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196 Industrial Wastewater Treatment, Recycling, and Reuse
its character, as well as temperature, have a substantial influence on final effi-
ciency. The Fenton reagent destroys a wide variety of organic compounds
without the formation of toxic by-products. Among the different technol-
ogies reported in the literature for the treatment of highly contaminated
effluents, Fenton’s reagent is characterized by its cost effectiveness, simplic-
ity, and suitability for treating aqueous wastes showing variable composi-
tions. This method offers a cost-effective source of highly oxidizing
species, using easy-to-handle reagents. The important advantage of the
Fenton process is that oxidation and coagulation take place simultaneously
(Barbusi nski, 2009).
The electrochemical oxidation process has been known for many years as
a potential technology for water treatment using in situ generated oxidants
such as chlorine and sodium hypochlorite. Commercialization of boron-
doped diamond (BDD) technology has brought a revolutionary change in
the electrochemical oxidation process. It has been proved that BDD, when
used as an anode, is able to generate hydroxyl radicals (as generated in the
Fenton process) without the use of any chemicals. BDD anodes are able
to generate other more stable oxidants such as hydrogen peroxide, perox-
ides, and hypochlorite along with hydroxyl radicals for effective wastewater
treatment.
4.3 FENTON PROCESS: ADVANCED OXIDATION
TECHNOLOGIES
The Fenton process as an advanced oxidation technology has several
advantages:
1. Simple to implement
2. Low capital cost
3. Effective across a broad range of organic compounds
4. Nonselective in oxidation of organics
5. Effective as pretreatment to a biological process.
The Fenton process is the simplest of all the advanced oxidation processes.
It can be executed by mixing readily available oxidants and catalysts (see
Figure 4.1; www.xh2osolutions.com). The reaction can be carried out using
either a batch mode or a continuous mode with simple reactor design. The
capital cost of the Fenton process is relatively low due to the simple nature
of the reactor design involved. Hydroxyl radicals generated from the Fenton
process are the most powerful radicals that unselectively destroy organic
compounds. One of the biggest benefits of Fenton oxidation is that it has