The equilibrium behavior of phenol in the presence of supercritical carbon dioxide and soil /
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| Other Authors: | , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1990.
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| Subjects: | |
| Online Access: | ProQuest, Abstract Link to OAKTrust copy |
| Abstract: | This project used supercritical carbon dioxide to extract an organic pollutant (phenol) from soil. Supercritical carbon dioxide has been heated and compressed beyond its critical point and has properties between those of a liquid and gas. This supercritical state has the advantage that the carbon dioxide solvent power is directly related to its density which is controlled by pressure. To demonstrate the use of supercritical carbon dioxide to extract phenol from soil, the equilibrium behavior was investigated using a novel methodology. The technique allows samples to be taken near process conditions. The extent of extraction and a mass distribution coefficient were used to interpret the experimental data. The parameters studied were the soil, the temperature, the pressure, the presence of other chemicals, and the amount of phenol in the system. Six Texas soils were used to determine how the soil affects the extraction of phenol. The extent of phenol extraction depended on the soil's surface area and the organic mass fraction. The distribution coefficient behavior depended on the temperature and pressure, while the extent of extraction was slightly affected by the temperature or pressure. The extraction of phenol in the presence of water (soil moisture), methanol (as an entrainer), and benzene (a co-pollutant) was determined. The results showed that the presence of other chemicals does affect the extraction of phenol. This extraction behavior was interpreted using a hypothesis based on the hydrophilic/hydrophobic natures of the carbon dioxide and the other chemicals present. The last series of experiments involved varying the amount of phenol while keeping constant the temperature, pressure, and amount of soil. The results suggest that a process similar to pore condensation may be controlling the extraction. All of these results indicate that the supercritical extraction of a solute from a solid matrix is much more complex than indicated by previous work. |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Chemical engineering." |
| Physical Description: | xi, 86 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |