BACKGROUND

Fenton Reaction: General Overview

Many transition metals like iron, copper, manganese and cobalt have special oxygen transfer properties which improve the utility of hydrogen peroxide (H₂O₂). The most common of these is iron (Fe) which under appropriate conditions, catalyses the generation of the highly reactive hydroxyl radicals (OH·). The reactivity of this system was first observed by H.J.H Fenton when he reported the oxidation of malic acid in a solution of ferrous ion and hydrogen peroxide. It has been shown that the Fenton’s reagent (iron catalyzed H₂O₂) can oxidize many substrates, including organic matter, and this type of chemistry is known as ‘Fenton Chemistry’.

The Fenton reaction pathway is given as:

Fe²⁺ + H₂O₂ ® Fe³⁺ + OH^- + OH·

Fe²⁺ acts as a catalyst in the above reaction and is regenerated by the following reaction:

Fe³⁺ + H₂O₂ ® Fe²⁺ + HO₂/O₂^- + H⁺

Fe³⁺ + HO₂/O₂^- ® Fe²⁺ + O₂ + H⁺

APPLICATION

Fenton’s reagent is used in the treatment of a variety of industrial wastes, wastewaters, sludges and contaminated soils, containing toxic organic compounds like phenol, formaldehyde, and other complex wastes derived from dyestuffs, pesticides, and rubber chemicals. Treatment involves:

· Organic pollutant destruction

· BOD/COD removal

· Toxicity reduction

· Biodegradability improvement.

In the area of remediation, a number of typical pollutants in both soil and water have been studied. Research is being conducted for adaptation and process optimization of Fenton chemistry for in situ oxidation of organic contaminants in soil and groundwater.

Dr. Voelker’s research aims at understanding the mechanisms of decomposition of hydrogen peroxide and organic contaminants in the presence of iron, and to develop modeling approaches that optimize the efficiency of contaminant oxidation during soil and water remediation.

Reference material acquired from:

Reference Library/Applications:Industria…agent/Iron-Catalyzed Hydrogen Peroxide

http://web.mit.edu/civenv/parsonslab/faculty/voelker.html