Optimization of Methanolysis of Used Cooking Oil by the Taguchi Experimental Design Approach

Abstract

The goal of this study was to look into the catalytic activity of KOH‐modified CaO from eggshell as catalyst for the optimization of biodiesel production from used cooking oil (UCO), applying the Taguchi approach. The strong base catalyst (K/CE) was formulated by doping KOH on calcined chicken eggshell at various quantities (0–2.5 g), where 2 g of KOH doped on 5 g of calcined eggshell (2K/CE) and recalcined at 400 °C was found to represent the best catalyst formulation conditions. The optimal catalyst resulted in the maximum UCO biodiesel (UCOB) yield of 91.92 % at 70 °C for 1 h, using a 2K/CE dosage of 0.5 wt % and a methanol/UCO molar ratio of 15:1. The physicochemical properties of the optimal UCOB sample were in accordance with ASTM D6751 specifications, and gas chromatography‐mass spectrometry analysis confirmed the presence of methyl esters at an amount of 97.65 wt %.