Maricruz Juárez-García

This work presents the conceptual design, rigorous simulation, and multi-objective optimization of an integrated multiproduct biorefinery focused on the sustainable valorization of lignin into catechol and a portfolio of high-value aromatic derivatives, including guaiacol, vanillin, and vanillic acid. The proposed methodology combines a critical review of synthesis pathways and kinetic data with detailed process modeling in Aspen Plus® V14. The process framework begins with lignocellulosic biomass pretreatment via acid hydrolysis, followed by catalytic lignin depolymerization to obtain catechol as a platform intermediate. Subsequently, dedicated reaction and separation sections are designed for the selective conversion of catechol into value-added derivatives, incorporating energy-efficient and thermally integrated separation schemes. A stochastic multi-objective optimization strategy based on Differential Evolution with a Tabu List (DETL) is implemented to simultaneously assess economic and environmental performance indicators. The results demonstrate that lignin can be effectively upgraded into commercially relevant fine chemicals, confirming its strategic role within next-generation biorefineries and reinforcing the transition toward circular, low-emission chemical processes.