Synthesis and characterization of anthill-eggshell-Ni-Co mixed oxides composite catalyst for biodiesel production from waste frying oil

This study was conducted to develop a new composite heterogeneous catalyst, anthill-eggshell-Ni-Co mixed oxides (AENiCo), for biodiesel production via transesterification of waste frying oil. The catalyst was synthesized using a co-precipitation method and was characterized by Brunauer-Emmett-Teller (BET) surface area analysis, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray fluorescence (XRF). The effects of parameters affecting the catalytic reaction, reaction temperature (40-80 degrees C), reaction time (1-5 h), catalyst loading (1-9 wt%), and methanol-to-oil ratio (3:1-15:1) were investigated. The stability of the spent catalyst was also investigated during reuse. The data obtained showed that the maximum biodiesel yield of 90.23% could be obtained at a reaction temperature of 70 degrees C, reaction time of 2 h, with a catalyst loading of 3 wt% and methanol-to-oil ratio of 12:1. The stability study showed that the AENiCo catalyst could be reused for up to four cycles. (c) 2018 Society of Chemical Industry and John Wiley & Sons, Ltd