The use of biochar has gained popularity for its multifunctional applications in agriculture and environmental settings. In this study, a novel type of biochar was prepared using raw biochar derived from parthenium weed through electrolysis and chemical co-precipitation with Fe2+. The resulting electromagnetic biochar had an increased surface area, magnetism, and modified surface chemistry due to the formation of iron oxide minerals (magnetite and hematite). As a result, it exhibited a 73% higher capacity for adsorbing Cd from industrial wastewater than raw biochar. The maximum adsorption of Cd occurred after 120 min, and the adsorption kinetics were best described by the pseudo-second-order model and Elovich model based on AIC values, suggesting chemical interactions between the electromagnetic biochar and Cd, such as chelation. Furthermore, the electromagnetic biochar remained highly stable in strongly acidic and alkaline aquatic environments, indicating its potential as an effective Cd-removal tool. Overall, this study highlights the promise of electromagnetically modified biochar for the removal of Cd from industrial wastewater.
