Immobilized biogenic copper nanoparticles from metallic wastewater as a catalyst for triazole synthesis by a click reaction using water as a solvent

Abstract

In this study, biogenic copper nanoparticles from metallic wastewater were examined for the synthesis of triazoles by a click reaction. The size of the copper nanoparticles obtained by biogenic sulfate reduction of synthetic wastewater using sulphate-reducing bacteria was in the range of 5–10 nm. Copper nanoparticles immobilized in polyvinyl alcohol and sodium alginate (PVA-SA-CuNPs) were prepared and then characterized by field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX), field emission transmission electron microscopy (FETEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and UV-vis spectroscopy. The catalytic activity of PVA-SA-CuNPs was assessed in the three-component click synthesis of 1,2,3-triazoles in water under low catalyst loading and mild reaction conditions. The nanocatalysts can be recycled and reused up to 5 times without significant loss of their catalytic activity.