as well in quantitative yields.