Linked Life Data

15721534

Source:http://linkedlifedata.com/resource/pubmed/id/15721534

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-3
pubmed:dateCreated
2005-2-21
pubmed:abstractText
Ferrous iron (Fe(II)) in combination with Portland cement is effective in reductively dechlorinating chlorinated organics and can be used to achieve immobilization and degradation of contaminants simultaneously. Reactivities of chlorinated ethylenes (perchloroethylene (PCE), trichloroethylene (TCE), 1,1-dichloroethylene (1,1-DCE), vinyl chloride (VC)) in Fe(II)/cement systems were characterized using batch slurry reactors. Reduction kinetics of the chlorinated ethylenes were sufficiently fast to be utilized for the proposed treatment scheme, and were described by a pseudo-first-order rate law. The order of reactivity of the chlorinated ethylenes was TCE>1,1-DCE>PCE>VC. Reduction of TCE and PCE mainly yielded acetylene, implying that the transformation of the two compounds occurred principally via reductive beta-elimination pathways. Transformation of 1,1-DCE and VC gave rise to primarily ethylene, implying that major degradation pathways were a reductive alpha-elimination for the former and a hydrogenolysis for the latter. The reactivity of the Fe(II)/cement systems in dechlorinating TCE was proportional to Fe(II) dose when the Fe(II)/cement mass ratio varied between 5.6 and 22.3%. The Fe(II)/cement systems with a higher Fe(II) loading were less extensively affected by pH in reductive reactions for TCE than in the previous experiments with PCE or chlorinated methanes. Amendment of Fe(II)/cement systems with Fe(III) addition was found effective in increasing the reactivity in the previous study, but the current findings indicated that the extent to which the reaction rate increased by the amendment might be dependent on the source of the cement and/or the compounds tested.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0304-3894
pubmed:author
pubmed:issnType
Print
pubmed:day
14
pubmed:volume
118
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
103-11
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Reactivity of Fe(II)/cement systems in dechlorinating chlorinated ethylenes.
pubmed:affiliation
Department of Environmental Engineering, Pusan National University, 30 Jangjeon-Dong, Keumjeong-Gu, Busan 609-735, Republic of Korea.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't