Environmental Engineering Reference
In-Depth Information
(7) Explain how the photo-ferrioxalate/H
2
O
2
reaction system degrades the
organic pollutants in the aqueous solution.
(8) Explain how photocatalytic TiO
2
suspensions degrade the organic pollutants
in aqueous solutions.
(9) What are the controlling factors for the production and decay of HO
•
?
•
.
(10) Explain the effect of wavelength spectrum, temperature, and pH on the for-
mation of HO
Explain how fulvic acid plays a dual role in production and decay of HO
•
from nitrite and nitrate photolysis in aqueous solution.
(11) Explain the effect of wavelength spectrum and temperature on H
2
O
2
pho-
tolysis in aqueous solution.
(12) Explain how the Fenton reaction is affected by pH, temperature and salinity
in natural waters.
(13) Explain what the photo-Fenton reaction is and what is its kinetics.
(14) What is the photo-ferrioxalate/H
2
O
2
reaction? How is this reaction system
affected by variations in pH and reactants in aqueous solution?
(15) The quantum yield (
Φ
HO
) for the UV photoproduction of HO
•
by nitrite
photolysis at 308 nm is 0.07 at room temperature (298 K). Calculate
Φ
HO
at
the temperatures of 288 and 328 K.
(16) The
Φ
HO
for the UV photoproduction of HO
•
by nitrate photolysis at
308 nm is 0.017 at room temperature (298 K). Calculate the
Φ
HO
at the tem-
peratures of 278 and 318 K.
(17) If the photolysis of aqueous H
2
O
2
at 308 nm generates HO
•
with
Φ
HO
=
1 at
room temperature (298 K), then calculate
Φ
HO
at 288 and 303 K.
(18) Explain shortly the significance of HO
•
formation in natural waters.
•
(19) Explain how HO
impacts on biota in natural waters.
Acknowledgments
This work was financially supported jointly by the National Natural
Science Foundation of China and the Chinese Academy of Sciences. This work was partly
supported by Hiroshima University, Japan; PNRA—Progetto Antartide, University of Turin,
Italy; Brook Byers Institute for Sustainable Systems at Georgia Institute of Technology, the
United States; Aligarh Muslim University, India; and Northwest Missouri State University,
USA. This chapter acknowledges the reprinted from reprinted (adapted) with permission
from Kwan WP, Voelker BM, Decomposition of hydrogen peroxide and organic compounds
in the presence of dissolved iron and ferrihydrite, Environmental Science & Technology,
36 (7), 1467-1476. Copyright (2002) Americal Chemical Society; reprinted (adapted) with
permission from Farias J, Rossetti GH, Albizzati ED, Alfano OM, Solar degradation of formic
acid: temperature effects on the photo-Fenton reaction. Industrial & Engineering Chemistry
Research, 46(23):7580-7586). Copyright (2007) American Chemical Society; reprinted from
Journal of Photochemistry and Photobiology A: Chemistry, 128(1-3), Mack J, Bolton JR,
Photochemistry of nitrite and nitrate in aqueous solution: a review, 1-13. Copyright (1999),
with permission from Elsevier; reprinted from Geochimica et Cosmochimica Acta, 53(8),
Millero FJ, Sotolongo S, The oxidation of Fe(II) with H
2
O
2
in seawater, 1867-1873. Copyright
(1989), with permission from Elsevier; reprinted (adapted) with permission from Southworth
BA, Voelker BM, Hydroxyl radical production via the photo-Fenton reaction in the presence
of fulvic acid, Environmental Science & Technology, 37(6), 1130-1136. Copyright (2003)
American Chemical Society; reprinted with permission from Zepp RG, Faust BC, Hoigné J,
Hydroxyl radical formation in aqueous reactions (pH 3-8) of iron(II) with hydrogen peroxide:
The Photo-Fenton reaction, Environmental Science & Technology, 26 (2), 313-319. Copyright
