Peculiarities of bio-oil and biochar obtained from the lignin-rich residue of the enzymatic hydrolysis of sugarcane bagasse

Author(s)

Gomes, Gustavo R. ; de Jesus, Ester G. ; Jacintho, Jaqueline C. C. ; Garcia, Diana L. G. ; Alencar, Barbara R. A. ; Gabetto, Fernanda P. ; Gomes, Joice J. ; Carvalho, Joao L. N. ; Strauss, Mathias ; Driemeier, Carlos

• Document type: Journal article
• Source: RENEWABLE ENERGY; v. 241, p. 10-pg., 2025-01-09.

Abstract

In the quest for sustainable energy and climate solutions, this work investigates the pyrolysis of the lignin-rich enzymatic hydrolysis residue (EHR), a feedstock available at scale in the nascent cellulosic ethanol industry. The uniqueness of EHR was investigated by a systematic series of feedstocks, submitting sugarcane bagasse to steamexplosion pretreatment followed by carbohydrate enzymatic hydrolysis. The solid biomass of each process step (raw, pretreated, and EHR) was pyrolyzed (450 degrees C, 30 min, fixed bed reactor), followed by comprehensive characterization of bio-oil (FTIR, NMR, GPC, and GC-MS) and biochar (SEM, XPS, Raman, and TGA), and biochar stability and application assays (methylene blue adsorption and soil greenhouse gas emissions). EHR bio-oil was less oxygenated (mainly through lower carboxyl content) and slightly enriched in aromatics. EHR biochar was less oxygenated, more graphitic, and more stable (mechanically and thermally). These are favorable traits for fuels and chemicals from bio-oil and carbon removal with biochar. Nevertheless, EHR biochar applications showed lower dye adsorption and higher nitrous oxide emissions from biochar-treated soils. These findings demonstrate that EHR pyrolysis is a promising pathway to expand biomass carbon utilization and instigate further research to optimize EHR pyrolysis and enhance the functionality of EHR biochar for agri-environmental applications. (AU)

• FAPESP's process: 14/50884-5 - INCT 2014: National Institute of Science and Technology of Bioethanol
• Grantee: Marcos Silveira Buckeridge
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 16/50403-2 - Valorizing the decentralized biomass production chain for advanced biofuel production: development and evaluation of thermochemical routes integrated with biomass production and biochemical routes
• Grantee: Antonio Maria Francisco Luiz Jose Bonomi
• Support Opportunities: Research Grants - Research Partnership for Technological Innovation - PITE
• FAPESP's process: 21/13455-2 - Depolymerization of residual lignins from cellulosic ethanol: towards a novel platform for renewable chemicals
• Grantee: Gustavo Rodrigues Gomes
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 23/01468-8 - Understanding the specificities of bio-oils and biochars obtained from the residual lignins of cellulosic ethanol
• Grantee: Carlos Eduardo Driemeier
• Support Opportunities: Regular Research Grants