Cation exchange resin, radioactivity

The product nuclei from the target are collected on thin Au foils. These foils are dissolved and the hulk of the fission product and Induced radioactivity are removed ty a combination of solvent-extraction and Ion exchange techniques. The actinide fraction Is separated into the components by rapid elution from Dowex-50 cation-exchange resin, with Cf-hydroxy isobutyric acid as the eluant (42). 

The radiochemical procedure for the determination of Cs in aqueous samples is based on the batch extraction of caesium onto a microcrystalline cation exchanger, ammonium molybdophosphate (AMP), and subsequent purification from potassium and rubidium activities by ion-exchange separation using a strongly acidic cation exchange resin (BIO-REX-40). Natural K and Rb have radioactive isotopes that interfere with the beta counting of Cs. The purification of caesium is also necessary to determine the chemical recovery. 

The copper of ascorbic acid oxidase is firmly boimd, and is not removed by a cation exchange resin. When radioactive Cu is used to study exchange of copper, no isotope is incorporated into the enzyme imder any conditions except those that permit enzyme activity. Under these conditions there is both exchange of copper and inactivation of the enzyme. It is not known whether these two processes are related. It has been suggested that the exchange reaction implies a reversible reduction of copper during enzyme activity, and that only the cuprous form ex-... 

A sensitive method for analysis of the constituent monosaccharide components of glycoproteins involved sequential acid hydrolysis, borotrltide reduction, re-N-acetylation, and radioactivity detection after separation of neutral alditols and amino-alditols on a cation-exchange resin in the Pb -form at 80°C. ... 

This is a process by which ions that are dissolved in water are transferred to, and held by, a solid material or exchange resin. It is a process commonly used for softening water. When water containing dissolved cations associated with hardness (e.g., Ca, Mg2+, Fe2+, and Mn2+), as well as heavy metal or radioactive cations, contacts the resin, the cations are exchanged for the loosely held sodium ions on the resin. The process makes the water soft. ... 

One of the basic problems of the nuclear power industry is avoidance of environmental pollution, which is directly related to the necessity of reliable burial of radioactive waste. One type of waste comprises ion-exchange resins used to purify process waters and render them free of radioactive cations. The problem of disposal of used radioactive ion-exchange resins is rather difficult and we have suggested using Silor composition for this purpose. This composition envelops the swollen... 

The tetraethyl ester of 1,1-vinylidenediphosphonic acid has been used to make cross-linked copolymers which are ion-exchange resins with selective chelation properties for toxic metal cations (78). An alternative method for introducing the diphosphonic acid structure is by reaction of a methylenediphosphonic ester with chloromethylated styrene copolymer beads (79). At least one such resin class, Diphonix, also containing sulfonic acid and other functional groups, has shown promise for treatment of radioactive waste and for iron control in copper electrowinning (80,81). 

Ion exchange is used in the metal plating industry to purify rinse water and spent plating bath solutions. Cation exchangers ranove cationic metal species, such as Cu, from such solutions. Anion exchangers remove anionic cyanide metal complexes, such as Ni(CN), and chromium(VI) species, such as CrOI. Radionuclides can be ranoved from radioactive and mixed radioactive/ hazardous chemical waste by ion exchange resins. 

For purer water quality, the water may be totally demineralized by mixed beds of polymeric resins which exchange in turn hydrogen ions for all cations and hydroxyl ions for all anions, effectively producing pure HjO from a raw water stream. Such highly purified waters are required for boilers operating from about 6 MPa and for all nuclear boilers (to avoid radioactive half-life of water-borne salts). 

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