Exchange agent

Hydrogen fluoride, HP, when used alone is a comparatively ineffective exchange agent and replaces only active halogens (13), eg, acyl fluorides from acyl chlorides and ben2otrifluoride [98-08-8] from hen2otrich1 oride (eq. 12). 

Ha.logen Fluorides. These include compounds such as IF, IF, GIF, etc, of which only a few, GIF, GIF, BrP, and IF, are used to some extent. They act both as halogen exchange agents and, in the case of the monofluorides, as addition agents to unsaturated bonds (17). 

Various polyphosphates are effective sequestering agents under appropriate conditions. The best known of these is sodium hexametaphosphate (10.14), the cyclic hexamer of sodium orthophosphate. Further examples are the cyclic trimer sodium trimetaphosphate (10.15), as well as the dimeric pyrophosphate (10.16), the trimeric tripolyphosphate (10.17) and other linear polyphosphates (10.18). All of these polyanions function by withdrawing the troublesome metal cation into an innocuous and water-soluble complex anion by a process of ion exchange as shown in Scheme 10.7 for sodium hexametaphosphate. Hence these compounds are sometimes referred to as ion-exchange agents. 

Replenishing the sodium 10ns of a zeolite of similar ion-exchange agent by treatment with sodium chloride solution. Molecular sieves are regenerated by heat removal of the water (200°C), followed by treatment with an inert gas. 

Linear polyphosphates possess properties very similar to those of cross-linked, solid ion-exchange agents (Thilo, 1955). The behavior of polyphosphates as dissolved ion-exchange agents is yet further evidence of their ability to form complexes with counter-ions. Polyphosphates are known to be very good complexing agents for many metal ions (Van Wazer, 1958). This property is widely exploited in the fractionation of polyphosphates, and for other analytical purposes. 

A sufficient heat transfer must be ensured, i.e. the heat exchanger agent must fit into the fluidised bed. 

The LVFS has been successfully deployed on 11 cruises in the Atlantic and Pacific Oceans. Analyses of the samples have made known the distributions of over 20 elements and have documented the importance of particulate organic matter as a complexing and ion-exchange agent. Furthermore, the results have demonstrated that macroscopic aggregates (fecal matter)... 

In nature, there are large deposits of silica-rich volcanic ashes in coarse amorphous colloidal particles, some of which are fairly pure and quite readily soluble to alkali solutions. They are used often as an industrial source of silica. Impure volcanic ash which contains alumina is used as a detergent, filter aid and mild ion-exchange agent after alkali or acid treatment and as a raw material for the synthesis of zeolite and porous glass. 

The isoelectric points (pi) of most CGTases are about 9, and the pK of DEAE is 9.5, so the DEAE-cellulose column, using DEAE as the exchange agent, is mostly used for the separation of CGTase. This method is often used in the previous preparation process. 

In recent years, a new method for preparing immobihzed CGTase as emerged 10 consecutive lysine residues are linked with enzyme, and then bound on the ion exchange agent. This method is based on the principle that polylysine helps protein to stabilize refold and purify. The characteristics of cormected... 

Uses Catalyst fluorinating agent halogen exchange agent incendiary agent Manuf./Distrib. ABCR http //www.abcr.de] Air Prods, http //www.airproducts.com] Honeywell Perf. Polymers http //www.honeyweiippc.com] http //WWW. honeyweii-piastics. com lodipamide CAS 606-17-7... 

Alginic acid is found in brown algae, where it acts as an ion exchange agent in the cell walls. It is obtained as alginate in England, France, Norway, Japan, Southern California, and Australia by extracting the cell walls with soda solution. 

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