Destruction of propellant components in supercritical water

Supercritical water oxidation is an innovative, relatively low-temperature process that can give high destruction efficiencies for a wide variety of hazardous chemical wastes. It takes place in a water medium with added oxidant above the critical point of water. In this paper we present preliminary results for the destruction of propellant components in supercritical water without added oxidant. Reactions of ammonium perchlorate and nitromethane are examined using a flow reactor made of Hastelloy C276 operated at temperatures as high as 580{degree}C at pressures near 38.7 MPa. (5500 psig). Over 99.8% of the ammonium perchlorate is destroyed in less than 15 seconds at 500{degree}C. The reaction produces primarily chloride ion, nitrous oxide, and oxygen. A small amount of the nitrogen is converted into nitrate ion and nitrite ion. No reaction is detected in 180 seconds at temperatures below 400{degree}C. For nitromethane, over 99% is destroyed at 500{degree}C within 30 seconds. The reaction produces negligible amounts of nitrate and nitrite. Effluents from both ammonium perchlorate and nitromethane experiments were analyzed for metal ions that could results from corrosion of the reactor.