A second life for CO2

processing the CO2 filtered from the air. "We let the CO2 react with hydrogen to form methane, or CH4. This is synthetic natural gas," he explains. "This reaction releases a lot of heat, which we can use [...] we have extracted from the air during CO2 capture ," he explains. In the process, one molecule of CH4 becomes one C (carbon) and two H2 (hydrogen). The hydrogen can be used as an environmentally friendly [...] decompose the methane in the absence of oxygen." Temperatures above 1,000°C are required for the CH4 molecule to split into its constituent carbon and hydrogen. One problem here is that while the hydrogen …