20    ADVANCED CHEMICAL OXIDATION AND
TOXICITY REDUCTION OF
2,4,6 -TRICHLOROPHENOL BY USING FENTON'S
REAGENT - PART III: A COMPARISON WITH
UV - PEROXIDE TREATMENT
Somnath Basu, Program Manager
Deer Island Treatment Plant
Massachusetts Water Resources Authority
Winthrop, Massachusetts 02152
Venkat Sreenivasan, Master's Student
Department of Civil & Environmental Engineering
Northeastern University
Boston, Massachusetts 02115
Irvine W. Wei, Associate Professor
Department of Civil & Environmental Engineering
Northeastern University
Boston, Massachusetts 02115
INTRODUCTION
Removal of hazardous organic chemicals dissolved in groundwater or industrial wastewater
poses a major environmental problem. Commonly used physical separation techniques; e.g., air
stripping, carbon adsorption, etc., are not permanent solutions because they are only phase transformative. Eventually, the gaseous or solid phases into which the organic molecules concentrate
have to be properly cleaned up and disposed of.
Biological oxidation of organic compounds has been the traditional technique of wastewater
treatment. But many substances, in industrial wastewaters particularly, resist biodegradation and
may even be biocides. Moreover, in groundwater, there may be organics in concentrations so low
that they may not be able to sustain biological growth.
The liquid phase chemical oxidative treatment is one of the most common techniques for destruction of organic pollutants in water. Chlorine, ozone, hydrogen peroxide, etc., are among the
commonly used chemical oxidants. Chlorine, in various oxidation states, is extensively used in
municipal water and wastewater treatment. It has these major disadvantages—handling of chlorine in treatment plants is hazardous, and chlorine also may form various chlorinated organic byproducts, including THMs, that are themselves hazardous organic chemicals.
Lately, advanced oxidation processes (AOP) involving treatment by ozone, UV-hydrogen peroxide, and metal ion catalyzed peroxide, have received widespread attention from the scientific
and engineering community because they break down complex organic compounds into simpler
oxidized molecules, amenable to biotreatment by conventional wastewater treatment processes.
In many cases, a good part of the breakdown reactions proceed all the way to complete oxidation. They all generate highly energized hydroxyl radicals, which act as the oxidant of the complex organic compounds.
UV-peroxide treatment was effectively utilized on a laboratory scale to degrade several chlorinated aliphatic hydrocarbons, including DCE, TCE, TCA, PCE, etc.,1 and also aromatic hydrocarbons, including chlorinated phenols. The reaction kinetics of individual pure compounds
were studied, and also an attempt was made to identify the reaction products. A successful pilot-
51st Purdue Industrial Waste Conference Proceedings. 1996, Ann Arbor Press. Inc., Chelsea, Michigan 48118.
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