Synthesis, characterization, catalytic activity of Schiff base Cu-Complex and Ni-Complex for aromatic nitro compounds and methyl orange reduction

The environment and people are seriously threatened by organic dyes and aromatic nitro compounds (ANCs) that are discharged into water bodies by the dye and other industries without first being treated. It becomes important to eliminate or decrease these dangerous substances into less dangerous ones by employing straightforward techniques like reduction in the presence of metal complexes and NaBH 4 . Herein Schiff base metal complex of copper and nickel have been synthesized, and they have been characterized using a range of analytical methods, including fourier transform infrared (FT-IR), proton nuclear magnetic resonance (1H NMR), electrospray ionization mass spectrometry (ESI-MS), ultraviolet-visible (UV-Vis) spectroscopy, energy dispersive x-ray (EDX), elemental analysis, elemental mapping, and field emission scanning electron microscope (FE-SEM) imaging, X-ray photoelectron spectroscopy (XPS), etc. The reduction of 4-nitrophenol (4-NP), 4-nitroaniline (4-NA), and methyl orange (MO) was accomplished by the Schiff base metal complexes. With NaBH 4 , the catalysts effectively reduce the aromatic nitro compounds and methyl orange in an aqueous medium. 4-NP, 4-NA and MO were reduced by Cu-Complex in 9, 13 and 7 min with rate constant ( k ) value of 0.34, 0.042 and 0.50 min −1 respectively, while the Ni-Complex reduce 4-NP, 4-NA and MO in 3, 5 and 1 min with rate constant ( k ) value of 1.145, 0.40 and 2.07 min −1 respectively.