Catalytic synthesis of biodiesel from waste cooking oil and corn oil over zirconia-based metal oxide nanocatalysts

Abstract

In the present study, ZrO2–SrO2 and ZrO2–CuO mixed oxides with different molar ratios were synthesized via Pechini sol–gel and co-precipitation methods and their catalytic activities were examined for biodiesel production from cheap raw feedstocks. The molar ratio of the prepared mixed oxide nanocatalysts were optimized through examining the effect of different molar rations in the catalytic transesterification of waste cooking oil (WCO) and corn oil. The structural and compositional characterization of as-prepared nanocatalysts were performed using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) techniques. According to the experimental results, the optimal catalytic performance of the prepared ZrO2–SrO2 and ZrO2–CuO mixed oxides was observed at Zr/Sr and Zr/Cu molar ratios = 2/1, temperature = 120 °C, methanol/oil molar ratio = 10/1 and reaction time = 3 h. The results indicated that the new prepared zirconia-based binary mixed oxides are suitable catalysts to produce biodiesel from waste cooking oils (WCOs) and corn oil, applicable to diesel engines.