EXPERIMENTS ON THE PREPARATION OF UO$sub 2$-X AND UO

Abstract

Reactions designed to reduce the oxygen content of UO2 below stoichiometric composition are described. No evidence was found for the existence of substoichiometric U02-The reaction of metal with UOj + ^ yields a phase described in the literature as uranium monoxide, UO. However, the reaction proceeds at a low rate and the reaction products are contaminated with a large amount of U02-The reaction of UC with UOj is described: this reaction is capable of producing a single-phase material of composition ^^x^Ux ^'-^'^^ ^y *«*'»•»« «•« vacuum at 1600 to 1800 C.

Oxidation and Gas Release Behavior of UC, U(C,N) and UN at High Temperature

“…The gas release progress curves considered from the above reactions would indicate that Eqs. ( 1) , (2) , (5) and (8) would be first order reactions conforming with Langmuir's adsorption isotherm, indicating rapid consumption of the oxygen source. The release rates plotted against time revealed steep initial slopes decreasing rapidly, somewhat ressembling the shape of the 1,2000C curve of Fig.…”

“…Accounting thus for the amounts of oxygen consumed in various reactions, the quantities of CO finally remaining for evolution was estimated from Eqs. ( 1) and (2).…”

“…The replacement of carbon by oxygen in the carbide structure to form monoxicarbides of U and U-Pu has been studied by investigators such as Vaughan et al (2), Magnier et alYl, Stoops et al (6) , Sano et al (5), Brett et a[. (4) and Taylor et al (1), Henry(8) has reviewed all the available data and concluded that these appeared to be a maximum replacement of about 0.35 oxygen atoms for 1 carbon atom.…”

An Investigation of Uranium Corrosion in 100 C Water and 200 C Steam at Atmospheric Pressure

“…At temperatures above 80 C in degassed or hydrogen-containing water uranium corrodes rapidly to form a volunainous loosely adherent oxide coating. It is believed^ ' that atomic hydrogen migrates through the initial oxide film formed in Equation (1) and reacts with the uranium to form hydride as shown in Equation (2). This hydride layer is between the metal and the oxide and spoils the adherence of the oxide to the metal so that it no longer is protective* '.…”