Dechlorination of Polychlorinated Biphenyls in Industrial Transformer Oil by Radiolytic and Photolytic Methods
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- 作者：Cynthia G. Jones ; Joseph Silverman ; Mohamad Al-Sheikhly ; Pedatsur Neta ; and Dianne L. Poster
- 刊名：Environmental Science & Technology
- 出版年：2003
- 出版时间：December 15, 2003
- 年：2003
- 卷：37
- 期：24
- 页码：5773 - 5777
- 全文大小：90K
- 年卷期：v.37,no.24(December 15, 2003)
- ISSN：1520-5851
文摘
Used electrical transformer oils containing low or highconcentrations of polychlorinated biphenyls (PCBs) weretreated using electron, 
, and ultraviolet radiation, and theconditions for complete dechlorination were developed.Dechlorination was determined by analysis of the inorganicchloride formed and the concentrations of remainingPCBs.Transformer oil containing 
95 
g g-1 PCB (3.5mmol L-1 Cl) is completely dechlorinated by irradiation with600 kGy after the addition of 10% triethylamine (TEA).Transformer oil containing >800 000 g g-1 PCB (17.7 molL-1 Cl) requires an additional solvent to prevent solidification.When this oil is diluted with 2-propanol (2-PrOH) and TEA(v/v/v, 1/79/20), complete dechlorination is achieved witha dose of 2500 kGy. Ultraviolet photolysis of the sameoil/2-PrOH/TEA solutions led to 90% dechlorination afterexposure for 120 h in our experimental setup. Such yieldswere obtained by radiolysis with a dose of 2000 kGy(300 h in our Gammacell). Replacing TEA with KOH in 2-PrOHsolutions greatly increases the yield of dechlorination inboth the radiolytic and the photolytic experiments,demonstrating that a chain reaction plays a role in bothof these treatment methods and suggesting that both methodsdeserve further consideration for large-scale application.
, and ultraviolet radiation, and theconditions for complete dechlorination were developed.Dechlorination was determined by analysis of the inorganicchloride formed and the concentrations of remainingPCBs.Transformer oil containing 95 g g-1 PCB (3.5mmol L-1 Cl) is completely dechlorinated by irradiation with600 kGy after the addition of 10% triethylamine (TEA).Transformer oil containing >800 000 g g-1 PCB (17.7 molL-1 Cl) requires an additional solvent to prevent solidification.When this oil is diluted with 2-propanol (2-PrOH) and TEA(v/v/v, 1/79/20), complete dechlorination is achieved witha dose of 2500 kGy. Ultraviolet photolysis of the sameoil/2-PrOH/TEA solutions led to 90% dechlorination afterexposure for 120 h in our experimental setup. Such yieldswere obtained by radiolysis with a dose of 2000 kGy(300 h in our Gammacell). Replacing TEA with KOH in 2-PrOHsolutions greatly increases the yield of dechlorination inboth the radiolytic and the photolytic experiments,demonstrating that a chain reaction plays a role in bothof these treatment methods and suggesting that both methodsdeserve further consideration for large-scale application.