title: Catalytic Oxidation of Phenol and 2,4-Dichlorophenol by Using Horseradish Peroxidase Immobilized on Graphene Oxide/Fe₃O₄.
abstract: Graphene oxide/Fe₃O₄ (GO/Fe₃O₄) nanoparticles were synthesized by an ultrasonic-assisted reverse co-precipitation method, and then horseradish peroxidase (HRP) was covalently immobilized onto GO/Fe₃O₄ with 1-ethyl-3-(3-dimethyaminopropyl)carbodiimide (EDC) as a cross-linking agent. In order to enhance the phenol removal efficiency and prevent the inactivation of the enzyme, the polyethylene glycol with highly hydrophilicity was added in this reaction, because the adsorption capacity for the polymer by degradation was stronger than the HRP. The results showed that the immobilized enzyme removed over 95% of phenol from aqueous solution. The catalytic condition was extensively optimized among the range of pH, mass ratio of PEG/phenol as well as initial concentration of immobilized enzyme and H₂O₂. The HRP immobilized on GO/Fe₃O₄ composite could be easily separated under a magnetic field from the reaction solution and reused.
authors: College of Resources and Environmental Science, South Central University for Nationalities, Wuhan 430074, China. changqinghust@163.com.
authors: Qing
authors: Q
authors: Chang
authors: College of Resources and Environmental Science, South Central University for Nationalities, Wuhan 430074, China. jjhhhust@163.com.
authors: Jia
authors: J
authors: Huang
authors: College of Resources and Environmental Science, South Central University for Nationalities, Wuhan 430074, China. dyaobin@126.com.
authors: Yaobin
authors: Y
authors: Ding
authors: College of Resources and Environmental Science, South Central University for Nationalities, Wuhan 430074, China. tangheqing@mail.scuec.edu.cn.
authors: Heqing
authors: H
authors: Tang
mesh_terms: D002384:Catalysis; D002733:Chlorophenols / Q000737:chemistry*; D004800:Enzymes, Immobilized; D005290:Ferric Compounds / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D006735:Horseradish Peroxidase / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry; D058185:Magnetite Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D010084:Oxidation-Reduction; D010636:Phenols / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D002733:Chlorophenols; D004800:Enzymes, Immobilized; D005290:Ferric Compounds; D058185:Magnetite Nanoparticles; D010636:Phenols; C000499:ferric oxide; D011092:Polyethylene Glycols; D006108:Graphite; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase; C004762:2,4-dichlorophenol
keywords: catalytic oxidation; graphene oxide; immobilized enzyme; magnetite; phenol