THERMOLYSIS AND THEIR KINETICS OF COPPER AND ZINC PERCHLORATE COMPLEXES WITH 2-AMINOPYRIDINE LIGAND

摘要

Copper and zinc perchlorate complexes with 2-aminopyridine (2-Apy) of the general formula [Cu(2-Apy)_3](ClO_4)_2.H_2O and [Zn(2-Apy)_2](ClP_4)_2 have been prepared and characterized by gravime-try, Fourier transform infrared (FT-IR), and C,H,N analysis. Thermal decomposition has been studied by thermogravimetry (TG) and differential thermal analysis (DTA). Kinetic parameters of their thermolysis were evaluated by model fitting as well as isoconversional methods using isothermal TG data. On applying model-fitting method average activation energy of thermal decomposition (α = 0.32, α is extent of conversion) was found to be 5.5 and 17.4 kJ mol~(-1), respectively, for copper and zinc complexes, whereas in the case of isoconversional method activation energy changes with extent of conversion (α). In order to evaluate the responses of rapid heating, explosion delay (D_E) measurements were undertaken. Activation energy of explosion were found to be 21.3 and 37.4 kJ mol~(-1) for copper and zinc complex, respectively. The explosion delay measurements and activation energy values have shown their thermal stability in the following order. [Cu(2-Apy)_3](ClO_4)_2.H_2O ＜ [Zn(2-Apy)_2](ClO_4)_2.