Degradación Componentes Organicos

Electrochemical processes for the remediation of wastewater and contaminated
soil: emerging technology
P Chandra Mouli, S Venkata Mohanb and S Jayarama Reddy*
Electrochemical Research Laboratories, Department of Chemistry, Sri Venkateswara University, Tirupati 517 502
The review aims at providing an overview of electrochemical processes used for accomplishing the remediation of
industrialwastewater, particularly elecrooxidation processes and electrocoagulation. The applicability of these technologies
for the remediation of contaminated soil is also discussed. The use of electrochemical process as a pre-treatment step to
enhance the biodegradability of wastewater containing recalcitrant or inhibitory compounds can potentially be justified due to
the formation of intermediate,which is easily degraded in subsequent biological treatment. The enhanced degradation of
wastewater may be attributed to the electrochemical oxidation of the organic compounds present in the aqueous phase to
simple molecules, which may be easily biodegraded. The principle of electrooxidation process, involved in the remediation
process was described along with specific applications. The applicationof electrocoagulation process for wastewater
treatment is also reviewed.
Keywords:

Electrochemical processes,
Contaminated soils.

Electrooxidation,

Introduction
The ecosphere continues to be challenged by the
increasing amount and variability of toxic
contaminants that are emitted by industrial activities
like manufacture of chemicals, including many
pesticides, herbicides,chemicals and pharmaceuticals,
dye stuff units, and meat packing units1-8; which are
more saline9-11. Such environmental contaminants are
becoming more wide spread as the pace of industrial
activity accelerates, especially in the developing
countries, and also as a consequence of the difficulties
in restricting the emissions of industrial activity.
Particularly, rivers, canals, estuaries, andother water
bodies are being constantly polluted due to
indiscriminate discharge of industrial effluents12-14.
Water has acquired increasing importance due to its
two unique characteristics: high specific heat capacity
and high solvent power with respect to many
inorganic and some organic substances. As a
consequence of these two factors; water can serve as a
heat reservoir, cooling agent,steam sources, etc., and
__________
*Author for correspondence
Tel: +91-877-2249962/2248418, Fax: +91-877- 2248592/2248499,
E-mail: profjreddy_s@yahoo.co.in
b
Biochemical and Environmental Engineering Centre,
Indian Institute of Chemical Technology, Hyderabad 500 007

Biodegradability,

Electrocoagulation,

Wastewater,

is subsequently returned to the environment at a hightemperature. On the other hand, water in its function
as a reaction medium, or even a reaction partner, has
now developed into the most significant source of
wastewater in any industry, in particular, chemical
and pharmaceutical processes15. Improper disposal of
these aqueous wastes may increase the probability of
contamination of water resources and is main health
and environmental concern due toits high toxicity.
There is, therefore, an urgent need to develop
innovative, more effective, and inexpensive
technologies for treatment of wastewater. In this
review, we wish to address an overview of
electrochemical
processes
such
as:
(i)
Electrooxidation processes and (ii) Electrocoagulation
to accomplish treatment of industrial wastewater.
Industrial Wastewater Treatment
Treatmentplants intended for the purification of
any industrial wastewater utilize a combination of
processing techniques such as:
— Intended for the elimination of
undissolved
substances,
including
screening,
clarification, and filtration.
Physical Treatment

— Intended to treat
dissolved and suspended pollutants by means of
Physico-chemical/Chemical Treatment

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J SCI IND RES VOL 63...