Ion exchange principle

An ISE for acetylcholine [11 ] is based on the same principle (ion-exchanger solution Coming No. 476200) and has been used for determination of choline... 

Background and principles Ion-exchange chromatography is a form of adsorption chromatography lhal relies on Ihe ionic and eleclroslalic properties of charged... 

Purification techniques, methods for the purification of peptides and proteins. Analysis and purification of naturally occurring peptides and of synthetic peptides makes use of different separation techniques. Partitioning of the analyte between a solution and a solid phase is the most exploited principle. Ion-exchange and electrophoresis methods... 

See alsa Amperometry. Carbohydrates Sugars -Chromatographic Methods. Derivatization of Analytes. Electrophoresis Principles. Flow Injection Analysis Principles. Ion Exchange Principles. Liquid Chromatography Column Technology Chiral Analysis of Amino Acids. Sensors Amperometric Oxygen Sensors. 

In principle, ion-exchange is based on an equilibrium (scheme 14.3). One cation is preferentially absorbed (M ) by the resin over another cation (M). The position of this equilibrium depends on two major factors these are the relative concentrations of M and M and the relative affinity of the resin for M and M. If the ion-exchange resin is simply stirred with the effiuent the amount of M adsorbed from solution can never be better than that determined by the equilibrium value for a given temperature and pressure. 

The student who is interested in details of the physical principles involved and of further applications of ion exchange should consult Ion Exchanges in Organic and Biochemistry by Calvin Calmon and T. R. E. Kressman. (Inter- cience Publication Inc., New York.)... 

Process Description lectrodialysls (ED) is a membrane separation process in which ionic species are separated from water, macrosolutes, and all uncharged solutes. Ions are induced to move by an electrical potential, and separation is facilitated by ion-exchange membranes. Membranes are highly selective, passing either anions or cations andveiy little else. The principle of ED is shown in Fig. 22-56. 

The two examples that have been given are simple and basic, and illustrate the principles of a TLC separation. Ion exchange material can also be bonded to the silica, allowing ionic interactions to be dominant in the stationary phase and, thus. 

Ion Exchange Chromatography - Basic principles of ion exchange chromatography and studies conducted from Texas A M University. http //ntri.tamuk.edu/fplc/ion.html. 

Owens, Dean L., Practical Principles of Ion Exchange Water Treatment, Tall Oaks Publishing, Inc., Voorhees NJ, 1985. 

Ion chromatography (IC) is a relatively new technique pioneered by Small et al.25 and which employs in a novel manner some well-established principles of ion exchange and allows electrical conductance to be used for detection and quantitative determination of ions in solution after their separation. Since electrical conductance is a property common to all ionic species in solution, a conductivity detector clearly has the potential of being a universal monitor for all ionic species. 

Investigations in aqueous systems have established many of the fundamental principles of ion exchange as well as providing useful applications. The scope of the ion exchange process has, however, been extended by the use of both organic and mixed aqueous-organic solvent systems.32,33... 

A design feature of ion-exchange plant whereby the regeneration flow or backwash flow are in the opposite direction to the service flow. Also, a principle used in heat exchangers whereby the medium being heated flows in the opposite direction to the medium supplying the heat. 

S-2.2.2 Neutral Carrier Electrodes hi addition to charged liquid ion exchangers, liquid-membrane electrodes often rely on the use of complex-forming neutral carriers. Much effort has been devoted to the isolation or synthesis of compounds containing cavities of molecular dimensions. Such use of chemical recognition principles has made an enormous impact upon widespread acceptance of ISEs. The resulting neutral carriers can be natural macrocyclic molecules or synthetic crown... 

A wide variety of solid materials are used in catalytic processes. Generally, the (surface) structure of metal and supported metal catalysts is relatively simple. For that reason, we will first focus on metal catalysts. Supported metal catalysts are produced in many forms. Often, their preparation involves impregnation or ion exchange, followed by calcination and reduction. Depending on the conditions quite different catalyst systems are produced. When crystalline sizes are not very small, typically > 5 nm, the metal crystals behave like bulk crystals with similar crystal faces. However, in catalysis smaller particles are often used. They are referred to as crystallites , aggregates , or clusters . When the dimensions are not known we will refer to them as particles . In principle, the structure of oxidic catalysts is more complex than that of metal catalysts. The surface often contains different types of active sites a combination of acid and basic sites on one catalyst is quite common. 

The adsorption process, in principle, is an anion-exchange process which is restricted only to the surface of the activated charcoal. This fact makes the loading or the exchange capacity of activated charcoal to be relatively smaller in comparison with ion-exchange resins, and it is for this reason that charcoals are quite often treated suitably to improve their loading capacities. The surface and the pore structure characteristics of activated carbon are the important factors upon which its industrial applications depend. 

---