Thermal decompositions of scandium(III) m-nitrobenzoate, m-chlorobenzoate, m-hydroxybenzoate and m-aminobenzoate in air atmosphere

Abstract

The conditions of thermal decomposition of scandium(lll) m-nitrobenzoate, mchlorobenzoate, m-hydroxybenzoate and m-aminobenzoate were studied. On heating, most of these carboxylates decompose in two steps; only scandium(Ill) 3-aminobenzoate decomposes in one step. The hydrated complexes first lose crystallization water and are then transformed to Sc20 3. The hydration of the complexes is accompanied by an endothermic effect, and the decomposition of the anhydrous complexes by a strong exothermic effect. Scandium(Ill) 3-nitrobenzoate decomposes explosively.Rare earth element complexes with m-benzoic acids are little known, mHydroxybenzoates of Y, La and lanthanides have been prepared as hydrated salts with a metal to ligand ratio of 1 : 3 [1-4], their IR and X-ray spectra have been recorded and their thermal decompositions in air and nitrogen atmospheres have been studied. Pirkes et al. [5] isolated La, Ce(III), Pr(III), Nd and Sm(III) mnitrobenzoates with general formula Ln(NO2C6H4COO)3 9 2H20. During heating to 300 ~ these complexes are decomposed, m-Chlorobenzoates and maminobenzoates of rare earth elements have not been prepared.Scandium(III) complexes with m-benzoic acids have not been studied so far. The aim of our work was to obtain the m-nitrobenzoate, m-chlorobenzoate, mhydroxybenzoate and m-aminobenzoate of scandium(III) and to examine their thermal decompositions in air atmosphere.

Thermal decomposition of rare earth element suberates in air atmosphere

“…The yttrium suberate was prepared as hexahydrate, its IR and X spectra were recorded and thermal decomposition was studied [3]. Thermal decomposition of other rare earth element suberates have not been studied.As a continuation of our work on the thermal decomposition of rare earth carboxylates [4][5][6], we now report the thermal decomposition of the La and lanthanide suberates in air atmosphere. …”

Thermal decomposition of Co(II), Ni(II), Cu(II) and Zn(II) hippurates

“…As a continuation of our work on the thermal decomposition of aminoearboxylates of transition [4,5,6] and intratransition elements [5], we now report on the thermal decomposition of Co(II), Ni(II), Cu(II) and Zn(II) hippurates during heating in air atmosphere. …”