TY - JOUR
T1 - Tubular carbon nanotube-based gas diffusion electrode removes persistent organic pollutants by a cyclic adsorption - Electro-Fenton process
AU - Roth, Hannah
AU - Gendel, Youri
AU - Buzatu, Pompilia
AU - David, Oana
AU - Wessling, Matthias
N1 - Publisher Copyright:
© 2016 Elsevier B.V.
PY - 2016/4/15
Y1 - 2016/4/15
N2 - We report a novel tubular electrochemical cell which is operated in a cyclic adsorption - electro-Fenton process and by this means overcomes the drawbacks of the traditional electro-Fenton process. A microtube made only of multi-walled carbon nanotubes (MWCNT) functions as a gas diffusion electrode (GDE) and highly porous adsorber. In the process, the pollutants were first removed electroless from the wastewater by adsorption on the MWCNT-GDE. Subsequently, the pollutants are electrochemically degraded in a defined volume of electrolyte solution using the electro-Fenton process. Oxygen was supplied into the lumen of the saturated microtubular GDE which was surrounded by a cylindrical anode made of Ti-felt coated with Pt/IrO2 catalysts. For the proof of concept the model pollutant Acid Red 14 (AR14), an azo dye, was used. The decomposition of AR14 was studied at different applied current densities and initial concentrations of ferrous iron in the electrolyte solution. At optimal conditions, complete regeneration of the adsorption capacity of the MWCNT-GDE, complete decolorization and TOC and COD removal rates of 50% and 70% were achieved, respectively. The MWCNT-GDE is regenerated and again available for adsorption. This approach allows water treatment independent of its composition, thus does not require any addition of chemicals to the wastewater.
AB - We report a novel tubular electrochemical cell which is operated in a cyclic adsorption - electro-Fenton process and by this means overcomes the drawbacks of the traditional electro-Fenton process. A microtube made only of multi-walled carbon nanotubes (MWCNT) functions as a gas diffusion electrode (GDE) and highly porous adsorber. In the process, the pollutants were first removed electroless from the wastewater by adsorption on the MWCNT-GDE. Subsequently, the pollutants are electrochemically degraded in a defined volume of electrolyte solution using the electro-Fenton process. Oxygen was supplied into the lumen of the saturated microtubular GDE which was surrounded by a cylindrical anode made of Ti-felt coated with Pt/IrO2 catalysts. For the proof of concept the model pollutant Acid Red 14 (AR14), an azo dye, was used. The decomposition of AR14 was studied at different applied current densities and initial concentrations of ferrous iron in the electrolyte solution. At optimal conditions, complete regeneration of the adsorption capacity of the MWCNT-GDE, complete decolorization and TOC and COD removal rates of 50% and 70% were achieved, respectively. The MWCNT-GDE is regenerated and again available for adsorption. This approach allows water treatment independent of its composition, thus does not require any addition of chemicals to the wastewater.
KW - Adsorption
KW - Carbon nanotubes
KW - Electro-Fenton
KW - Tubular gas diffusion electrode
UR - http://www.scopus.com/inward/record.url?scp=84960337332&partnerID=8YFLogxK
U2 - 10.1016/j.jhazmat.2015.12.066
DO - 10.1016/j.jhazmat.2015.12.066
M3 - Article
AN - SCOPUS:84960337332
SN - 0304-3894
VL - 307
SP - 1
EP - 6
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
ER -