Suarez-Velázquez, G.G.; Lugo-Lugo, V.; Meléndez-González, P.C.; Pech-Rodríguez, W.J.: Carbon derived from citrus peel waste: advances in synthesis methods and emerging trends for potential applications - a review. Biomass Conversion and Biorefinery 15 (2025), p. 30705-30731
10.1007/s13399-025-06889-8
Abstract:
Agroindustrial waste poses serious threats to soil, water reservoirs, and human health due to the large amount produced daily. In this context, the review explores the valorization of citrus peel (CP) waste by converting it into biochar, highlighting recent advancements in carbon fabrication and activation while discussing their respective strengths and limitations. Moreover, it identifies reported applications of carbon derived from CP where metal and organic structures, such as CoTe, Pt, and TiO2-Fe2O3, have been incorporated to enhance performance in energy storage, water remediation, and sensing. For example, in supercapacitor applications, it was observed that CP-derived carbon can deliver a specific capacitance of 460 F g−1, which is comparable to other biomass-derived carbons. Furthermore, it has demonstrated excellent performance in water treatment, achieving a sorption capacity of 2342.91 mg g−1 for methyl orange and a removal efficiency of 99.39% for pharmaceutical pollutants like metformin. Other noteworthy applications include its use in sensing, particularly for detecting Al3+ species with a detection limit of 0.695 μmol L−1 as well as for sulfonated derivatives of salicylaldehyde S1, which have a detection limit of 0.87 μmol L−1. The importance of this research lies in its ability to guide the selection of the optimal path for developing biocarbon according to specific requirements such as specific surface area, pore size, and electrical conductivity. By exploring the valorization of CP waste, this study also contributes to the principles of a circular economy, where waste is transformed into valuable products, reducing environmental impact. Thus, the insight gained from this investigation can assist practitioners and young researchers in visualizing the potential uses of biochar derived from CP in emerging technologies, thereby enhancing the value of agroindustrial by-products.