Transport of heavy metals such as Ag is affected by several rate-limiting processes including adsorption and release reactions in soils. In this study, the objective was to qualify adsorption-desorption behavior and transport of silver in the different soils. This study also investigated the influence of the presence of Zn on Ag retention and transport in soils. Kinetic batch adsorption-desorption and column experiments were carried out to investigate the adsorption-desorption and transport of silver in soils having different properties in the presence of Zn. Transport of Ag was carried out using miscible-displacement experiments in water saturated soil columns. For all soils, results indicated that adsorption isotherms for Ag were highly nonlinear with greater affinity for Webster soil. Moreover, the presence of Zn resulted in reduced Ag sorption indicative of competitive behavior. Measured Ag breakthrough results (BTCs) from the column experiments indicated highest Ag mobility in Olivier soil whereas Webster soil exhibited least mobility. This finding is based on the Ag recovered and the retardation of the arrival of Ag in the effluent solution. Furthermore, the presence of Zn resulted in enhanced mobility of Ag. A multireaction and transport model (MRTM) that accounted for nonlinear reversible kinetics and irreversible reactions was capable of describing both Ag and Zn transport in all soil columns.
| Identifer | oai:union.ndltd.org:LSU/oai:etd.lsu.edu:etd-10192013-150711 |
| Date | 11 November 2013 |
| Creators | Zhang, Liyun |
| Contributors | Selim, H. M., Wang, Jim Jian, Tubana, Brenda S. |
| Publisher | LSU |
| Source Sets | Louisiana State University |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lsu.edu/docs/available/etd-10192013-150711/ |
| Rights | unrestricted, I hereby certify that, if appropriate, I have obtained and attached herein a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to LSU or its agents the non-exclusive license to archive and make accessible, under the conditions specified below and in appropriate University policies, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report. |
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