Nitrogen-Doped Reduced Graphene Oxide as a Bifunctional Material for Removing Bisphenols: Synergistic Effect between Adsorption and Catalysis.
Nitrogen modified reduced graphene oxide (N-RGO) was prepared by a hydrothermal method. The nitrogen modification enhanced its adsorption and catalysis ability. For an initial bisphenol concentration of 0.385 mmol L(-1), the adsorption capacity of N-RGO was evaluated as 1.56 and 1.43 mmol g(-1) for bisphenol A (BPA) and 1.43 mmol g(-1) for bisphenol F (BPF), respectively, both of which were about 1.75 times that (0.90 and 0.84 mmol g(-1)) on N-free RGO. N-RGO could activate persulfate, producing strong oxidizing sulfate radicals. The apparent degradation rate constant of BPA on N-RGO was 0.71 min(-1), being about 700 times that (0.001 min(-1)) on N-free RGO. In mixtures of various phenols, the degradation rate constant of each phenol was linearly increased with its adsorption capacity. A simultaneous use of N-RGO and persulfate yielded fast and efficient removal of bisphenols. The use of N-RGO (120 mg L(-1)) and persulfate (0.6 mmol L(-1)) almost completely removed the added bisphenols (0.385 mmol L(-1)) at pH 6.6 within 17 min. A mechanism study indicated that the adsorption enriched the pollutant, and the catalytically generated sulfate radicals rapidly degrade the adsorbed pollutant, accelerating in turn the adsorption of residual pollutant.
†Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, College of Resources and Environmental Science, South-Central University for Nationalities, Wuhan 430074, P. R. China.|‡College of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China.
Xiaobo
X
Wang
†Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, College of Resources and Environmental Science, South-Central University for Nationalities, Wuhan 430074, P. R. China.
Yanlei
Y
Qin
‡College of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China.
Lihua
L
Zhu
†Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, College of Resources and Environmental Science, South-Central University for Nationalities, Wuhan 430074, P. R. China.
Heqing
H
Tang
D000327:Adsorption; D001559:Benzhydryl Compounds / Q000302:isolation & purification*; D002384:Catalysis; D006108:Graphite / Q000737:chemistry*; D007700:Kinetics; D009584:Nitrogen / Q000737:chemistry*; D010084:Oxidation-Reduction; D010636:Phenols / Q000302:isolation & purification*; D056951:Photoelectron Spectroscopy; D013696:Temperature; D000098826:Bisphenol A Compounds
D001559:Benzhydryl Compounds; D006108:Graphite; D009584:Nitrogen; D010636:Phenols; C006780:bisphenol A; D000098826:Bisphenol A Compounds