Life cycle assessment of waste cooking oil for biodiesel production using waste chicken eggshell derived CaO as catalyst via transesterification

There are plentiful experimental studies on biomass as heterogeneous catalyst and its reasonable cost, it can be a potential catalyst feedstock for biodiesel production. This study presents the life cycle assessment (LCA) of waste cooking oil biodiesel production catalyzed by waste chicken eggshell derived CaO catalyst to validate the suitability of waste chicken eggshell as a green catalyst in biodiesel field. To the best of our knowledge, LCA was first performed for the heterogeneous catalyst, CaO preparation as a subsystem in a biodiesel production. Comparative studies were performed to evaluate the difference of environmental impacts contributed by waste cooking oil, WCO biodiesel production catalyzed by waste chicken eggshell derived CaO with the two different production processes via Jatropha oil as the oil feedstock and potassium hydroxide, KOH as the homogeneous catalyst. Utilization of WCO as the oil feedstock for biodiesel production has lesser environment impact than the Jatropha oil as the WCO biodiesel production does not involve agriculture phase. Likewise, utilization of waste chicken eggshell derived CaO catalyst (heterogeneous catalyst) has less contribution on the overall impact categories than KOH (homogeneous alkali-based catalyst) as the production of KOH required addition of chemical and additives, plus complex purification and neutralization processes are required during the production phase. The overall impact results clearly indicated the best environmental performance of waste chicken eggshell derived CaO of 1.17 Pt was over the traditional KOH catalyst and implementation of Jatropha oil but also identified some bottlenecks that should be addressed for more sustainable solutions.