Temperature rising characteristics of ammonium diurante in microwave fields

The temperature rising characteristics of ammonium diurante, triuranium octaoxide (U3O8), and their mixture were investigated under microwave irradiation, aiming at exploring newly theoretical foundation for advanced metallurgical methods. The temperature rising curves showed that ammonium diurante had weak capability to absorb microwave energy, while triuranium octaoxide had the very strong absorption capability. The temperature of mixture containing 20% of U3O8 could rise from room temperature to 1171 K within 280 s. The ability to absorb microwave energy for the mixture with different ratios increased with the increase in the amount of U3O8. These are in good agreement with the results of Maxwell-Garnett effective medium theory. It is feasible to calcine ammonium diurante by adding of small amounts of U3O8 in microwave fields.