Thermal decomposition and dehydration kinetics of tetra(piperidinium) octamolybdate tetrahydrate in air

Thermal decomposition of tetra(piperidinium) octamolybdate tetrahydrate, [C5H10NH2](4)[Mo8O26]center dot 4H(2)O, was investigated in air by means of TG-DTG/DTA, DSC, TG-IR and SEM. TG-DTG/DTA curves showed that the decomposition proceeded through three well-defined steps with DTA peaks closely corresponding to mass loss obtained. Kinetics analysis of its dehydration step was performed under non-isothermal conditions. The dehydration activation energy was calculated through Friedman and Flynn-Wall-Ozawa (FWO) methods, and the best-fit dehydration kinetic model function was estimated through the multiple linear regression method. The activation energy for the dehydration step of [C5H10NH2](4)[Mo8O26]center dot 4H(2)O was 139.7 kJ/mol. The solid particles became smaller accompanied by the thermal decomposition of the title compound.