Scale-up in PEM electro-ozonizers for the degradation of organics
At a Glance
Section titled “At a Glance”| Metadata | Details |
|---|---|
| Publication Date | 2021-12-11 |
| Journal | Separation and Purification Technology |
| Authors | M. Rodríguez-Peña, J.A. Barrios, Justo Lobato, Cristina Sáez, Carlos Barrera-Díaz |
| Institutions | University of Castilla-La Mancha, Universidad Autónoma del Estado de México |
| Citations | 15 |
Abstract
Section titled “Abstract”This work focuses on the scale-up of electro-ozonizers by evaluating the production of ozone and the degradation of clopyralid synthetic wastes using three commercial PEM electrolyzers. The mechanical concept of the three cells is similar: a single compartment cell equipped with a MEA (consisting of a polymer exchange membrane and two pressed diamond coatings electrodes), powered with monopolar electric connection and where water flows on the surface of the electrodes, although the main electrolyte is the Nafion proton exchange membrane. However, their size and recommended operating conditions are not as similar, and their comparison becomes a good scaleup case study. The CabECO® cell consists of 2 MEAs with a total surface area of 24 cm2, a maximum operating current density of 2. 0A. The Mikrozom® cell consists of only one MEA with a net surface electrodic area of 112 mm2 and a maximum operation current density of 1.0 A. Finally, the CONDIAPURE® cell consists of a single MEA with a total surface area of 146 cm2 and a maximum operation current density of 10.0 A. The performance under mild and extreme operating conditions was compared and the results show that, although the cell concept is similar, the results obtained differ very significantly. The three PEM electrolyzers tested can produce ozone efficiently and mineralize completely clopyralid. The only intermediates measured come from the cathodic hydrodechlorination of clopyralid and oxidative intermediates were only detected at trace concentrations. CabECO® cell demonstrates an outstanding performance with very high current efficiencies in the production of ozone. However, the highest mineralization efficiencies are obtained with the Microzon®, which, although it is the PEM electrolyzer with the smallest active area, is the most efficient because can reach high ozone concentrations and achieve the best clopyralid mineralization. Efficiencies as high as 0.47 mg O3 Wh−1 can be obtained with this cell. Slightly lower values are reached by the CabECO® cell (0.38 mg O3 Wh−1). Enlarging electrode surface area does not seem to be a good strategy from the viewpoint of efficiency and it seems to promote side reactions that compete with ozone production and with the degradation of organics. This means that stacking rather than electrode enlarging should be the strategy more advisable for scaling up the electro-ozonation technology.
Tech Support
Section titled “Tech Support”Original Source
Section titled “Original Source”References
Section titled “References”- 2019 - Environmental applications of electrochemical technology. What is needed to enable full-scale applications? [Crossref]
- 2021 - Critical review of advanced oxidation processes in organic wastewater treatment [Crossref]
- 2018 - Electrochemical oxidation of organic pollutants for wastewater treatment [Crossref]
- 2019 - Recent progress in the applications of boron doped diamond electrodes in electroanalysis of organic compounds and biomolecules - A review [Crossref]
- 2018 - Boron doped diamond: A designer electrode material for the twenty-first century [Crossref]
- 2021 - Developments in electrode materials for wastewater treatment [Crossref]
- 2021 - Recent advances on the use of active anodes in environmental electrochemistry [Crossref]
- 2021 - A novel single-stage ceramic membrane moving bed biofilm reactor coupled with reverse osmosis for reclamation of municipal wastewater to NEWater-like product water [Crossref]
- 2021 - CNTs/MOF-808 painted plates for extended treatment of pharmaceutical and agrochemical wastewaters in a novel photocatalytic reactor [Crossref]
- 2020 - Computational fluid dynamics and factor analysis of a novel swirling demulsified airlift loop reactor for the treatment of refined soybean oil wastewater [Crossref]