Adsorptive-bubble separation enriching

By using an anionic collector and external reflux in a combined (enriching and stripping) column of 3.8-cm (1.5-in) diameter with a feed rate of 1.63 ni/n [40 gal/(h ft )] based on column cross section, D/F was reduced to 0.00027 with C JCp for Sr below 0.001 [Shou-feld and Kibbey, Nucl. AppL, 3, 353 (1967)]. Reports of the adsubble separation of 29 heavy metals, radioactive and otheiwise, have been tabulated [Lemlich, The Adsorptive Bubble Separation Techniques, in Sabadell (ed.), Froc. Conf. Traces Heavy Met. Water, 211-223, Princeton University, 1973, EPA 902/9-74-001, U.S. EPA, Reg. 11, 1974). Some separation of N from by foam fractionation has been reported [Hitchcock, Ph.D. dissertation. University of Missouri, RoUa, 1982]. 

A few simple differences in the properties of immiscible phases make possible their relative displacement. Most simply, if the phases have different densities they will automatically acquire a relative motion in a gravitational field. Thus in adsorptive bubble separation methods, bubbles injected into a column of liquid rise toward the upper surface. Separation occurs by combining the relative enrichment of components at the bubble interface with the continuous displacement of bubbles through the liquid [33-35]. 

According to the collection procedure for the enriched gas-liquid and/or gas-solid interfaces, adsorptive bubble separation processes or techniques can also be divided into two large categories (a) foam separation, which involves the production of foam in the process, and (b) nonfoaming adsorptive bubble separation, which involves no production of foam. Foam separation can be further subdivide into foam fractionation and flotation. Nonfoaming adsorptive bubble separation, however, can be further subdivided into bubble fractionation, solvent sublation, and noirfoaming flotation. Lemlich (84) and Wang (1,75) provided the definitions of these technical terms in their books. 

In the batch adsorptive bubble separation processes, a feed solution was introduced to a bubble separation column (or chamber) containing an aqueous solution of surface-active materials. Surface-active solutes or complexes that are hydrophobic and readily attachable to the air bubbles are carried up to the surface of the water by the bubbles. The enriched material at the top (whether collapsed foam from a foam separation column or overflow liquid from a nonfoaming bubble separation column) and the clarified drain solution at the bottom are withdrawn from the system. The overall material balance for the process is as follows ... 

The recovery of proteins from cultivation medium is usually performed by precipitation, adsorption, flocculation, extraction and ultrafiltration [62-64]. The adsorptive bubble separation techniques were considered in a book by Lemlich [65]. Foam flotation was described by Wilson and Clark [66]. However, in these books, no systematic investigations on the influence of equipment and operating parameters on protein enrichment and separation factors were published. 

Buga, L.A., Enantioselective Enrichment of Selected Pesticides by Adsorptive Bubble Separation, Dissertation Thesis, Technical University from Miinchen, 2005. 

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