Production of biodiesel from Aspergillus terreus KC462061 using gold-silver nanocatalyst

Abstract

The current study aims to guarantee eco-friendliness, maximize production, and reduce biodiesel production costs using the new oleaginous fungus Aspergillus terreus KC462061 in the presence of gold-silver core–shell nanoparticles (Au@Ag NPs) as heterogeneous nanocatalysts in the process of biodiesel production. The response surface method (RSM) was used to optimize the production of Au@Ag NPs as heterogeneous nanocatalysts by A. terreus KC46206, supported by ANOVA, to validate the optimal conditions. Au@Ag NPs were characterized using UV-visible spectroscopy (UV-Vis), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). The process of biodiesel production was optimized by RSM and validated using ANOVA. The maximum biodiesel yield was 43.28% at the optimum conditions of a methanol/oil ratio (4:1), amount of nanocatalyst (1.0 wt.%), reaction temperature (40 °C), reaction time (4.0 h), and shaking speed (600 rpm). The template of fatty acid methyl esters (FAME) in biodiesel displayed significantly higher saturated fatty acids (SFAs) than unsaturated fatty acids (USFAs). The quality of the biodiesel was evaluated, and it was discovered that it met the criteria established by the global specifications, especially in the United States and Europe.

Keywords

• Biodiesel
• Aspergillus terreus
• gold-silver nanocatalyst
• optimization
• response surface method (RSM)