Preparation and characterisation of Tl2Pu(MoO4)3 and Tl4Pu(MoO4)4 in Tl–Pu–Mo–O system by X-ray and thermal methods

• Published in: Journal of nuclear materials 2008-05, Vol.376 (2), p.129-132
• Main Authors: Dahale, N.D., Keskar, Meera, Sali, S.K., Venugopal, V.
• Format: Article
• Language: English
• Subjects: Applied sciences; Controled nuclear fusion plants; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fission nuclear power plants; Fuels; Installations for energy generation and conversion: thermal and electrical energy; Nuclear fuels
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/j.jnucmat.2008.01.028

The quaternary Tl–Pu–Mo–O system was investigated for the first time and two new quaternary compounds Tl2Pu(MoO4)3 and Tl4Pu(MoO4)4 were synthesized by solid state reactions of Tl2MoO4 with Pu(MoO4)2 in 1:1 and 2:1 molar proportions at 773K and 823K, respectively. X-ray powder diffraction data of these compounds were indexed on orthorhombic system. Thermogravimetric (TG) curves of Tl2Pu(MoO4)3 and Tl4Pu(MoO4)4 were recorded in air and no significant weight changes were observed up to 973K and 1033K, respectively. Differential thermal analysis (DTA) curves of Tl2Pu(MoO4)3 and Tl4Pu(MoO4)4 showed endothermic peaks due to the melting of the compounds at 838K and 1013K, respectively. Non-isothermal kinetics of decomposition of Tl2Pu(MoO4)3 and Tl4Pu(MoO4)4 in air was studied using thermogravimetric technique. Tl2Pu(MoO4)3 and Tl4Pu(MoO4)4 when heated up to 1673K decomposed to Tl2O and MoO3 in the gaseous form, giving solid PuO2 as an end product. The reactions followed unimolecular nucleation and growth mechanism with activation energies of 106kJ/mol and 157kJ/mol, respectively.