In this study, we explore a sustainable approach to repurposing eggshell waste as a catalyst for the conversion of biomass-derived sucrose, sugar syrup, xylan, and cellulose into lactic acid, a chemical in high demand. Currently, lactic acid is industrially produced using lactic acid bacteria (LAB), which require precise pH control and temperature maintenance, complicating their application. Our work demonstrates a one-pot synthesis of lactic acid using calcined eggshells in an aqueous medium via simple thermal treatment. Comprehensive characterization of the eggshell catalyst was carried out using techniques such as XRD, BET, FT-IR, FE-SEM, XPS, and TGA, revealing that calcination above 700 degrees C transformed the eggshell into CaO, drastically altering its morphology and enhancing its basicity. At 200 degrees C, using 70 wt% of catalyst for 1 h, we achieved a remarkable 92 C-mol% lactic acid yield with excellent carbon balance. The increased basicity played a key role in selectively driving lactic acid production. Our approach offers a green, sustainable solution with significant implications for future research in valorizing waste materials and advancing bio-based chemical production.

Foreign