PMID- 18991945
OWN - NLM
STAT- MEDLINE
DCOM- 20081203
LR  - 20181113
IS  - 1749-6632 (Electronic)
IS  - 0077-8923 (Print)
IS  - 0077-8923 (Linking)
VI  - 1140
DP  - 2008 Oct
TI  - Mixed redox catalytic destruction of chlorinated solvents in soils and 
      groundwater.
PG  - 435-45
LID - 10.1196/annals.1454.044 [doi]
AB  - A new thermocatalytic method to destroy chlorinated solvents has been developed 
      in the laboratory and tested in a pilot field study. The method employs a 
      conventional Pt/Rh catalyst on a ceramic honeycomb. Reactions proceed at moderate 
      temperatures in the simultaneous presence of oxygen and a reductant (mixed redox 
      conditions) to minimize catalyst deactivation. In the laboratory, stable 
      operation with high conversions (above 90% at residence times shorter than 1 s) 
      for perchloroethylene (PCE) is achieved using hydrogen as the reductant. A molar 
      ratio of H(2)/O(2)= 2 yields maximum conversions; the temperature required to 
      produce maximum conversions is sensitive to influent PCE concentration. When a 
      homologous series of aliphatic alkanes is used to replace hydrogen as the 
      reductant, the resultant mixed redox conditions also produce high PCE 
      conversions. It appears that the dissociation energy of the C-H bond in the 
      respective alkane molecule is a strong determinant of the activation energy, and 
      therefore the reaction rate, for PCE conversion. This new method was employed in 
      a pilot field study in Tucson, Arizona. The mixed redox system was operated 
      semicontinuously for 240 days with no degradation of catalyst performance and 
      complete destruction of PCE and trichloroethylene in a soil vapor extraction gas 
      stream. Use of propane as the reductant significantly reduced operating costs. 
      Mixed redox destruction of chlorinated solvents provides a potentially viable 
      alternative to current soil and groundwater remediation technologies.
FAU - Gao, Song
AU  - Gao S
AD  - Department of Atmospheric Sciences, The University of Arizona, Tucson, Arizona, 
      USA. song.gao@arizona.edu
FAU - Rupp, Erik
AU  - Rupp E
FAU - Bell, Suzanne
AU  - Bell S
FAU - Willinger, Martin
AU  - Willinger M
FAU - Foley, Theresa
AU  - Foley T
FAU - Barbaris, Brian
AU  - Barbaris B
FAU - Saez, A Eduardo
AU  - Saez AE
FAU - Arnold, Robert G
AU  - Arnold RG
FAU - Betterton, Eric
AU  - Betterton E
LA  - eng
GR  - P42 ES004940/ES/NIEHS NIH HHS/United States
GR  - P42 ES004940-200027/ES/NIEHS NIH HHS/United States
GR  - P42 ES04940/ES/NIEHS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
PL  - United States
TA  - Ann N Y Acad Sci
JT  - Annals of the New York Academy of Sciences
JID - 7506858
RN  - 0 (Alkanes)
RN  - 0 (Soil Pollutants)
RN  - 0 (Solvents)
RN  - 0 (Water Pollutants, Chemical)
RN  - 4R7X1O2820 (Chlorine)
RN  - S88TT14065 (Oxygen)
SB  - IM
MH  - Alkanes
MH  - Biodegradation, Environmental
MH  - Catalysis
MH  - Chemistry/*methods
MH  - Chemistry Techniques, Analytical/instrumentation/methods
MH  - Chlorine/*analysis
MH  - Environmental Monitoring/methods
MH  - Environmental Pollution
MH  - *Oxidation-Reduction
MH  - Oxygen/analysis/chemistry
MH  - Soil Pollutants/*analysis
MH  - Solvents/*chemistry
MH  - Temperature
MH  - Water Pollutants, Chemical/metabolism
PMC - PMC2867620
MID - NIHMS193640
COIS- Conflicts of Interest The authors declare no conflicts of interest.
EDAT- 2008/11/11 09:00
MHDA- 2008/12/17 09:00
PMCR- 2010/05/11
CRDT- 2008/11/11 09:00
PHST- 2008/11/11 09:00 [pubmed]
PHST- 2008/12/17 09:00 [medline]
PHST- 2008/11/11 09:00 [entrez]
PHST- 2010/05/11 00:00 [pmc-release]
AID - NYAS1140044 [pii]
AID - 10.1196/annals.1454.044 [doi]
PST - ppublish
SO  - Ann N Y Acad Sci. 2008 Oct;1140:435-45. doi: 10.1196/annals.1454.044.