A THERMOANALYTICAL STUDY OF METAL ACETYLACETONATES

The thermal decomposition reactions of iron(III) and zinc(II) acetylacetonates, in dry nitrogen were thoroughly studied. Thermal events occurring throughout the decomposition range (room temperature to 1000-degrees-C) were monitored by means of thermogravimetry and differential thermal analysis. These events were characterized on the basis of solid and gas product analyses, using X-ray diffractometry and infrared spectroscopy- Non-isothermal kinetic parameters (A, kappa and DELTA-E) were determined. The results showed Zn(C5H7O2)2.2H2O dehydrates at less-than-or-equal-to 110-degrees-C, and, then, decomposes similarly to Fe(C5H7O2)3 via a complex pathway. The ultimate products at greater-than-or-equal-to 600-degrees-C were ZnO and Fe2O3. The metal acetates and mixed metal carbonate-oxide phases were observed as intermediate solid products. Gas phase products included propyne, acetone, isobutene, methane and carbon oxides. Some of these were initial decomposition products, whereas others resulted from interfacial reaction involving the initial products.