Electrochemical generation of chlorine dioxide for use in environmental remediation

Author(s)

da Silva, Leticia Mirella ; Mena, Ismael F. ; Montiel, Miguel A. ; Saez, Cristina ; Motheo, Artur J. ; Rodrigo, Manuel A.

• Document type: Journal article
• Source: PROCESS SAFETY AND ENVIRONMENTAL PROTECTION; v. 177, p. 11-pg., 2023-09-01.

Abstract

This work focuses on the production, in continuous mode, of chlorate and hydrogen peroxide, using tailored electrochemical cells specially designed to obtain high efficiencies in these electrochemical processes. Then, these chlorate and hydrogen peroxide electrochemically produced were mixed for the chemical formation of chlorine dioxide, susceptible to be used for environmental applications. In this work, not only the prototype's conceptualization, design, and 3-D printing manufacturing are realized, but also the characterization of the cells in terms of fluid dynamics, mass transfer, and production of the target compounds is made. The chlorate pro-totype, with an electrode area of 78.5 cm2, produced up to 1200 mg h-1 of a chlorate solution with a purity of 50 %. The hydrogen peroxide prototype, with an electrode surface area of 10.9 cm2, produced up to 9 mg h-1 of hydrogen peroxide with a concentration of up to 70 mg L-1. The chlorine dioxide was produced continuously with these compounds (HClO3 and H2O2), operating at low H2O2/HClO3 ratios and with a highly acidic sup-porting media. The oxidant was effectively transferred to a gaseous stream through air stripping. It was then introduced to solutions containing iodine or methomyl to confirm its ability to oxidize substances and to assess its potential use for environmental applications. These findings indicate that using Gaseous Oxidants Mediated Electrochemical Technology (GOMET) with chlorine dioxide is a viable solution for environmental remediation, offering promising prospects for future research on this topic. (AU)

• FAPESP's process: 21/06908-0 - Electrochemical treatment for the removal of carbamates from contaminated soil
• Grantee: Leticia Mirella da Silva
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• FAPESP's process: 17/10118-0 - Study and application of electrochemical technology for the analysis and degradation of endocrine interferents: materials, sensors, processes and scientific dissemination
• Grantee: Marcos Roberto de Vasconcelos Lanza
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 18/26475-9 - Evaluation and application of electrodes of oxide mixtures and boron doped diamond for the degradation of organic compounds with activity of endocrine interference
• Grantee: Leticia Mirella da Silva
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)