Sonochemical degradation of 2,3,7,8-tetrachlorodibenzo-p-dioxins in aqueous solution with Fe(III)/UV system.
2,3,7,8-Tetrachlorodibenzo-p-dioxin (2,3,7,8-TeCDD) was rapidly decreased by sonication in aqueous solution. The degradation efficiency was strongly influenced by ultrasonic power and reaction temperature. An initial 2,3,7,8-TeCDD concentration of 20 ng l(-1) was completely degraded within 60 min under sonochemical conditions using a 20 kHz frequency with a 150 W ultrasound power. The activation energy is 21.9 kJ/mol in the temperature range of 10-40 degrees C, suggesting a diffusion-controlled reaction. To increase the efficiency of 2,3,7,8-TeCDD treatment, degradation system combined ultrasound with Fe(III) (2 x 10(-4)mol l(-1)) and UV irradiation. Both UV and Fe(III) induced Fenton, Fenton-like and photo-Fenton reactions, leading to additional OH radicals and rapid 2,3,7,8-TeCDD removal.
Katsumata
Hideyuki
H
Department of Chemistry for Materials, Graduate School of Engineering, Mie University, Tsu, Mie 514-8507, Japan. hidek@chem.mie-u.ac.jp <hidek@chem.mie-u.ac.jp>
Kaneco
Satoshi
S
Suzuki
Tohru
T
Ohta
Kiyohisa
K
Yobiko
Yoshihiro
Y
D004147:Dioxins / Q000737:chemistry*; D004785:Environmental Pollutants / Q000737:chemistry*; D052918:Environmental Restoration and Remediation; D006861:Hydrogen Peroxide / Q000737:chemistry; D007501:Iron / Q000737:chemistry*; D012996:Solutions; D013010:Sonication; D013696:Temperature; D014466:Ultraviolet Rays
C092566:2,3,7,8-tetrafluorodibenzodioxin; D004147:Dioxins; D004785:Environmental Pollutants; C045076:Fenton's reagent; D012996:Solutions; D006861:Hydrogen Peroxide; D007501:Iron