Sawdust-Based Hydrochar Shows Promise for Cleaning Food Processing and Dye Wastewater

Researchers have developed a sawdust-based material called MAHC that can adsorb methylene blue dye and treat real potato processing wastewater. The material is made through hydrothermal carbonization and activation with iron and copper, giving it a high surface area of 1,266 m²/g and a maximum adsorption capacity of 1,635 mg/g for the dye. In continuous flow tests, the material treated dye solution for 165 minutes and real wastewater for 360 minutes before breakthrough. The study, published in Sustainable Carbon Materials, tested the hydrochar in both batch and fixed bed column setups. The material works through pore filling, metal site interactions, and pi-pi bonding rather than just electrostatic attraction. The authors say more work is needed on room temperature performance, recyclability, and comparison with commercial activated carbon before industrial use. This research points to a waste-to-resource strategy where low-value sawdust becomes a functional water treatment material. For food processors and textile manufacturers, it could offer a lower-cost, circular alternative for managing difficult wastewater streams.