A new strategy for determination of current efficiency during electro-oxidation of aromatic compounds in a packed-bed system

2011 ◽  
Vol 63 (11) ◽  
pp. 2685-2691 ◽  
Author(s):  
Lizhang Wang ◽  
Yuemin Zhao ◽  
Qingyu Gao ◽  
Cheng Qian ◽  
Yunlong Hu
Keyword(s):  
Current Efficiency ◽  
Aromatic Compounds ◽  
Oxygen Demand ◽  
Packed Bed ◽  
Electrode System ◽  
Electrode Distance ◽  
Faradaic Current ◽  
Packed Bed Electrode ◽  
New Strategy ◽  
Electro Oxidation

The electro-oxidation of aromatic compounds in 4,4′-diaminostilbene-2,2′-disulfonic (DSD) acid wastewater on IrO2–Ta2O5/Ti anodes was studied. The current efficiency was evaluated in terms of chemical oxygen demand (COD) by introducing a new factor, the fraction of the Faradaic current to the total cell current (β) through the network analysis of packed bed electrode system (PBEs). Experimental results using an up-flow PBEs at current intensities ranging from 5 to 16 A m−2, flow rates ranging from 20 to 80 L h−1 and inter-electrode distance of 5 to 50 cm are in good agreement with the proposed equation. In addition, lower current density, increasing flow rate and larger inter-electrode distance are beneficial to enhance the current efficiency.

Modeling approach to phenol oxidation by a sand-based packed-bed electrode system (SPBEs)

2012 ◽  
Vol 66 (2) ◽  
pp. 422-428 ◽  
Author(s):  
Lizhang Wang ◽  
Peng Li ◽  
Qian Yan
Keyword(s):  
Mass Transport ◽  
Current Density ◽  
Oxygen Demand ◽  
Cell Voltage ◽  
Packed Bed ◽  
Theoretical Description ◽  
Electrode System ◽  
Phenol Oxidation ◽  
Packed Bed Electrode ◽  
Initial Ph

A comparative study of phenol oxidation using pure electrolysis (PEs) and sand-based packed-bed electrode systems (SPBEs) was performed under conditions of phenol concentration 800 mg L−1, initial pH 6.5, current density 100 A m−2 and sodium sulfate (Na2SO4) 3.0% (w/w) on IrO2–Ta2O5/Ti anode. The results show quartz sand, a non-conducting material is incapable of expanding the electrode area and the phenol oxidation in SPBEs commences only at the electrode surface. From the theoretical description of the mass transport coefficient and chemical oxygen demand (COD), we confirm that the enhancement of the COD removal efficiency, current and space–time yields in SPBEs is due to the improvement of mass transport properties. The proposed SPBEs shows superiority to the PEs on saving energy at the same applied voltage, however, when operated under the same applied current density the energy consumption of the former would be much higher than that of the latter because of the rise of the applied cell voltage.

Electro-oxidation rate ofp-tert-butyltoluene in a bipolar packed-bed electrode cell

1987 ◽  
Vol 17 (6) ◽  
pp. 1213-1222 ◽  
Author(s):  
Hark Joon Kim ◽  
Katsuki Kusakabe ◽  
Satoko Hokazono ◽  
Shigeharu Morooka ◽  
Yasuo Kato
Keyword(s):  
Oxidation Rate ◽  
Packed Bed ◽  
Packed Bed Electrode ◽  
Electrode Cell ◽  
Electro Oxidation

scholarly journals A 2.5D Electrode System Constructed of Magnetic Sb–SnO2 Particles and a PbO2 Electrode and Its Electrocatalysis Application on Acid Red G Degradation

Catalysts ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 875 ◽  
Author(s):  
Yuan ◽  
Salman ◽  
Guo ◽  
Xu ◽  
Xu ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Current Efficiency ◽  
Electrochemical Oxidation ◽  
High Performance ◽  
Oxygen Demand ◽  
Electrode System ◽  
Toc Removal ◽  
Pbo2 Electrode ◽  
Higher Temperature ◽  
Acid Red G

A novel electrode consisting of a Ti/PbO2 shell and Fe3O4/Sb–SnO2 particles was developed for electrochemical oxidation treatment of wastewater. Scanning electron microscope (SEM), X-ray diffraction (XRD), the current limiting method, toxicity experiments, and high-performance liquid chromatography were adopted to characterize its morphology, crystal structure, electrochemical properties, the toxicity of the wastewater, and hydroxyl radicals. Acid Red G (ARG), a typical azo dye, was additionally used to test the oxidation ability of the electrode. Results indicated that the 2.5D electrode could significantly improve the mass transfer coefficient and •OH content of the 2D electrode, thereby enhancing the decolorization, degradation, and mineralization effect of ARG, and reducing the toxicity of the wastewater. The experiments revealed that, at higher current density, lower dye concentration and higher temperature, the electrochemical oxidation of ARG favored. Under the condition of 50 mA/cm2, 25 °C, and 100 ppm, the ARG, Chemical Oxygen Demand (COD) and Total Organic Carbon (TOC) removal efficiency reached 100%, 65.89%, and 52.52%, respectively, and the energy consumption and the current efficiency were 1.06 kWh/g COD, 8.29%, and energy consumption for TOC and mineralization current efficiency were 3.81 kWh/g COD, 9.01%. Besides, the Fe3O4/Sb–SnO2 particles after electrolysis for 50 h still had remarkable stability. These results indicated that the ARG solution could be adequately removed on the 2.5D electrode, providing an effective method for wastewater treatment.

Kinetics for electro-oxidation of organic pollutants by using a packed-bed electrode reactor (PBER)

2016 ◽  
Vol 284 ◽  
pp. 240-246 ◽  
Author(s):  
Lizhang Wang ◽  
Bo Wu ◽  
Peng Li ◽  
Bo Zhang ◽  
N. Balasubramanian ◽  
...  
Keyword(s):  
Organic Pollutants ◽  
Packed Bed ◽  
Packed Bed Electrode ◽  
Electro Oxidation

Electrochemical capacitance behavior of a packed bed electrochemical reactor toward phenol electro-oxidation

2014 ◽  
Vol 45 (2) ◽  
pp. 177-184 ◽  
Author(s):  
Peng Li ◽  
Yuemin Zhao ◽  
Lizhang Wang ◽  
Binbin Ding ◽  
Bo Zhang ◽  
...  
Keyword(s):  
Packed Bed ◽  
Electrochemical Reactor ◽  
Electrochemical Capacitance ◽  
Electro Oxidation

Degradation of wine distillery wastewaters by the combination of aerobic biological treatment with chemical oxidation by Fenton's reagent

2005 ◽  
Vol 51 (1) ◽  
pp. 167-174 ◽  
Author(s):  
J. Beltran de Heredia ◽  
J. Torregrosa ◽  
J.R. Dominguez ◽  
E. Partido
Keyword(s):  
Chemical Oxygen Demand ◽  
Aromatic Compounds ◽  
Biological Treatment ◽  
Batch Reactor ◽  
Oxygen Demand ◽  
Chemical Oxidation ◽  
Utilization Rate ◽  
Fenton’S Reagent ◽  
Kinetic Rate Constant ◽  
Fenton's Reagent

The degradation of wine distillery wastewaters by aerobic biological treatment has been investigated in a batch reactor. The evolution of the chemical oxygen demand, biomass and total contents of polyphenolic and aromatic compounds was followed through each experiment. According to the Contois model, a kinetic expression for the substrate utilization rate is derived, and its biokinetic constant is evaluated. The final effluents of the aerobic biological experiments were oxidized by Fenton's reagent. The evolution of chemical oxygen demand, hydrogen peroxide concentration and total contents of polyphenolic and aromatic compounds was followed through each experiment. A kinetic model to interpret the experimental data is proposed. The kinetic rate constant of the global reaction is determined.

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