标题：Fe3O4@β-CD nanocomposite as heterogeneous Fenton-like catalyst for enhanced degradation of 4-chlorophenol (4-CP)
作者：Wang, Manlin ;Fang, Guodong ;Liu, Peng ;Zhou, Dongmei ;Ma, Chen ;Zhang, Dongju ;Zhan, Jinhua
作者机构：[Wang, Manlin ;Liu, Peng ;Ma, Chen ;Zhang, Dongju ;Zhan, Jinhua ] Key Laboratory for Colloid and oInterface Chemistry of Education Ministry, Departmen 更多
来源：Applied Catalysis B: Environmental
摘要：The magnetic Fe3O4@β-cyclodextrin (β-CD) nanocomposites were fabricated via Fe ions and β-CD in one pot and characterized as a heterogeneous Fenton-like catalyst that may be used for the degradation of 4-chlorophenol (4-CP). The catalytic capacity of Fe3O4@β-CD was evaluated on the basis of various parameters, including pH, H2O2concentration and catalyst loading, with regards to the pseudo-first-order kinetics of 4-CP degradation. In addition, iron leaching, the effect of radical scavengers and reusability of the Fe3O4@β-CD nanocomposite were also studied. The results showed that Fe3O4@β-CD exhibited a higher catalytic ability than that Fe3O4toward 4-CP degradation, the observed rate constants (kobs) were 0.0373 min-1for Fe3O4@β-CD, and 0.0162 min-1for Fe3O4, which may be ascribed to the construction of a ternary complex (Fe2+-β-CD-pollutant) that allowed the produced hydroxyl radicals (·OH) to directly attack the contaminant and simultaneously enhanced the solubility of the organic pollutant. Fe3O4@β-CD also exhibited an enhancement effect for chlorobenzene (CB) degradation with the kobsof 0.0392 min-1(kobs= 0.0099 min-1for Fe3O4), which may be due to a synergistic effect in the Fe3O4@β-CD composite. Furthermore, Fe3O4@β-CD has an excellent catalytic activity, stable mechanical strength and adequate reusability. A possible reaction pathway of 4-CP degradation dominated by ·OH was proposed according to analyses of the degradation intermediates and chloride ions. The host-guest interaction between β-CD and 4-CP were examined with density functional theory (DFT) calculations, expounding the unicity of degraded intermediate owing to the specific spatial selectivity of β-CD. The findings of this study provide a novel material used in the Fenton-like process for the degradation of contaminants.
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