OXIDATION OF 1,1-DIMETHYLHYDRAZINE (UDMH) IN AQUEOUS-SOLUTION WITH AIR AND HYDROGEN-PEROXIDE

The degradation of 1,1-dimethylhydrazine (UDMH), a component of some r ocket fuels, was investigated using atmospheric oxygen and hydrogen pe roxide. The reactions were carried out in the presence and absence of copper catalysis and at varying pH. Reactions were also carried out in the presence of hydrazine, a constituent, along with UDMH, of the roc ket fuel Aerozine-50. In the presence of copper, UDMH was degraded by air passed through the solution; the efficiency of degradation increas ed as the pH increased but the carcinogen N-nitrosodimethylamine (NDMA ) was formed at neutral and alkaline pH. Oxidation was not seen in the absence of copper. Production of NDMA occurred even at copper concent rations of < 1 ppm. Oxidation of UDMH with hydrogen peroxide also gave rise to NDMB. When copper was absent degradation of UDMH did not occu r at acid pH but when copper was present some degradation occurred at all pH levels investigated. The production of NDMA occurred mostly at neutral and alkaline pH. In general, higher concentrations of hydrogen peroxide and copper favored the production of NDMA. Dimethylamine, me thanol, formaldehyde dimethylhydrazone, formaldehyde hydrazone, and te tramethyltetrazene were also produced. The last three compounds were t ested and found to be mutagenic.