Life Cycle Assessment and Economic Analysis of Integrated Biorefinery Processes for the Production of Catechols from Catechyl Lignin

Abstract

Catechyl lignin (C-lignin), composed solely of caffeyl alcohol units, features a linear and homogeneous structure, making it an “ideal lignin” archetype for the production of low-carbon catechols through catalytic depolymerization. In this study, we conducted life cycle assessments (LCA) and economic analyses of four biomass-based routes for catechols production from castor seed coats, relative to the conventional fossil-based route. The LCA predicts that biomass-based routes for catechols production exhibited significant advantages in global warming potential, ozone layer depletion potential, and photochemical oxidation potential, particularly with the DL process. Economic and carbon footprint analyses identified the DL route as the optimal process, delivering a low production cost of $2.17 per kilogram of catechols and a significant negative carbon footprint (-196.57 kg CO2). Sensitivity analysis of the DL route indicated that nitrogen fertilizer usage and electricity consumption were the most sensitive parameters affecting global warming potential, while variations in electricity consumption and dioxane usage had the most significant impact on economic costs. This contribution provides a novel pathway for catechols production via C-lignin depolymerization, expanding the possibility for replacement or supplement of the conventional fossil-based catechols.

Keywords: Catechyl lignin, Catechols, life cycle assessment, Economic analysis, Carbon footprint, Sensitivity analysis