Preparation and characterization of potato peel derived hydrochar and its application for removal of Congo red: a comparative study with potato peel powder

This study aimed to investigate the potential of potato peel waste powder as a biomass feedstock for hydrothermal carbonization to produce hydrochar, which could be used as an adsorbent for water treatment. An autoclave was used at 200 °C for 25 h to prepare potato peel hydrochar from potato peel waste powder and compared their physicochemical properties using various characterization techniques. The results showed that potato peel hydrochar had a higher specific surface area and adsorption capacity for Congo red than potato peel waste powder, making it a viable adsorbent for water treatment. The experimental data were well-fitted with the Freundlich isotherm and pseudo-second-order kinetic models suggesting that the adsorption process at the solid/solution interface is spontaneous, endothermic, and more disordered. The study highlights the potential of waste biomass, such as potato peel, to produce hydrochar as an effective and sustainable adsorbent for water treatment. Graphical abstract