Base-catalyzed destruction of PCBs -- New donors, new transfer agents/catalysts
- Environmental Protection Agency, Cincinnati, OH (United States). National Risk Management Research Lab.
The use of hydrogen transfer agents and catalysts to improve the base-catalyzed decomposition of polychlorinated biphenyls (PCBs) was investigated. The reaction proceeded only in the presence of base, but the rate of PCB disappearance increased with increasing amount of hydrogen transfer agents and catalysts. Up to 99+% disappearance of 20,000 mg/kg Aroclor 1242 in paraffinic oil was achieved within 1--4 h at 340--350 C. A three-step mechanism is proposed for the formation of biphenyl, the main product: (1) hydrogen species generated from the paraffin oil; (2) hydrogenation of aromatic catalysts (phenanthrene, anthracene, and alkyl naphthalenes) to form dihydroaromatics, or absorption of hydrogen by hexagonal forms of carbon (graphite or carbon black as present in scrap latex) or transition metals (zero-valent iron and stainless steel); (3) transfer of the hydrogen species to the activated PCBs. The product, biphenyl, may be degraded further or possibly form adducts or polymerize.
- Sponsoring Organization:
- Oak Ridge Inst. for Science and Education, TN (United States); Environmental Protection Agency, Washington, DC (United States)
- OSTI ID:
- 509353
- Journal Information:
- Industrial and Engineering Chemistry Research, Journal Name: Industrial and Engineering Chemistry Research Journal Issue: 5 Vol. 36; ISSN IECRED; ISSN 0888-5885
- Country of Publication:
- United States
- Language:
- English
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