ABSTRACT

Biodiesel yield is generally reduced by the high concentration of free fatty acid and moisture from waste cooking oil. The synergetic impact of the biomass catalysts from the base as well as the acid source was used to address this problem of FFA and moisture content. A biologically-based acid-base functional catalyst (ABFC) was produced with wet impregnation technique using the combination of sulfonated rubber seed shell bio char (SRSS-BC) and calcined egg shell (C-ES). The ABFC was characterized using X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscope (SEM), and Fourier Transform Infrared (FTIR) spectroscopy. BET results showed a surface area of 141m²/g, a pore size of 2.132nm, and a pore volume of 0.0888cc/g. The catalytic activity of waste cooking oil (WCO) in simultaneous esterification and transesterification with a high initial free fatty acid content of 33.217 mgKOH/g was analyzed with process parameters adjusted utilizing response surface methodology (RSM).