Economic and environmental performances of bio-based chemicals produced with green hydrogen as a reagent in a sugarcane biorefinery

While sugarcane biorefineries are extensively studied, their integration with green hydrogen (GH 2) for high-value biochemical production remains unexplored. This study presents the first comprehensive technoeconomic and environmental assessment of sugarcane biorefineries supplied with external GH 2, evaluating the impacts of hydrogen demand, cost, and emission factors. Lignin obtained via Reductive Catalytic Fractionation (RCF) was converted into cyclohexanol, cyclohexanone, phenol, and phenolic oligomers, while the cellulose-rich fraction was pyrolyzed to levoglucosenone and subsequently converted into dihydrolevoglucosenone (Cyrene™) or 1, 6-hexanediol (1, 6-HDO). Isomalt was produced from A-molasses via enzymatic biotransformation. All pathways were integrated with a sugarcane mill to ensure energy self-sufficiency. Economic feasibility was assessed using minimum selling prices (MSPs) at a 20% internal rate of return and a GH 2 price of 8/kg. MSPs for 1, 6-HDO (4, 021/ton), phenol (1, 286/ton), phenolic oligomers (1, 391/ton), isomalt (1, 180-1, 330/ton), and Cyrene™ (927/ton) were competitive with market prices, whereas cyclohexanone (2, 476/ton) and cyclohexanol (2, 886/ton) exceeded them due to GH 2 and downstream processing costs. High-pressure reactors accounted for 25-77% of equipment costs, and GH 2 represented 3-63% of operating costs; sensitivity analysis indicates that reducing GH 2 prices to 2-3/kg would improve competitiveness. Life-cycle carbon emissions for all bioproducts (0. 82-3. 01 kg CO₂-eq/kg product) were lower than fossil-based counterparts (3. 11-4. 15 kg CO₂-eq/kg product). Lignin-derived products had higher emissions due to solvent use, while sugar-derived pathways benefited from water- or solvent-free processes. Hydrogen-intensive biorefineries were sensitive to hydrogen inputs, causing variability in emissions and costs. These results demonstrate that integrating green hydrogen enables economically viable sugarcane biorefineries with substantially reduced carbon footprints, even at current GH 2 prices. • Chemicals produced with green hydrogen in sugarcane biorefinery. • Solvents for Reductive Catalytic Fractionation of lignin undesirable. • Improved environmental benefits for sugar-derived products. • Hydrogen cost reduces financial viability for bio-based chemicals.