• JOURNAL OF ELECTRICAL WORLD
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• s.365
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• pp.42-45
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• 2007

• 동위원소뉴스
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• no.1 s.121
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• pp.7-9
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• 2007

• Journal of Environmental Science International
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• v.21 no.5
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• pp.573-578
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• 2012

In this study, adsorption of polychlorinated biphenyls(PCBs) in transformer oil on powder activated carbon (PAC) and synthetic zeolite was evaluated. Adsorption characteristics of PCBs on the PAC and zeolite has been investigated in a batch system with respect to adsorbents amount and contact time. BET results showed 908 m2/g for PAC and 483 m2/g for zeolite. The adsorption capacity of PCBs increased with an increasing input amount of absorbent. The adsorption experimental results showed that PAC removed 90% of input PCBs in transformer oil while zeolite removed only 64%. Adsorption of PCBs to PAC and zeolite fit the Freundlich model well. The Freundlich parameter, Kf, for PAC and zeolite was 193.1 and 43.0 respectively, indicating that PAC is effect adsorbent for PCBs adsorption in transformer oil.

• Analytical Science and Technology
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• v.23 no.3
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• pp.247-254
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• 2010

This study was carried out to produce Reference Materials (RMs) for Proficiency Testing (PT) of PCBs in waste analytical laboratories. Two RMs were prepared from used transformer oil samples and PCB free transformer oil by spiking PCBs standard solutions. The spiked PCB RMs were homogenized by mixing and settling up to 90 days. Homogenized concentration of PCBs with Arochlor 1254 (6 ppm), 1254:1260 (1:1) (5 ppm) were observed in 60 days stationary phase but Arochlor 1260 (3.5 mg/L) were observed in 90 days stationary phase. One-way ANOVA test were carried out and showed that the RMs were suitably homogenized, which can be used for proficiency testing. The Relative Standard Deviations (RSDs) of analytical results were 3.51~5.01% for the PCBs RMs in 10 replicates. The expanded uncertainty of PCBs analytical procedure were 0.26~0.49.