&EPA
United States
Environmental Protection
Agency
EPA/540/F-93/509
August 1993
SUPERFUND INNOVATIVE
TECHNOLOGY EVALUATION
Emerging Technology Bulletin
Removal of Phenol from Aqueous Solutions Using High Energy
Electron Beam Irradiation
Florida International University and the University of Miami
Technology Description
Irradiation of aqueous solutions'with high-energy electrons re-
sults in the formation of the aqueous electron, e'a, hydrogen
radical, H-, and the hydroxyl radical, OH-. These reactive tran-
sient species initiate chemical reactions capable of destroying
organic compounds in aqueous solution, in most cases oxidizing
them to carbon dioxide, water and salt. No sludge is formed and
no pretreatment is necessary. The reaction by-products are non-
toxic and thus this process represents a new technology for the
restoration of contaminated water, soils and sediments.
At one end of the system, an aqueous solution containing the
hazardous organic chemical(s) is directed over a weir where it
falls in a thin sheet (approximately 4 millimeters thick). At the
other end of the system, a 1.5-million volt insulated core trans-
former (1CT) electron accelerator generates electrons and accel-
erates them to approximately 97% the speed of light. These
accelerated electrons are propelled in a concentrated beam down
a high-vacuum tube toward a scanner which scans the beam to a
rectangular shape and directs ft toward the aqueous solution
which is flowing over the weir. It is at this point, when the
electrons penetrate the waste stream, that treatment occurs. The
studies have been conducted at 120 gal/min, and can be easily
scaled up for larger applications. The process is essentially pH
independent in the range 3-11.
Waste Applicability
Current studies using high energy electron beam irradiation have
demonstrated that the process is efficient for the destruction of
several classes of hazardous organic compounds. These studies
have been extended to the destruction of phenol in aqueous
solution in a large-scale flow-through system. Studies were con-
ducted at solute concentrations of 1, 10 and 50 mg L'1, over the
pH range 5-9, in the presence and absence of 3% w/w kaolin
clay.
Test Results
High energy electron beam irradiation effectively removes phenol
from aqueous solutions at large scale. Removal is affected by
solute concentration, absorbed dose and total alkalinity. Other
water quality parameters such as the presence of suspended
solids and solution pH are not important factors influencing com-
pound removal. At high phenol concentration (-950 \iM), recircu-
No Clay
3% Clay
O Influent
• Effluent
100
200 300 400 500
Absorbed Dose (krad)
70
60
50
40
30
20
10
0
600 700
100 200 300 400 500 600
Absorbed Dose (krad)
700
Figure 1. Removal of phenol in the presence and absence of inert solids ( 3% clay) using the electron beam treatment process.
^X> Printed on Recycled Paper
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latton of the waste stream was necessary to destroy all of the
phenol and its reaction by-products.
it was shown that high energy electron beam irradiation leads to
the formation of oxidized reaction by-products. At low doses and
tow phenol concentrations, more than 50% of the decomposition
of phenol was attributed to the formation of hydroquinone, cat-
©chol and trace amounts of resoreinoL The formation of these di-
hydroxy phenol derivatives correspond closely to those reported
as reaction by-products of phenol with OH- radicals. In addition,
aldehydes and formic acid were also identified as reaction by-
products.
For Further Information:
Franklin Alvarez, EPA Project Manager
Risk Reduction Engineering Laboratory
USEPA
26 West Martin Luther King Drive
Cincinnati, OH 45268
(513) 569-7631
Fax (513) 56i-7620
Technology Developer Contact:
William J. Cooper
Drinking Water Research Center
Florida International University
Miami, FL 33199
(305) 348-3049
FAX (305) 348-3894
Charles N. Kurucz
Department of Management Science and Industrial Engineering
University of Miami
Coral Gables, FL 33134
(305) 284-6595
FAX (305) 284-2321
Thomas D. Waite
High Voltage Environmental Applications, Inc.
9562 Doral Boulevard
Miami, FL 33178
(305) 593-5330
(305) 533-0071 (FAX) *U.S. Government Printing Offics: 1993 — 750-071/80058
United States
Environmental Protection Agency
Center for EnvironmentaJ Research Information
Cincinnati, OH 45268
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EPA
PERMIT No. G-35
EPA-S4Q/F-93/509
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