Sustainable Production and Comparative Liquid Phase Exfoliation of Onion Peel-Doped Sugarcane Bagasse Hybrid Biochar

Liquid-phase exfoliation offers a promising avenue for enhancing biochar properties and applications, addressing the scalability and cost concerns prevalent in alternative methods. A pivotal step in enriching sugarcane bagasse composition with both organic and elemental components involves the incorporation of onion peel, significantly expanding its potential applications in biochar production. This study focuses on producing hybrid biochar by blending sugarcane bagasse and chicken feathers, followed by liquid-phase exfoliation via two routes: acid and acetone. Elemental analysis revealed enrichment in the hybrid biochar due to the combined feedstocks. Nitric acid exfoliation increased oxygen and nitrogen content, while acetone preserved carbon content. Textural analysis showed substantial surface area enhancements in exfoliated samples (970.2 m²/g for acid and 903.1 m²/g for acetone, compared to 471.3 m²/g for hybrid biochar). Acetone exfoliation notably increased total pore volume. Microscopic surface investigation revealed layered, expanded structures in exfoliated biochar samples. The functional group analysis of the hybrid biochar revealed a diverse array of functional groups derived from both feedstocks, enhancing its potential versatility. Exfoliation induced significant chemical changes and peak shifts. This study underscores feedstock composition and exfoliation methods' roles in sustainable, high-quality biochar production.