Life cycle assessment of biodiesel production using a nonionic surfactant and CaO from eggshell as a catalyst.

Life cycle assessment (LCA) is a tool used to evaluate the environmental impacts and resources used to manufacture a product. The present study proposes an innovative and unprecedented based on LCA of biodiesel production from the methyl transesterification of soybean oil catalyzed by eggshell-derived CaO and using the nonionic surfactant nonylphenol ethoxylate (NP6EO). Biodiesel was produced under mild conditions with a 1:4 methanol-to-oil ratio, 2 wt% CaO, 1 wt% NP6EO, and reaction times of 2 hours with surfactant and 3 hours without, with a yield of 95.18% and 97.75%, respectively. The life cycle impact assessment (LCIA) was performed using the SimaPro software and the Ecoinvent 3.6 database by implementing the CML-IA baseline method. Results indicated that the catalyst preparation process had the lowest environmental impact, while soybean oil used contributed the most across all impact categories. The surfactant-based process was 77% more eco-efficient than the non-surfactant process. Results also showed that surfactant concentration has more influence on impacts than additional electricity consumption due to a longer reaction time. Compared to traditional KOH-catalyzed biodiesel production, the use of CaO from eggshells and NP6EO demonstrated a lower environmental impact, suggesting this method is a promising alternative to conventional processes. [ABSTRACT FROM AUTHOR]