Design of Mn(II), Fe(III) and Ru(III) chalcone complexes: Structural elucidation, spectral, thermal and catalytic activity studies

Abstract

New Mn(II), Fe(III) and Ru(III) coordination compounds with chalcone ligand (L) were prepared. The synthesized complexes have been established by elemental analysis, molar conductance, XRD, TGA, magnetic moment measurements, and UV–vis, electron impact mass and IR spectral studies. The spectral and analytical data revealed that the ligand behaves as tridentate with an octahedral geometry for all complexes. Molecular orbital calculations used to confirm the geometry of the isolated compounds. The kinetic and thermodynamic parameters for decomposition steps have been calculated. Furthermore, the catalytic activity of the complexes toward the degradation of Methyl Orange was examined. The synthesized complexes were applied to treatment the analytical chemistry laboratories wastewater through the degradation of methyl orange indicator as heterogeneous catalysts in the existence of H2O2 as an oxidizer. The results of the study have shown all synthesized complexes have catalytic activity toward the degradation of Methyl Orange. The catalytic activity performance evaluation shows 24, 44 and 85% with Mn(II), Fe(III) and Ru(III) complexes as catalyst respectively. The effect of catalyst mass (0.5–1.2 mg) and concentration of H2O2 (137–826 ppm) were checked using Ru(III) complex which the highest catalytic activity. The degradation % was found in the range 29–78% after 100 minute using different concentrations of H2O2 (137.7–826.2 ppm) with Ru(III) as a catalyst. Also, the data elucidate the degradation of methyl orange increase with the amount of Ru(III) complex increase. The investigations show the reactions obey the first-order reaction mechanism, and the rate constants have been determined.