A comprehensive review published in Separations by Eliézer Quadro Oreste, Krystopher Borges Krammer, Antunielle Schneider Arias, Rodrigo Gamarra Navarrete, Janaína Oliveira Gonçalves, Jean Lucas de Oliveira Arias, Karina Lotz Soares, Daiane Dias, Ednei Gilberto Primel, Anelise Christ-Ribeiro, and Sergiane Caldas Barbosa explores the application of biochar-based sorbents for extracting emerging organic contaminants from environmental matrices. The authors highlight that industrial and agricultural activities continuously release persistent micropollutants, such as pesticides, pharmaceuticals, plasticizers, and steroid hormones, into aquatic ecosystems. Traditional wastewater treatment plants are often incapable of removing these compounds, which typically present at trace or ultra-trace levels in complex sample backgrounds. To accurately isolate and measure these pollutants, analytical chemists are increasingly turning to biochar derived from agricultural waste, coconut shells, herbal residues, and seafood processing by-products. Thermochemical conversion and surface engineering, including chemical activation and magnetization, transform raw biomassBiomass is a complex biological organic or non-organic solid product derived from living or recently living organism and available naturally. Various types of wastes such as animal manure, waste paper, sludge and many industrial wastes are also treated as biomass because like natural biomass these More into carbonaceous materials with high specific surface areas, rich surface chemistry, and tunable porosity tailored for target analyte capture.

The performance findings synthesized in the review demonstrate that biochar-based sample preparation approaches yield exceptional quantitative results across diverse extraction formats, including magnetic solid-phase extraction, solid-phase microextraction, and rotating disk sorptive extraction. The evaluated methods achieve high analyte recoveries, reaching up to one hundred percent for target compounds such as nonsteroidal anti-inflammatory drugs and pesticides, alongside relative standard deviations well within acceptable precision limits. Furthermore, solid-phase microextraction configurations utilizing modified biochars deliver remarkable enrichment factors ranging up to several thousand-fold, enabling ultra-trace limits of detection down to sub-nanogram-per-liter levels. Incorporating magnetic iron oxides into the biochar matrix accelerates phase separation to under one minute without requiring centrifugation, while miniaturized techniques dramatically minimize organic solvent consumption. By replacing expensive synthetic resins with reusable biochar sorbents, these analytical advancements advance circular economy principles and support green analytical chemistry goals for environmental monitoring.

Source: Oreste, E. Q., Krammer, K. B., Arias, A. S., Navarrete, R. G., Gonçalves, J. O., Arias, J. L. O., Soares, K. L., Dias, D., Primel, E. G., Christ-Ribeiro, A., & Barbosa, S. C. (2026). Biochar-based sorbents for the extraction of emerging organic contaminants from environmental matrices: A review. Separations, 13(9), 257.