Sustainable poplar biorefinery producing butanol-rich solvents, furfural, and lignin-derived compounds with environmental and economic benefits
Meysam Madadi, Maryam Saleknezhad, Seyed Sajad Hashemi, Ehsan Kargaran, Mehdi Abbasi-Riyakhuni, Di Cai, Anushree Priyadarshini, Mahdy Elsayed, Chihe Sun, Fubao Sun
Abstract
The transformation of poplar biomass into bio-based chemicals, fuels, and lignin-derived products through an integrated biorefinery is essential for realizing its full potential as a sustainable and economically viable feedstock. This study presents a poplar biorefinery approach using mild biphasic pretreatment (p-toluenesulfonic acid/pentanol + AlCl3, 110°C, 40 min) to produce bio-based platform multiple products. The pretreatment achieved efficient fractionation, with 83.2% delignification, 95.2% xylan removal, and minimal cellulose loss (7.8%), enabling high-yield one-pot furfural production (68.5%, 11.3 g/L). Enzymatic hydrolysis of the cellulose-rich residue, combined with fermentation by Clostridium acetobutylicum, produced a bio-solvent mixture of 16.2 g/L, including 10.5 g/L butanol. Depolymerized lignin was recovered and subjected to catalytic hydrogenolysis, yielding 46.4% monomers, 9.3% dimers, and 17.4% oligomers. Processing 140 Mt of poplar biomass annually at scale could deliver substantial environmental and economic gains, avoiding approximately 64.12 Mt of CO2-eq emissions and generating an estimated USD 2.97 billion in annual socioeconomic benefits. Sensitivity analysis confirmed biomass availability as the dominant factor influencing emission reduction. Economic evaluation demonstrated strong financial viability, with an aggregate net present value of USD 65.7 billion projected for full national implementation. This work establishes a holistic and economically compelling biorefinery strategy for the sustainable production of bio-based chemicals and fuels.