Carbon monoxide equilibrium pressures and phase relations during the carbothermic reduction of uranium dioxide

Critical review of carbon monoxide pressure measurements in the uranium–carbon–oxygen ternary system

“…This carbothermic reduction reaction study [19] is similar to earlier CO pressures measurements of Piazza and Sinnot [2] since the experimental vessel and the manometric devices are based on this previous work. So, the thermomolecular effect is corrected accordingly.…”

“…First of all, it was necessary to reduce U 3 O 8 into UO 2 by a temperature step performed in the 973-1273 K temperature range under vacuum. The reaction was carried out in a graphite crucible contained in a heated vacuum furnace which was closed during the measurements, this apparatus being identical to the device used by Hennecke [19]. The corrections are thus calculated taking into account the same vessel geometry.…”

“…The critical analysis of literature data is performed on mass-spectrometric measurements [18] and on manometric pressure determinations either by applying the thermomolecular effect correction for data measured in the molecular flow regime or using our formula (8) for those performed in the transition flow regime [2,3,5,[19][20][21]. For all the studies considered (see Tables 2 and 3 As a general rule, the gas phase composition was either analysed directly by mass spectrometry [18] or following the mass spectrometric analysis of gas.…”

An off-line method to characterize the fission product release from uranium carbide-target prototypes developed for SPIRAL2 project

“…High temperatures and high irradiation doses will modify considerably the initial properties of the material and could lead to the collapse of the material by swelling, polygonization or amorphization [15][16][17][18][19][20][21][22][23][24]. Alternative ways to produce these UC x targets were examined such as the carbothermal reduction at high temperature of other uranium precursors such as oxide [25,26] or oxalate [24]. Stoichiometric proportions of uranium and graphite can be also arc-melted to produce pure UC pellets [27].…”