J. C. Sullivan

Radiation Chemistry of Synthetic Waste

The yield of hydrogen from radiolysis of aqueous solutions is substantially reduced by the presence of nitrate and nitrite in the waste solutions. Nitrate is more efficient in scavenging the precursors to hydrogen than is nitrite, therefore, the latter should be maintained at higher levels if minimization of radiolytic gas production is required. Nitrate is the major scavenger for e(sub aq)(sup (minus)) and nitrite is the major scavenger for H atoms. At the concentration levels of the waste solutions some fraction of the radiation energy will be absorbed directly by the solutes, primarily the nitrate/nitrite components. Organic additive will increase the generation of hydrogen and mechanistic information is available to allow predictive modeling of trends in the rate of the generation. Physical parameters such as temperature, viscosity, and pressure will not significantly affect the gas generation relative to its generation under normal conditions. Radiolytic generation of N2O is very inefficient in the absence of organic solutes. No mechanistic information is available on its generation in the presence of organic additives. At the concentration levels of the inorganic salts in the waste solutions, it will be very difficult to find a chemical additive that could efficiently reduce the yield of the generated hydrogen, except, perhaps, increasing the concentration of the nitrite/nitrate components.

Radiolytic Generation of Gases from Synthetic Waste, Annual Report: 1991

Annual report of an Argonne National Laboratory Chemistry Division program on radiolytic generation of gases from synthetic waste. This report includes results of studies on simulated waste solutions to measure the presence and absence of organic chelators and their products.