Hydrolysis of Uranium Carbides between 25 and 100°. II. Uranium Dicarbide, Uranium Metal-Monocarbide Mixtures, and Uranium Monocarbide-Dicarbide Mixtures

Reactions with water of as-cast uranium carbides with total-C: U atom ratios varying from 0.4 to 2.2 were investigated using gas chromatography for analysis of the gaseous products. Uranium metal-- uranium monocarbide mixtures yielded 2 moles of free hydrogen per mole of free metal, methane, small quantities of higher molecular weight gaseous hydrocarbons, and a hydrous uranium(IV) oxide. The gaseous products contained all the carbon originally present in the mixtures. Uranium dicarbide (UC/sub 1.85 plus or minus 0.03/) yielded a mixture of 36 hydrocarbons (average composition (vol%): methane, 15%; ethane, 28%; C/sub 3/ to C/sub 8/ alkanes, 7%; alkenes, 8%; alkynes, 0.6%; and unidentified unsaturates, 1%), free hydrogen (40 vol%), a water-insoluble wax, and a hydrous, uranium (IV) oxide. Forty per cent of the combined carbon was found in the gas and 25% in the wax. Varying the reaction temperature between 25 and 99 deg caused no change in the hydrolysis products from either uranium mono- or dicarbide. Hydrolysis of uranium monocarbide -- dicarbide mixtures resulted in a linear decrease in the volume% of methane and linear increases in the percentages of hydrogen and C/sub 2/ to C/sub 8/ hydrocarbons in the gas as the combinedC:U atom ratio increased from 1.0 to 1.85. Less methane was evolved from monocarbide-- dicarbide mixtures than expected from the monocaibide concentrations, indicating that some polymerization of C units had occurred. (auth)