Thermal decomposition behaviour of lanthanum(III) tris-tartrato lanthanate(III) decahydrate

Lanthanum(III) tris-tartrato lanthanate(III) decahydrate, La[ La(C4H4O6)(3)]. 10H(2)O has been synthesized and characterized by elemental analysis, IR, electronic spectral and X-ray powder diffraction studies. Thermal studies (TG, DTG and DTA) in air showed a complex decomposition pattern with the generation of an anhydrous species at similar to170degreesC. The end product was found to be mainly a mixture of La2O3 and carbides at similar to970degreesC through the formation of several intermediates at different temperature. The residual product in DSC study in nitrogen at 670 degreesC is assumed to be a similar mixture generated at 500 degreesC in TG in air. Kinetic parameters, such as, E*,DeltaH,DeltaS, etc. obtained from DSC are discussed. IR and X-ray powder diffraction studies identified some of the decomposition products. The tentative mechanism for the thermal decomposition in air of the compound is proposed.