Lee Minju, Oh Jeill
Department of Civil and Environmental Engineering, Chung-Ang University, 221 Heukseok-Dong, Dongjak-Gu, Seoul 156-756, Republic of Korea.
Ultrason Sonochem. 2010 Jan;17(1):207-12. doi: 10.1016/j.ultsonch.2009.06.018. Epub 2009 Jul 3.
Herein, the ultrasonic degradation of trichloroethylene (TCE) and carbon tetrachloride (CT) are reported. The degradation rate for TCE increased by 27% with a decrease in the initial concentration of TCE from 10 to 1 mg L(-1), while the degradation rate of CT was not influenced significantly (<3%) at varying initial concentrations. The addition of t-BuOH, a hydroxyl radical scavenger, decreased the degradation rate of TCE to 22-33%. However, this addition did not affect the degradation rate of CT. Sonolysis of aqueous mixtures of TCE and CT indicated that the degradation rate of TCE was enhanced significantly in the presence of CT, while the degradation rate of CT was slightly inhibited in the presence of TCE. The enhancement of TCE degradation is attributed to both the increase of hydroxyl radical concentration by scavenging of CT for hydrogen atoms and the generation of chlorine-containing radicals such as CCl(3)(), CCl(2)(), Cl(*), and HClO from pyrolysis of CT during sonolysis of CT.
在此，报道了三氯乙烯（TCE）和四氯化碳（CT）的超声降解情况。当TCE的初始浓度从10 mg L⁻¹降至1 mg L⁻¹时，TCE的降解率提高了27%，而在不同初始浓度下，CT的降解率未受到显著影响（<3%）。添加羟基自由基清除剂叔丁醇（t-BuOH）后，TCE的降解率降至22 - 33%。然而，这种添加并未影响CT的降解率。TCE和CT的水混合液的声解表明，在CT存在下，TCE的降解率显著提高，而在TCE存在下，CT的降解率略有抑制。TCE降解的增强归因于CT夺取氢原子导致羟基自由基浓度增加，以及在CT声解过程中CT热解产生含氯自由基，如CCl₃⁎、CCl₂⁎、Cl⁎和HClO。
