Influence of acid hydrolysis on properties of cellulose nanofibers from wolf fruit peels (Solanum lycocarpum A. St.-Hill)

This study explores the use of wolf fruit peel as a sustainable source for producing cellulose nanofibers (CNFs). By valorizing this agricultural byproduct, the research contributes to the circular economy and reduces environmental impact, offering a high-value material with potential for composite reinforcement. The chemical treatment effectively purified cellulose by removing amorphous compounds, yielding nanometer-scale cellulose fibers. Acid hydrolysis using different concentrations of H₂SO₄ (0.1, 1, and 10% v/v) was essential for CNF production, enabling efficient isolation. Approximately 50% of hemicellulose and lignin were removed, as confirmed by FTIR analysis. However, higher H₂SO₄ concentrations (≥ 1%) damaged cellulose crystals by attacking both amorphous and crystalline regions, reducing the crystallinity index. CNFs obtained with lower H₂SO₄ concentrations exhibited enhanced stability, reduced aggregation, and thermal stability around 145 ºC, indicating their suitability for biopolymer reinforcement. This study introduces an innovative and sustainable approach to utilizing local biomass for developing new materials.