High temperature heat capacity of PuPO4 monazite-analogue

The enthalpy increments of PuPO4 have been measured using drop calorimetry in the temperature range from 530 K to 1386 K. The heat capacity was derived from the obtained data and compared with heat capacity data obtained directly from differential scanning calorimeter measured in this study from 400 K to 1400 K. The recommended heat capacity of PuPO4 was determined based on both techniques as:Cp0(JK-1mol-1)=126.600+32.999×10-3(T/K)-1.9503×106(T/K)-2.

► The heat capacity of PuPO4 has been measured up to 1400 K.
► Good agreement between the DSC and the drop technique has been found.
► It was demonstrated that drop calorimetry is precise enough to measure relatively small samples.