An investigation of the reaction of uranium with nitrogen - A thermogravimetric analysis study

In this work, the heating corrosion reaction of uranium with dry air and with dry nitrogen gas was investigated. Metallic uranium samples of different specific surface area and mass were reacted in a thermogravimetric analysis system at temperature ramping from 323 K to 1273 K at 15 K.min−1. Ignition was achieved during all heating profiles of the samples reacting with air, with the reported ignition temperature decreasing with increasing specific surface area. Heating cycles were conducted for the uranium and dry nitrogen gas system to investigate if ignition could be attained. These experiments were conducted by varying the specific surface area, sample mass, initial oxide thickness, nitrogen flow rate, and heating ramp rate. None of these experiments showed signs of clear ignition under dry nitrogen. It is hence suggested that uranium ignition under a dry nitrogen atmosphere is not readily attainable and would require a combination of extreme conditions, such as high heating ramp rate for a non-oxidised sample of high surface area and mass.