Sorption and desorption processes affecting the enrichment of the fluorocarbons CCl₂F₂ and CCl₃F in ground water

Persistent Link:
http://hdl.handle.net/10150/191741
Title:
Sorption and desorption processes affecting the enrichment of the fluorocarbons CCl₂F₂ and CCl₃F in ground water
Author:
Russell, Ann Drayton.
Issue Date:
1981
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Field measurements of CCl₃F and CCl₂F₂ in ground water have shown that concentrations in recharge areas may be higher than those in water at equilibrium with the atmosphere. This research tested the hypothesis that sorption and desorption of fluorocarbons from grain surfaces in response to changes in soil moisture content are responsible for this enrichment. Soil slurry experiments were performed to determine whether aqueous fluorocarbon concentrations increased when water came into contact with dry soils. In all slurries, the aqueous CCl₃F concentration increased significantly, whereas the CCl₂F₂ concentrations increased in all but two of the slurries. The percent increase of both compounds correlated well with soil properties such as percent clay and percent organic matter. Column experiments were carried out to obtain distribution coefficients (Kd) for CCl₃F and CCl₂F₂ on dry soils. These values were 3.02 and 3.20 cm³/g, respectively, and the values for Kd on saturated sand were 0.67 and 0.360 cm 3 ig for CCl₃F and CCl₂F₂, respectively. The difference in magnitude of Kd for saturated and dry media suggests that significant amounts of both fluorocarbons desorb from grain surfaces when dry soil is wetted, causing enrichment of aqueous fluorocarbon concentrations.
Type:
Thesis-Reproduction (electronic); text
LCSH Subjects:
Hydrology.; Chlorofluorocarbons -- Environmental aspects.; Water Fluorocarbon content.; Groundwater -- Pollution.; Radioactive tracers in hydrogeology.
Degree Name:
M.S.
Degree Level:
masters
Degree Program:
Hydrology and Water Resources; Graduate College
Degree Grantor:
University of Arizona
Committee Chair:
Thompson, Glenn M.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleSorption and desorption processes affecting the enrichment of the fluorocarbons CCl₂F₂ and CCl₃F in ground wateren_US
dc.creatorRussell, Ann Drayton.en_US
dc.contributor.authorRussell, Ann Drayton.en_US
dc.date.issued1981en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractField measurements of CCl₃F and CCl₂F₂ in ground water have shown that concentrations in recharge areas may be higher than those in water at equilibrium with the atmosphere. This research tested the hypothesis that sorption and desorption of fluorocarbons from grain surfaces in response to changes in soil moisture content are responsible for this enrichment. Soil slurry experiments were performed to determine whether aqueous fluorocarbon concentrations increased when water came into contact with dry soils. In all slurries, the aqueous CCl₃F concentration increased significantly, whereas the CCl₂F₂ concentrations increased in all but two of the slurries. The percent increase of both compounds correlated well with soil properties such as percent clay and percent organic matter. Column experiments were carried out to obtain distribution coefficients (Kd) for CCl₃F and CCl₂F₂ on dry soils. These values were 3.02 and 3.20 cm³/g, respectively, and the values for Kd on saturated sand were 0.67 and 0.360 cm 3 ig for CCl₃F and CCl₂F₂, respectively. The difference in magnitude of Kd for saturated and dry media suggests that significant amounts of both fluorocarbons desorb from grain surfaces when dry soil is wetted, causing enrichment of aqueous fluorocarbon concentrations.en_US
dc.description.notehydrology collectionen_US
dc.typeThesis-Reproduction (electronic)en_US
dc.typetexten_US
dc.subject.lcshHydrology.en_US
dc.subject.lcshChlorofluorocarbons -- Environmental aspects.en_US
dc.subject.lcshWater Fluorocarbon content.en_US
dc.subject.lcshGroundwater -- Pollution.en_US
dc.subject.lcshRadioactive tracers in hydrogeology.en_US
thesis.degree.nameM.S.en_US
thesis.degree.levelmastersen_US
thesis.degree.disciplineHydrology and Water Resourcesen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.chairThompson, Glenn M.en_US
dc.contributor.committeememberDavis, Stanley N.en_US
dc.contributor.committeememberWilson, Lorne G.en_US
dc.identifier.oclc212846256en_US
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