Investigation of industrial-scale carbon dioxide reduction using pulsed electron beams

Carbon dioxide is the most important greenhouse gas contributing to global warming. To help mitigate increasing CO2 concentrations, we investigate a method of carbon dioxide reduction using high-power electron beams, which can be used on an industrial scale. A series of experiments are conducted in which the reduction of CO2 is measured for different gas compositions and power deposition rates. An electron beam deposition model is applied to compute reduction rates of CO2 and energy cost for breaking a CO2 molecule in flue gas and pure carbon dioxide at atmospheric pressure. For flue gas consisting of 82% N2, 6% O2, and 12% CO2, the calculated energy cost is 85 eV per molecule. In order to dissociate 50% of the CO2 molecules, beam energy density deposition on the order of 20 J/cm3 is required. Electron beam irradiation of 12.6 liter gas volume containing 90% CO2 and 10% CH4 at beam energy density deposition of 4.2 J/cm3, accumulated over 43 shots in a 20 min interval, reduced the CO2 concentration to 78%....