Elution agents for

Sodium trimetaphosphate was used as an eluting agent for the removal of heavy metals such as Pb, Cd, Co, Cu, Fe, Ni, Zn and Cr from aqueous solutions. Distribution coefficients of these elements have been determined regarding five different concentrations of sodium trimeta phosphate (3T0 M 5T0 M 0.01 M 0.05 M 0.1 M) on this resin. By considering these distribution coefficients, the separation of heavy metals has been performed using a concentration gradient of 3T0 - 5T0 M sodium trimetaphosphate. Qualitative and quantitative determinations were realized by ICP-AES. 

Other eluting agents for Pu adsorbed on anion exchange resin in the nitrate system are hydroxylamine and 0.36 M HCl - 0.01 M HF. 43... 

Kutun, S. and Akseli, A., New elution agent, sodium trimetaphosphate, for the separation and determination of rare earths by anion-exchange chromatography, /. Chromatogr. A, 847, 261, 1999. 

A solution of 250 mg of poly(acrylamide) from Example 3-9 in 25 ml of distilled water is introduced at the top of the column. At the same time the collection of the eluate is commenced, taking 10 ml portions (measuring cylinder) for each fraction.Theflow time under these conditions is about 10 ml/h. When the meniscus of the poly(acrylamide) solution reaches the gel layer, distilled water is added to the column as eluting agent. 

Figure 15.8 Original elution data corresponding to the discovery of mendelevium, February 18, 1955. The curves for einsteinium-253 (given the old symbol E253) and californium-246 are for a-particle emission. (Dowex 50 ion exchange resin was used, and the eluting agent was ammonium a-hydroxyisobutyrate.)...

Traditionally, isomers formed by polyamines and inert metal centres have been separated by fractional crystallization. More recently, the techniques of column chromatography have been used, especially for Co111 hexamines.31,3S Both geometric and optical isomers can be separated by judicious use of eluting agents and under favorable conditions isomers occurring at the 1 % level can be isolated. 

Figure 8.1. Chromatograms produced on a 100 mm column of an amino acid analyser with 0.3 N sodium citrate solution (pH 7.00) as eluting agent (a) standard solution containing 1 unol/ml of each amino acid (b) 30 g of cabbage extract purified with Dowex 50-X8 in the ammonium form (0.97 mg of S-methylmethionine) and (c) the same sample as for (b) but after treatment at pH 10.0 for 30 minutes at 120 C. MMS S-methylmethionine, fils histidine, lys lysine, orn ornithine, arg arginine. From [12]...

Step 2. Write a procedure for testing other eluting agents in the style of the experiments in this laboratory manual to delineate each step in sufficient detail. 

The. applications of ion-exchange chromatography are exemplified by the selection shown in table 4.18. Among the most notable are the separation of lanthanides and actinides using a citrate, lactate or EDTA eluting agent the separation of many metals as halide complexes on anionic resins and the separation of amino-acids with citrate buffers. The use of pressurized systems for complex mixtures is likely to become more widespread in the future. 

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