Evaluation of the effectiveness of the optimization procedure with methanolysis of waste oil as case study

Abstract

Local white stone (LWS) identified as Brette Pearl Spar Mable was used to catalyze the transesterification of waste used oil (WUO) to waste used oil biodiesel (WUOB) in the presence of methanol acting a solvent. The conversion of WUO to WUOB was monitored by calcinated LWS (CLWS). Analysis of CLWS demonstrated that potassium (K) is the major active component responsible for the activity of the catalyst in CLWS synthesis, and the transesterification of WUO to WUOB in the presence of methanol shows the catalyst to be suitable for biodiesel production from WUO. To model and optimize the process condition, response surface methodology and Artificial Neural Network was employed in the conversion of WUO to WUOB using CLWS as heterogeneous base catalyst. The modeling was carried out by considering three factors, reaction time (RT), catalyst amount (CA) and the ratio of methanol/oil (M/OR). The optimum conditions that achieved 92.45 (%w/w) for RSM and 98.46 (%w/w) for ANN were RT of 40 min, CA of 6 g and M/OR of 5.5:1. Characterization of the produced WUOB shows that the WUOB can replace conventional diesel when blends. Nevertheless, statistical analysis showed that the conversion using presoaked CLWS, proved to be a suitable heterogeneous catalyst for transesterification of biodiesel.