▎ 摘 要
Schwertmannite (sch), an iron oxyhydrosulfate mineral, can catalyse a Fenton-like reaction to degrade organic contaminants, but the reduction of Fe(III) to Fe(II) on the surface of schwertmannite is a limiting step for the Fenton-like process. In the present study, the sch/few-layer graphene (sch-FLG) composite was synthesized to promote the catalytic activity of sch in a Fenton-like reaction. It was found that sch can be successfully carried by FLG in sch-FLG composite, mainly via the chemical bond of Fe-O-C on the surface of sch-FLG. The sch-FLG exhibited a much higher catalytic activity than sch or FLG for the degradation of sulfamethazine (SMT) in the heterogeneous Fenton-like reaction, which resulted from the fact that the FLG can pass electrons efficiently. The degradation efficiency of SMT was around 100% under the reaction conditions of H2O2 200-500 mg l(-1), sch-FLG dosage 1-2 g l(-1), temperature 28-38 degrees C, and initial solution pH 1-9. During the repeated uses of sch-FLG in the Fenton-like reaction, it maintained a certain catalytic activity for the degradation of SMT and the mineral structure was not changed. In addition, SMT may be finally mineralized in the Fenton-like reaction catalysed by sch-FLG, and the possible degradation pathways were proposed. Therefore, the sch-FLG is an excellent catalyst for SMT degradation in a heterogeneous Fenton-like reaction.