Mushroom residue derived magnetic hydrochar for antimony removal from wastewater: Mechanisms insights and practicality assessment

The magnetic mushroom residue hydrochar (MMRH) was synthesized using mushroom waste and K2FeO4, and then applied for antimony (Sb) removal from wastewater. The maximum adsorption capacity of Sb(III) and Sb(V) by MMRH reached 636.9 and 814.3 mg/g, respectively. According to characterizations, the existence of K+ in MMRH significantly increased the ion exchange of Sb species. Further, the Fenton-like reactions could generate additional •OH species to effectively oxidize Sb(III) into Sb(V), while other mechanisms including complexation, co-precipitation, and physical adsorption were also comprehensively investigated. The practicality of this MMRH was also assessed by recycling and column experiments. This study is expected to offer novel perspectives on mushroom residue reutilization and Sb-polluted wastewater purification for a greener environment.