Type of Document Dissertation Author Rodarte, Alma Isabel Marín URN etd-07282008-134126 Title Predispersed solvent extraction of copper from dilute aqueous solution Degree PhD Department Chemical Engineering Advisory Committee
Advisor Name Title Conger, William L. Committee Co-Chair Wills, George B. Committee Co-Chair Beyer, Gerhard H. Committee Member Boardman, Gregory D. Committee Member Michelsen, Donald L. Committee Member Keywords
Date of Defense 1991-09-20 Availability restricted Abstract
Predispersed Solvent Extraction (POSE) was used to extract copper ions from dilute acidic aqueous solution. POSE is based on the principle that there is no need to comminute both phases. All that is necessary is to comminute the solvent phase prior to contacting it with the feed. This is done by converting the solvent into aphrons. which are micron-sized globules encapsulated in a soapy film. Since the aphrons are so small, it takes a long time for the solvent to rise to the surface under the influence of gravity alone. Therefore, the separation is expedited by piggy-back flotation of the aphrons on especially prepared gas bubbles, which are somewhat larger than aphrons and are called colloidal gas aphrons (CGA).
Polyaphrons of various types were studied extensively. The apparatus used to generate the polyaphrons was upgraded. The residence time distribution of a liquid in the polyaphron generator was determined. The particle size distribution of polyaphrons was determined using photo-microscopy and sedimentation among other methods.
Batch tests were done using both conventional and POSE. Results showed that POSE approaches equilibrium much faster than conventional extraction. Equilibrium isotherms were drawn and empirical equilibrium reJationships were developed. The dynamics of the kinetics of the extraction was modeled using film theory.
Equipment for the POSE process was built. Experiments were carried out in continuous mode and the process was optimized. An empirical statistical equation was developed for the extraction process in continuous mode. Depending on the aqueous to solvent ration, more than 99% copper can be extracted.
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