Linked Life Data

18991945

Source:http://linkedlifedata.com/resource/pubmed/id/18991945

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
2008-11-10
pubmed:abstractText
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.
pubmed:grant
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1749-6632
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
1140
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
435-45
pubmed:dateRevised
2010-9-22
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Mixed redox catalytic destruction of chlorinated solvents in soils and groundwater.
pubmed:affiliation
Department of Atmospheric Sciences, The University of Arizona, Tucson, Arizona, USA. song.gao@arizona.edu
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural