Adsorption and Chromatography

Adsorption is a physical phenomenon in which some components adsorbates) in a fluid (liquid or gas) move to, and accumulate on, the surface of an appropriate solid adsorbent) that is in contact with the fluid. With the use of suitable adsorbents, desired components or contaminants in fluids can be separated. In bioprocesses, the adsorption of a component in a liquid is widely performed by using a variety of adsorbents, including porous charcoal, silica, polysaccharides, and synthetic resins. Such adsorbents of high adsorption capacities usually have very large surface areas per unit volume. The adsorbates in the fluids are adsorbed at the adsorbent surfaces due to van der Waals, electrostatic, biospecific, or other interactions, and thus become separated from the bulk of the fluid. In practice, adsorption can be performed either batchwise in mixing tanks, or continuously in fixed-bed or fluidized-bed adsorbers. In adsorption calculations, both equilibrium relationships and adsorption rates must be considered. 

In gas or liquid column chromatography, the adsorbent particles are packed into a column, after which a small amount of fluid containing several solutes to be separated is applied to the top ofthe column. Each solute in the applied fluid moves down the column at a rate determined by the distribution coefficient between the adsorbent and the fluid and emerges at the outlet of the column as a separated band. Liquid column chromatography is the most common method used in the separation of proteins and other bioproducts. 

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As may be gathered, the held of ion-exchange adsorption and chromatography is far too large to be treated here in more than this summary fashion. Refs. 195 and 196 are useful monographs. 

See, for example, A. Weiseberger (Editor), Technique of Organic Chemistry. Volume V. Adsorption and Chromatography. Interacience (1951) H. H. Strain, Chromatographic Adsorption Analysis, Interacience (1945). 

Wankat PhC (1986) Large-Scale Adsorption and Chromatography, CRC Press Inc Baca Raton, Florida... 

Tomarelli et al. (T32) separated, after acid hydrolysis and purification by charcoal adsorption and chromatography, a crystalline compound from hog gastric mucin which was highly active in L. bifidus assays. It was reported to be a disaccharide containing acetylglucosamine. 

Department of Adsorption and Chromatography, Faculty of Chemistry, Maria Curie-Sklodowska University, 20-031 Lublin, Poland... 

Gu, T., Tsai, G.-J., Tsao, G. T. Multicomponent adsorption and chromatography with uneven saturation capacities, AIChE /., 1991, 37(9), 1333-1340. 

Wankat, P.C. Large Scale Adsorption and Chromatography CRCPress Boca Raton, FL, 1986 Vol.II. 

The investigation of interactions of fullerene molecules with organic molecules may bring essential contribution to the study of physicochemical properties of fullerenes. The most distinctly intermolecular interactions are manifested in adsorption and chromatography based on these interactions. The study of adsorption at small coverage of different organic molecules on fullerene crystal surface makes it possible to determine thermodynamic characteristics of adsorption by means of which the intermolecular interactions can be described. 

Wankat, P. C., 1986. Large Scale Adsorption and Chromatography (2 vols.). Boca Raton, FL CRC Press. Wankat, P. C., 1990. Rate Controlled Separations. London Elsevier Applied Science. 

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