Closure of the oxygen loop will be a critical requirement during future, long-duration, manned missions. The current carbon dioxide reduction assembly recaptures oxygen as water via the Sabatier reaction, in which, four moles of H2 and one mole of CO2 react to form one mole of CH4 and two moles of H2O losing half of the input H2. In contrast, the Bosch reaction produces H2O and elemental carbon with the recovery of all H2, while closing the oxygen loop. Historically, Bosch reactors have been embodied as batch type reactors where the catalyst is initially loaded and the reactor is operated until the carbon product blocks the gas flow producing an unacceptable back pressure. A Bosch reactor designed for continuous operation requires the addition of make up catalyst and separation of the carbon from the recirculating gases with no down time. The proposed catalyst introduction system and carbon separation and storage system will utilize a semi-continuous feed of catalyst and mechanically assisted removal of the carbon product and spent catalyst from the reactor to allow for continuous operation. This Phase II effort will focus on the development, testing, and delivery to NASA of a continuous flow reactor system that removes and stores the product carbon. These efforts will aid NASA in meeting the NASA Technology Roadmaps - TA6: Human Health, Life Support and Habitation Systems air revitalization goal of 100% oxygen recovery.
The proposed Bosch Reactor technology has a strong potential for use by government and the private sectors. The government application will be as Flight Hardware for deployment in support of future long duration exploration objectives beyond Low Earth Orbit (LEO) where closed loop air revitalization will play a critical role in reducing Environmental Control and Life Support System (ECLSS) logistics. In addition, such a system can be used to recover oxygen from the carbon dioxide present in the Martian atmosphere.
Ground based applications include mitigation of industrial carbon dioxide emissions into the atmosphere that add to the burden of greenhouse gases. The Bosch technology is also capable of decomposing methane into carbon and hydrogen. Additionally radioactive hydrogen-carbon compounds can be decomposed to easily storable carbon.