Biodiesel Production from Refined Rice Bran Oil Using Eggshell Waste As Catalyst Impregnated with Silver Nanoparticles

Biodiesel is a promising renewable fuel with many attractive features such as high combustion efficiency, biodegradability, and less toxic exhaust emission. This study investigated an environmentally friendly method for biodiesel production from refined rice bran oil (RRBO) using calcium oxide (CaO) from eggshell waste as a catalyst via transesterification reaction. A two-level three-factor full factorial experimental design was used to determine the effect of the impregnation of silver nanoparticles (AgNPs), calcination temperature and heating rate as independent variables on the biodiesel yield. Results showed that the calcination heating rate and the impregnation of AgNPs had significant effects on the biodiesel yield. An optimum biodiesel yield of about 92% was obtained using AgNPs impregnated CaO catalyst prepared from eggshell waste using a heating rate of $5^{\circ}\displaystyle \mathrm{C}/\min$ during calcination at temperatures in 800-$1000^{\circ}\mathrm{C}$ range.