BIODIESEL SYNTHESIS FROM NEEM SEED OIL USING GOAT BONES AND CORN COBS AS A NOVEL BIFUNCTIONAL CATALYST: OPTIMIZATION BY TAGUCHI APPROACH

ABSTRACT

This research focused on optimizing biodiesel production using Neem Seed Oil (NSO) with a novel bifunctional catalyst. The optimization was achieved through simultaneous esterification and transesterification of NSO employing the Taguchi L9 Method. The novel bifunctional catalyst was prepared by carbonizing and sulphuring corncobs to produce an acidic site of the bifunctional catalyst, while Goat Bones underwent calcination and treatment with KOH to create the basic site of the bifunctional catalyst. These two sites were subsequently impregnated to form the bifunctional catalyst. Characterization involved various techniques, including SEM, TGA/DTGA, EDXRF, XRD, FTIR, BET/BJH. To optimize simultaneous esterification and transesterification of NSO, the Taguchi L9 Method was employed. The catalyst's commercial viability was evaluated through a reusability test. Under optimized conditions, the test was conducted for five consecutive runs, examining its impact on NOB yield and Acid Value, with the catalyst being washed and reused. The yield of Neem oil biodiesel (NOB) and acid value (AV) were the measured responses. The optimum condition of this study was found to be 12:1 methanol to oil ratio, 3 wt.% catalyst loading, 60 °C, and 60 min of reaction time, obtaining a NOB yield of 85.578 wt.% and AV of 0.354 mg KOH/g. Among the variables, the methanol-to-oil molar ratio and duration had the greatest impact on NOB yield, but the catalyst loading and temperature had the most impact on NOB AV. The NOB's physiochemical properties met the ASTM D6751 and EN 14214 requirements for biodiesel upon characterisation of the NOB obtained at optimum conditions.