| Summary: | 碩士 === 國立交通大學 === 應用化學系 === 91 === Extraction of metal salts using supercritical fluid carbon
dioxide with surfactants
Student：Chih-Chien Wang Advisor：Dr. Tiing Yu
Institute of Applied chemistry
National Chiao Tung University
Abstract
Extraction of metal salts using surfactant-containing supercritical fluid carbon dioxide (SF CO2) was investigated in this study. Only mediocre solubilities of almost all commercially-available surfactants in neat SF CO2 have been reported in the literature. However, adding organic modifier to SF CO2 can increase the surfactant solubilities drastically. The high surfactant solubilities for didodecyldimethylammonium bromide (DDAB) and sodium bis-2-ethylhexyl sulfosuccinate (AOT) ensured formation of reverse micelle in SF CO2 for dissolving metal salts. Extraction of lanthanum chloride heptahydrate, europium chloride and uranyl acetate dehydrate was examined. The recoveries for these three compounds doped in filter papers were 49.18 %, 43.79 % and 43.08 % respectively using AOT-containing SF CO2. Extraction recoveries were also investigated under various temperatures and pressures. Water-to-surfactant ratio had little effect on the extraction recoveries. In addition, a nonionic surfactant, teraethylene glycol n-lauryl ether, was investigated and was found unable to solubilize metal salts in SF CO2.
|
|---|
