Green synthesis of biodiesel from Citrus medica seed oil using green nanoparticles of copper oxide

Currently, increasing energy demand due to overpopulation has provoked an urge for renewable energy sources like biodiesel. Biodiesel production from non-edible seed oils provides striking solution to the problems associated with the energy crisis. In this study, the potential of Citrus medica as a novel and non-edible seed oil (33% w/w) producing feedstock was investigated for biodiesel production using green and recyclable nanoparticles (NPs) of copper oxide synthesized with aqueous leaf extract of Portulaca oleracea. Green NPs of copper oxide were characterized by advanced techniques like X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Diffraction X-Ray (EDX). A maximum yield of 93% of methyl ester was achieved at the optimum reaction condition of methanol to oil ratio 8:1, catalyst loading 0.18 wt%, reaction time 120 min and temperature 85 degrees C. Both Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance of biodiesel confirmed the presence of methyl ester in the synthesized biodiesel sample. Five distinct peaks of methyl esters were identified in biodiesel by gas chromatography-mass spectrometry (GC-MS) analysis. Fuel properties of methyl esters were investigated and found analogous to the international standards. The results indicated that Citrus medica is a potential, environmentally friendly biomass feedstock for renewable production of biodiesel using green NPs of copper oxide as catalyst.

Automated summary

The study investigated the potential of Citrus medica as a novel and non-edible seed oil producing feedstock for biodiesel production, using green and recyclable nanoparticles of copper oxide as catalyst.