Multi-product biorefinery with sugarcane bagasse: Process development for nanocellulose, lignin and biohydrogen production and lifecycle analysis

Sugarcane processing sector generates large quantities of sugarcane bagasse (SCB) as the residual lignocellulosic biomass (similar to 30% by weight). With its rich biochemical composition, SCB can function as potential, renewable, and alternative feedstock for high valued biobased products in the framework of circular economy. Production of nanocrystalline cellulose (NCC) from SCB, integrated with co-production of lignin and biohydrogen in a biorefinery approach was studied. Pretreatment of SCB resulted in the extraction of cellulose (0.34 +/- 0.02 g/g) followed by NCC production (0.15 +/- 0.02 g/g SCB) through depolymerization. In the biorefinery scenario, 0.15 L/g COD E of H-2, and 0.15 +/- 0.05 g/g SCB of lignin was produced in addition to NCC. The products were characterized for their respective qualitative and quantitative recoveries. Further, standalone NCC production and biorefinery processes were compared for their sustainability by employing lifecycle impact assessment (LCA) tool. The biorefinery scenario has depicted nearly 30% less environmental impacts along with 24% less CO2 emissions (GWP) than the standalone process. Sensitivity analysis validated the data precision with repeatability and reproducibility of the results. Establishment SCB based biorefinery process with zero liquid discharge (ZLD) approach provides additional benefits to the sugarcane processing industries by infusing circular chemistry in the industry 4.0 framework.

Automated summary

This study highlights the potential of sugarcane bagasse as a renewable feedstock for producing high-value biobased products through biorefinery processes. The integrated production of nanocrystalline cellulose, lignin, and biohydrogen from sugarcane bagasse showed promising results with reduced environmental impacts and CO2 emissions compared to standalone processes.