High Temperature Reactor: Driving Force to Convert CO₂ to Fuel

The rapidly increasing cost of petroleum products and uncertainty of long-term supply have prompted the U.S. military to aggressively pursue production of alternative fuels (synfuels) such as coal-to-liquids (CTL). U.S. Air Force is particularly active in this effort while the entire military is involved in simultaneously developing fuel specifications for alternative fuels that enable a single fuel for the entire battle space; all ground vehicles, aircraft and fuel cells. By limiting its focus on coal, tar sands and oil shale resources, the military risks violating federal law which requires the use of synfuels that have lifecycle greenhouse gas emissions less than or equal to emissions from conventional petroleum fuels. A climate-friendly option would use a high temperature nuclear reactor to split water. The hydrogen (H₂) would be used in the reverse water gas shift (RWGS) to react with carbon dioxide (CO₂) to produce carbon monoxide (CO) and water. The oxygen (O₂) would be fed into a supercritical (SC) coal furnace. The flue gas CO₂ emissions would be stripped of impurities before reacting with H₂ in a RWGS process. Resultant carbon monoxide (CO) is fed, with additional H₂, (extra H₂ needed to adjust the stoichiometry: 2 moles H₂ to one mole CO) into a conventional Fischer-Tropsch synthesis (FTS) to produce a heavy wax which is cracked and isomerized and refined to Jet Propulsion 8 (JP-8) and Jet Propulsion 5 (JP-5) fuels. The entire process offers valuable carbon-offsets and multiple products that contribute to lower synfuel costs and to comply with the federal limitation imposed on synfuel purchases. While the entire process is not commercially available, component parts are being researched; their physical and chemical properties understood and some are state-of-the-art technologies. An international consortium should complete physical, chemical and economic flow sheets to determine the feasibility of this concept that, if pursued, has broad applications to military and civilian aviation fleets and freight-hauling diesel engines.