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Presentation Title: Uranium Removal of Contaminated Soils Using Rhamnolipid Coupled with Sequential Extraction Discipline: Chemistry School: Northern Arizona University Presentation Type: Poster Presentation Abstract: Uranium Removal of Contaminated Soils Using Rhamnolipid Coupled with Sequential Extraction Marsha Bitsui, Sara Asselin, Jani C. Ingram, PhD Department of Chemistry & Biochemistry, Northern Arizona University

During the 1940’s through the 1970’s uranium was in demand. Its uses were desired for nuclear warfare. Deposits of uranium were found and mined on the Navajo Reservation. Remains of open pit mining resulted in contaminated soil, water, and food resources. Rhamnolipid, a biosurfactant produced by Pseudomonas aeruguinosa, is known to chelate metals (Maier, R. M. 2000. Applied Microbiology and Biotechnology). In this study, soil samples were collected from the southwest region of the Navajo Reservation near Cameron, AZ, a known mining site, and Leupp, AZ, where no mining occurred. A seven step sequential leaching extraction was paired with a rhamnolipid extraction to determine the amount of uranium removed. The leaching process sequentially extracts hydrosoluble salts, exchangeable cations, carbonates, reducible phases, HCl soluble compounds, oxidizable phases, and insoluble residues from the soil (Quejido, A.J., 2005. Applied Geochemistry). Extracts from untreated soil is compared to extracts from rhamnolipid treated soil, any differences in uranium concentration is assumed to be the result of interactions of the rhamnolipid in the soil. Trace metal analysis is performed using an Inductively Coupled Plasma – Mass Spectrometer. The sequential leaching procedure showed that the majority of uranium in the soil from Cameron was removed in step three (66%); while the majority of uranium removed in the soil from Leupp was removed in step five (48%). The results suggest a different intercalation of the uranium in the two soils which suggests differences in leaching behavior.

Presenter: Marsha Bitsui Tribe: Navajo Primary Email: Biography My name is Marsha Bitsui, I am attending Northern Arizona University as an undergraduate majoring in Biomedical Sciences and obtaining a minor in chemistry. I am Navajo and grew up in Steamboat Canyon, AZ. My clans are Black Streaked Wood, born for the Mexican clan and maternal clan is Red Running Into the Water and my paternal clan is Water's Edge. My future goals are to obtain a masters and doctors degree in chemistry and to keep doing research.


2011 National Conference Student Research Abstracts  
2011 National Conference Student Research Abstracts  

A comprehensive list of the student research topics that will be presented at the AISES 2011 National Conference