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  • 1 Northeastern University College of Materials & Metallurgy 110005 Shenyang People’s Republic of China
  • | 2 Liaoning Shihua University 113001 Fushun People’s Republic of China
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Abstract  

Ammonium niobium oxalate was prepared and characterized by elemental analysis, XRD and FTIR spectroscopy analysis, which confirmed that the molecular formula of the complex is NH4(NbO(C2O4)2(H2O)2)(H2O)3. Dynamic TG analysis under air was used to investigate the thermal decomposition process of synthetic ammonium niobium oxalate. It shows that the thermal decomposition occurs in three stages and the corresponding apparent activation energies were calculated with the Ozawa–Flynn–Wall and the Friedman methods. The most probable kinetic models of the first two steps decomposition of the complex have been estimated by Coats–Redfern integral and the Achar–Bridly–Sharp differential methods.