Show simple item record

dc.creatorGuo, Yangen_US
dc.descriptionDue to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to, referencing the URI of the item.en_US
dc.descriptionIncludes bibliographical references.en_US
dc.descriptionIssued also on microfiche from Lange Micrographics.en_US
dc.description.abstractThe adsorption equilibria of four volatile organic compounds, n-hexane, toluene, methanol and chlorobenzene on Highbank #4471 soil were measured by a dynamic response technique based on frontal analysis chromatography. The adsorption isotherms were BET type 11 isotherms, which indicates multilayer adsorption on soil. The heats of adsorption indicate physical adsorption. Competitive adsorption of organic mixtures on soil was assessed by measuring the adsorption equilibria of binary mixtures of volatile organic compounds by using the same technique. The binary mixtures systems were hexane-toluene(non-polar, non-polar), methanol-toluene(polar, non-polar), and methanol-chlorobenzene(polar, polar). The presence of two organics reduced each organic's uptake on soil. The adsorption isotherms of hexane-toluene system were BET type 11. With the presence of methanol, the isotherms exhibited a different behavior. The isotherms progressively became BET type III when the concentration of methanol was high. The desorption of pure compounds and binary mixtures from the soil were also investigated. The desorption profiles were linked to the shape of the adsorption isotherms and showed a two-step behavior. The first step corresponded to the desorption of the multilayers and the second step to the monolayer desorption. The second step was the rate-controlling step for the overall desorption process. The adsorption isotherms of single components on soil were modeled by using the BET isotherin. The extended BET model, the potential theory and the ideal adsorbed solution theory for mixture adsorption were also evaluated for prediction of the experimental results for binary adsorption. All models failed for prediction of the BET type III isotherms when methanol was present at high concentrations. For the n-hexane and toluene system, the IAST and extended BET models can predict the amount adsorbed. The potential theory works well at a low concentrations of n-hexane and under-predicted at high concentrations of n-hexane. For cases when methanol was present, only the IAST model can predict the adsorbed amount at conditions where concentrations of methanol are low.en_US
dc.publisherTexas A&M Universityen_US
dc.rightsThis thesis was part of a retrospective digitization project authorized by the Texas A&M University Libraries in 2008. Copyright remains vested with the author(s). It is the user's responsibility to secure permission from the copyright holder(s) for re-use of the work beyond the provision of Fair Use.en_US
dc.subjectchemical engineering.en_US
dc.subjectMajor chemical engineering.en_US
dc.titleAdsorption and desorption of binary mixtures of volatile organic contaminants on soilen_US
dc.typeThesisen_US engineeringen_US
dc.format.digitalOriginreformatted digitalen_US

Files in this item


This item appears in the following Collection(s)

Show simple item record

This item and its contents are restricted. If this is your thesis or dissertation, you can make it open-access. This will allow all visitors to view the contents of the thesis.

Request Open Access