Sustainable Utilization of Biomass-Derived Biochar for Asphalt Modification: Multiscale Experimental and Theoretical Insights
Year: 2026
Type: preprint
Abstract: Wheat straw-derived biochar (WS-biochar), a sustainable carbon material produced from agricultural residues, represents a promising pathway for the valorization of biomass waste toward low-carbon infrastructure systems. However, the molecular mechanisms governing its interaction with asphalt binders remain insufficiently understood, particularly at the micro- and nanoscale where structural, chemical, and morphological features play key roles. In this study, WS-biochar was incorporated into PG 70 − 10 asphalt at varying loadings (0–10 wt%), and a combined experimental and density functional theory (DFT) approach was employed to investigate its effects on asphalt structure and properties. Comprehensive spectroscopic and nanoscale characterization (SEM, BET, XRD, Raman, FTIR, NMR, and AFM fast force mapping) revealed that moderate biochar content (4–6 wt%) enhances local aromatic ordering, reduces structural defects, and produces a more uniform nanoscale surface morphology and mechanical response. DFT calculations further demonstrated that WS-biochar strongly interacts with asphalt molecules through hydrogen bonding, π-π stacking, van der Waals forces, and charge-transfer-assisted polarization, significantly modulating electronic structures and increasing molecular polarity. These findings provide mechanistic insights into the reinforcing effects of WS-biochar and a scientific basis for the sustainable design of biochar-enabled infrastructure materials with improved performance and reduced environmental footprint.
Source: Research Square
Institution: University of Miami
Language: English
Subfield: Civil and Structural Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
Award: G6750390234
OpenAlex ID: W7160915073