Hydrogen production during processing of radioactive sludge containing noble metals

摘要

Hydrogen was produced when radioactive sludge from Savannah River Site radioactive waste containing noble metals was reacted with formic acid. This will occur in a process tank in the Defense Waste Facility at SRS when waste is vitrified. Radioactive sludges from four tanks were tested in a lab-scale apparatus. Maximum hydrogen generation rates varied from 5 (times)10(sup (minus)7) g H(sub 2)/hr/g of sludge from the least reactive sludge (from Waste Tank 51) to 2 (times)10(sup (minus)4) g H(sub 2)/hr/g of sludge from the most reactive sludge (from Waste Tank 11). The time required for the hydrogen generation to reach a maximum varied from 4.1 to 25 hours. In addition to hydrogen, carbon dioxide and nitrous oxide were produced and the pH of the reaction slurry increased. In all cases, the carbon dioxide and nitrous oxide were generated before the hydrogen. The results are in agreement with large-scale studies using simulated sludges.