Green Synthesis of Copper Nanoparticles Using Alchornea laxiflora Leaf Extract and Their Catalytic Application for Oxidative Desulphurization of Model Oil

Abstract

Copper nanoparticles were biosynthesized using aqueous plant leaf extract of Alchornea laxiflora as reducing and capping agents. The as synthesized copper nanoparticles (CuNPs) were confirmed by the colour change after addition of the aqueous leaf extract of Alchornea laxiflora into copper sulphate solution. The CuNPs were characterized by UV–Visible spectrophotometer, high-resolution transmission electron microscopy (HRTEM), energy-dispersive x-ray spectroscopy (EDX), and Fourier transform infrared (FTIR) spectrophotometer. The result of HRTEM reveals the formation of CuNPs with an average size of 3.29 ± 0.57 nm. The biosynthesized CuNPs gave absorption at 364 nm and the FTIR spectrum shows the Cu–O stretching vibration at 590 cm−1. The synthesized CuNPs show higher catalytic activity than the conventional acetic acid catalyst used in the oxidative desulphurization of model oil. The CuNPs can, therefore, serve as an inexpensive alternative catalytic material that can be used in the oxidative desulphurization (ODS) process.