Work

Ultrasound-Induced Embedded-Silica Migration to Biochar Surface: Applications in Agriculture and Environmental Sustainability

Year: 2025

Type: article

Abstract: Si-containing compounds, such as SiO2, are crucial for applications such as filler, binding phases, or linking agents. SiO2 coatings can improve the performance of biochar-based carbon negative fillers in sustainable materials like bioplastics, rubber, and asphalt, making them more competitive with conventional fillers. Biochar, derived from biomass contains a high concentration of SiO2, typically 50–80% of its total inorganic compounds. However, conventional methods for extracting biogenic SiO2 from biochar, such as solvent extraction or gasification, detach SiO2 from the biochar structure. This study explores an alternative approach to induce the micro-migration of biogenic SiO2 from within biochar to its surface, without detaching from the structure. Biochar samples of five different biomass resources; sugarcane bagasse, miscanthus, wheat straw, corn stover, and railroad ties produced at 650ºC, 750ºC, and 850ºC, were subjected to ultrasound waves in IPA-water mixture. SEM and EDS analyses confirmed that ultrasound treatment effectively induced migration of biogenic SiO2 from within the biochar to its surface, with the maximum SiO2 observed on the surface of the biochar synthesized at 850ºC. FTIR analysis revealed that ultrasound treatment also altered some functional groups, which could be present both within the structure and on the surface.

Source: Sustainability

DOI: 10.3390/su172310813

Authors: Muhammad Abdullah, Shanza Baig, Maria Paula Silva Martinez, Baharak Sajjadi

Institution: University of Oklahoma

Language: English

Topic: Thermochemical Biomass Conversion Processes

Subfield: Biomedical Engineering

Field: Engineering

Domain: Physical Sciences

SDGs: Responsible consumption and production, Affordable and clean energy

Open Access status: gold

Estimated APC paid: $2,896