hrvatski

Thermal decomposition of calcium(II) bis(acetylacetonate) n-hydrate

The objective of this study was to investigate the thermal decomposition path of calcium bis(acetylacetonate) n-hydrate (Ca(C5H7O2)2×nH2O). Thermal analysis of the investigated complex was accomplished using Simultaneous Differential Thermal and Thermo- Gravimetric Analysis (DTA/TGA) performed in dynamic air atmosphere up to 1, 300°C. The obtained curves have been interpreted on the basis of 1H and 13C Nuclear Magnetic Resonance (NMR), Fourier-transformed Infra-Red (FTIR) Spectroscopy and X-Ray Diffraction (XRD) analysis of samples whose thermal treatment was interrupted at various temperatures. A total of six thermal decomposition steps, resulting in a total mass loss of 80%, has been observed: the release of adsorbed and coordinated water molecules in temperature intervals of 46-105°C and 105- 175°C, respectively ; two-step chelate decomposition processes in temperature interval of 175-305°C and 305-635°C, accompanied by the formation of calcite ; and calcite decarboxylation and formation of calcium oxide in temperature interval between 635-800°C and oxidation of amorphous carbon residues at temperatures above 800°C.

FT-IR spektroskopija; kalcijev bis(acetilacetonat); rendgenska difrakcija; toplinski raspad

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