title: Investigation of the synergistic effects for p-nitrophenol mineralization by a combined process of ozonation and electrolysis using a boron-doped diamond anode.
abstract: Electrolysis and ozonation are two commonly used technologies for treating wastewaters contaminated with nitrophenol pollutants. However, they are often handicapped by their slow kinetics and low yields of total organic carbon (TOC) mineralization. To improve TOC mineralization efficiency, we combined electrolysis using a boron-doped diamond (BDD) anode with ozonation (electrolysis-O3) to treat a p-nitrophenol (PNP) aqueous solution. Up to 91% TOC was removed after 60 min of the electrolysis-O3 process. In comparison, only 20 and 44% TOC was respectively removed by individual electrolysis and ozonation treatment conducted under similar reaction conditions. The result indicates that when electrolysis and ozonation are applied simultaneously, they have a significant synergy for PNP mineralization. This synergy can be mainly attributed to (i) the rapid degradation of PNP to carboxylic acids (e.g., oxalic acid and acetic acid) by O3, which would otherwise take a much longer time by electrolysis alone, and (ii) the effective mineralization of the ozone-refractory carboxylic acids to CO2 by OH generated from multiple sources in the electrolysis-O3 system. The result suggests that combining electrolysis with ozonation can provide a simple and effective way to mutually compensate the limitations of the two processes for degradation of phenolic pollutants.
authors.affiliation: School of Environment, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing 100084, China.
authors.forename: Cuicui
authors.initials: C
authors.lastname: Qiu
authors.affiliation: School of Environment, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing 100084, China; Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China.
authors.forename: Shi
authors.initials: S
authors.lastname: Yuan
authors.affiliation: School of Environment, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing 100084, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Li
authors.affiliation: School of Environment, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing 100084, China.
authors.forename: Huijiao
authors.initials: H
authors.lastname: Wang
authors.affiliation: School of Environment, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing 100084, China.
authors.forename: Belal
authors.initials: B
authors.lastname: Bakheet
authors.affiliation: Department of Ecosystem Science and Management and Material Research Institute, 205 MRL Building, The Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: Sridhar
authors.initials: S
authors.lastname: Komarneni
authors.affiliation: School of Environment, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing 100084, China; Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China. Electronic address: wangyujue@tsinghua.edu.cn.
authors.forename: Yujue
authors.initials: Y
authors.lastname: Wang
mesh_terms: D001895:Boron; D018130:Diamond; D004566:Electrodes; D004572:Electrolysis; D009596:Nitrophenols / Q000737:chemistry*; D010126:Ozone / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
chemical_list: D009596:Nitrophenols; D014874:Water Pollutants, Chemical; D010126:Ozone; D018130:Diamond; D001895:Boron; C024836:4-nitrophenol
keywords: Advanced oxidation; Boron-doped diamond; Ozone; Phenol; Wastewater