Oxidation and reduction applied to water treatment — Oxygen, chlorine and derivatives

The objectives of the various articles making up this dossier are set out in the introduction to the first article. , which was devoted to the general principles governing redox phenomena and processes in their application to water treatment: overview of fields of use, reminder of definitions and chemical bases, graphic representations (potential-pH and pe-pH diagrams), principles for classifying oxidizers and reducers according to their potency.

This article presents the most traditional oxidizers: oxygen (atmospheric or industrial), chlorine and its derivatives (hypochlorites, chloramines, chlorine dioxide). The third article presents the other oxidants, in particular those involving technologies that are still in constant progress (ozone, "advanced oxidation" processes), as well as the main reducing agents. Practical applications in various water treatments will be the subject of a fourth and final article.