Catalyst for Selective Oxidation of Ammonia to Nitrogen and Water

The cost of delivering payloads to remote destinations in space is extremely high, and even the smallest weight reductions can result in substantial cost savings. Consequently, systems that have been designed for low Earth orbit may not be suitable for a mission to Mars. One example of this is the system to recycle waste water. A system that utilizes vacuum distillation and catalytic oxidation (VPCAR) is being developed for Mars missions. A key step in the VPCAR process is the gas phase oxidation of ammonia to nitrogen and water without forming NOX. In Phase I TDA Research Inc. developed catalysts for this reaction. Our approach to the problem was centered on the development of a bifunctional catalyst, which could separate adsorbed oxygen and nitrogen atoms, thereby reducing NOX formation. In Phase I we identified a catalyst formulation, which converted 100% of the ammonia feed at temperatures where very low concentrations of NOX were produced. In Phase II, we will refine the catalyst composition, test both ammonia and hydrocarbon oxidation reactions in a pilot scale reactor, and then, in work carried out at Hamilton Sundstrand, we will test the reactor on a full-scale unit.