Comparative Study of Production of Biodiesel Utilizing Calcinated Eggshell and Immobilized Lipase-Eggshell Catalysts by Waste Cooking Oil, Catalysts Characterization and Yield Optimization

Abstract

Due to the high demand, cost and environmental toxicity of fossil fuels, mainly petroleum and diesel, there is a massive demand for alternative fuels based on biological origin. The production of biodiesel from cheap resources has gained more attention. Present study conducted biodiesel production from waste cooking oil utilizing calcinated eggshells and immobilized lipase. The eggshell was calcinated at temperature ranges from 500-800 ºC and characterized by TGA, SEM, XRD and FTIR analysis; the study of characteristics of calcinated eggshell was helpful in the production of biodiesel, it is around ~42% yield production achieved at 60 ºC, 1000 rpm revolution of stirrer for O/A (oil/alcohol) molar ratio 1:6. Now the lipase of activities 40 μ/g immobilized with eggshell, the eggshell-lipase catalyst (ELC) gives the yield of ~92% at 40 °C, 500 rpm revolution of stirrer and O/A molar ratio 1:6 after transesterification process on waste cooking oil (WCO) with calcined eggshell and reusability application of ELC. The production of biodiesel by immobilized catalyst at a higher temperature will reduce the thermal stability of lipase. To get the maximum biodiesel yield, the transesterification process must undergo at an optimum higher temperature. This is overcome by immobilizing the commercial lipase with an eggshell that can withstand even higher temperatures (40-45 ºC) without losing its activities. The processes and optimization are globally integrated to improve the feasible evaluation of economic improvement for biodiesel production.