Tags

Type your tag names separated by a space and hit enter

Differential control of anode/cathode potentials of paired electrolysis for simultaneous removal of chemical oxygen demand and total nitrogen.

Abstract

Paired electrolysis can take advantage of both anodic oxidation and cathodic reduction, and thus improve current efficiency for electrochemical wastewater treatment. In this work, differential control of anode/cathode potentials of paired electrolysis for simultaneous removal of chemical oxygen demand (COD) and total nitrogen (TN, including ammonia, nitrate, and nitrite) was studied. We first determined the optimal potentials for anodic oxidation of COD/NH4+ or cathodic reduction of NO3-/NO2- (minimization of over-oxidation or over-reduction) by preliminary cyclic voltammetry and constant-potential electrolysis experiments, i.e., 1.6 V for anodic oxidation and -1.26 V for cathodic reduction in this case. The optimal working potential of the cathode was achieved at appropriate current density in the paired electrolysis system, the working potential of the anode was independently controlled by adjusting the ratio of its surface area to that of the cathode. In this way, both the cathode and anode could work under optimal potentials. At an optimized cathodic current density of 5.0 mA cm-2 and cathode/anode surface area ratio of 2:1, the removal efficiencies of COD and TN from simulated wastewater reached 91.9% and 86.2%, respectively. Additionally, the developed paired electrolysis system was validated by treating an actual pharmaceutical wastewater, results for which showed that a total current efficiency of 84.8% was achieved, which was at least twice as high as that of traditional electrochemical processes.

Links

  • Publisher Full Text
  • Authors+Show Affiliations

    ,

    College of Environment, Zhejiang University of Technology, 310014 Hangzhou, China.

    ,

    College of Environment, Zhejiang University of Technology, 310014 Hangzhou, China.

    ,

    College of Environment, Zhejiang University of Technology, 310014 Hangzhou, China.

    ,

    College of Environment, Zhejiang University of Technology, 310014 Hangzhou, China.

    College of Environment, Zhejiang University of Technology, 310014 Hangzhou, China. Electronic address: jdwang@zjut.edu.cn.

    Source

    The Science of the total environment 687: 2019 Jun 08 pg 198-205

    Pub Type(s)

    Journal Article

    Language

    eng

    PubMed ID

    31207510

    Citation

    Yao, Jiachao, et al. "Differential Control of Anode/cathode Potentials of Paired Electrolysis for Simultaneous Removal of Chemical Oxygen Demand and Total Nitrogen." The Science of the Total Environment, vol. 687, 2019, pp. 198-205.
    Yao J, Pan B, Shen R, et al. Differential control of anode/cathode potentials of paired electrolysis for simultaneous removal of chemical oxygen demand and total nitrogen. Sci Total Environ. 2019;687:198-205.
    Yao, J., Pan, B., Shen, R., Yuan, T., & Wang, J. (2019). Differential control of anode/cathode potentials of paired electrolysis for simultaneous removal of chemical oxygen demand and total nitrogen. The Science of the Total Environment, 687, pp. 198-205. doi:10.1016/j.scitotenv.2019.06.106.
    Yao J, et al. Differential Control of Anode/cathode Potentials of Paired Electrolysis for Simultaneous Removal of Chemical Oxygen Demand and Total Nitrogen. Sci Total Environ. 2019 Jun 8;687:198-205. PubMed PMID: 31207510.
    * Article titles in AMA citation format should be in sentence-case
    TY - JOUR T1 - Differential control of anode/cathode potentials of paired electrolysis for simultaneous removal of chemical oxygen demand and total nitrogen. AU - Yao,Jiachao, AU - Pan,Bingjun, AU - Shen,Ruxue, AU - Yuan,Tongbin, AU - Wang,Jiade, Y1 - 2019/06/08/ PY - 2019/04/02/received PY - 2019/05/21/revised PY - 2019/06/06/accepted PY - 2019/6/18/pubmed PY - 2019/6/18/medline PY - 2019/6/18/entrez KW - Chemical oxygen demand KW - Differential control KW - Paired electrolysis KW - Total nitrogen KW - Working potential SP - 198 EP - 205 JF - The Science of the total environment JO - Sci. Total Environ. VL - 687 N2 - Paired electrolysis can take advantage of both anodic oxidation and cathodic reduction, and thus improve current efficiency for electrochemical wastewater treatment. In this work, differential control of anode/cathode potentials of paired electrolysis for simultaneous removal of chemical oxygen demand (COD) and total nitrogen (TN, including ammonia, nitrate, and nitrite) was studied. We first determined the optimal potentials for anodic oxidation of COD/NH4+ or cathodic reduction of NO3-/NO2- (minimization of over-oxidation or over-reduction) by preliminary cyclic voltammetry and constant-potential electrolysis experiments, i.e., 1.6 V for anodic oxidation and -1.26 V for cathodic reduction in this case. The optimal working potential of the cathode was achieved at appropriate current density in the paired electrolysis system, the working potential of the anode was independently controlled by adjusting the ratio of its surface area to that of the cathode. In this way, both the cathode and anode could work under optimal potentials. At an optimized cathodic current density of 5.0 mA cm-2 and cathode/anode surface area ratio of 2:1, the removal efficiencies of COD and TN from simulated wastewater reached 91.9% and 86.2%, respectively. Additionally, the developed paired electrolysis system was validated by treating an actual pharmaceutical wastewater, results for which showed that a total current efficiency of 84.8% was achieved, which was at least twice as high as that of traditional electrochemical processes. SN - 1879-1026 UR - https://www.unboundmedicine.com/medline/citation/31207510/Differential_control_of_anode/cathode_potentials_of_paired_electrolysis_for_simultaneous_removal_of_chemical_oxygen_demand_and_total_nitrogen L2 - https://linkinghub.elsevier.com/retrieve/pii/S0048-9697(19)32674-9 DB - PRIME DP - Unbound Medicine ER -