Correlation between biodiesel parameters and output of CaO nanoparticles from oyster catalyst on waste cooking oil

Waste oyster shells and waste cooking oil (WCO) were used to develop biodiesel, which may be less expensive than fossil fuels. The effect of %catalyst, reaction temperature, ratio of WCO to methanol, and reaction time were experimentally determined using Taguchi-grey (GRA) multi-response analysis. The percentage biodiesel yield, acid number, and water and sediment content were selected as the multi-response. The results suggest an ideal point of 1.5% catalyst, 60 °C reaction temperature, 1:9 oil-to-methanol ratio, and contact time of 6 h to produce 96% biodiesel yield, 0.48 mg KOH/g acid number, and 0.032 vol% water and sediment content. At a 95% confidence level, the projected GRA was fairly close to the experimental GRA. This demonstrated that the optimal processing parameters found were successful. Waste oyster was revealed to be capable of transesterifying WCO, resulting in higher biodiesel yield, reduced acid number, and less water and silt.