Chelation addition

Utilize a metal chelating additive to help minimize the effect of copper-catalyzed degradation. 

Y. Tapuhi, M. Miller, and B. L. Kanger, Practical considerations in the chiral separation of D,L-amino acids by reversed-phase liquid chromatography using metal chelate additives, J. Chromatogr., 205 325 (1981). 

The technical and economic aspects of wet flue gas simultaneous desulfurization and denitrification systems are presented so that their practicality for utilization by utility industry can be assessed. The emphasis is on the kinetics of the systems based on the employment of ferrous chelates to promote the solubility of NO and the reactivity of NO with SO2 in scrubbing liquors. Analytical techniques are developed for characterizing reaction intermediates and products. Alternative approaches and novel ideas that could develop into a more efficient and cost-effective scrubber system employing metal chelate additives are discussed. 

The improvement over the existing Japanese processes can be made by developing a more efficient ferrous chelate such that it can provide better absorption efficiency for NO, faster reaction rates between NO and S02> and better stability for the ferrous chelate toward oxidation, compared to Fe +(EDTA) or Fe +(NTA) employed in Japanese processes. The development of an efficient and cost-effective method for the reduction of ferric chelate to ferrous chelate without producing dithionate ions could make the process attractive. In addition to these areas, the study of several alternative approaches and novel ideas could develop into a much more efficient and cost-effective scrubber system employing metal chelate additives. 

Lissens, G., Verhaege, M., Pinoy, L. and Verstraete, W. (2003), Electrochemical decomplexing and oxidation of organic (chelating) additives in effluents from surface treatment and metal finishing. 1. Chem. Technol. Biotechnol., 78(10) 1054—1060. 

LePage, J.N. Lindner, W. Davies, G. Seity, D.E. Karger, B.L. Resolution of the optical isomers of dansyl amino acids by reversed phase liquid chromatography with optically active metal chelate additives. Anal. Chem. 1979, 51 (3), 433-435. 

Co 12/Br2, phosphine chelate Addition of inert solvent Acetaldehyde [13]... 

Co Halogen containing complex phosphine chelate Addition of water Ethanol [15]... 

Toward this end, tris(diphenylphenanthroline)ruthenium(II) has been functionalized with arms that are able to chelate additional non-redox-active metal ions to promote hydrolysis of proximal phosphates (97, 98). [Ru(DIP)2(Macro)] +, as this molecule is called, is shown in Fig. 

The CE is quite suited for analysis of these ions too. Because of their relative charge to the small mass, they tend to migrate rapidly in this technique giving fast separation with very high theoretical plate numbers at a low cost per test. Both cations and anions can be analyzed in the same run. The separation can be based on simple free solution CE or based on a suitable chelating additive. In general, cations are measured in a low pH electrolyte containing a UV active species (imidazole... 

W. Lindner, J. N. LePage, G. Davies and B. L. Karger, Reversed-phase separation of optical isomers of Dns-amino acids and peptides using chiral metal chelate additives,/. Chromatogr, 1979, 185, 323-344. 

Located at an "ofif-template" site, we expected the Cl 4 center to be more difficxilt to establish and verify. We were going to have to rely on precedents of acyclic stereoselection, and based on Kishi s empirical observations (ref. 30), hydroxylation of olefin 32b should have given the R epimer 33, preferentially. On the other hand. Cram chelate addition (ref. 31), as elaborated by Still (ref. 32), to the a-benzyloxy ketone 32a, should give the allyl alcohol 34 from which the S-epimer 35 could be derived. Indeed, both processes were entirely stereoselective, and we were able to prepare the two possible products, each as a single isomer. 

In general, the ionic transport in linear or crosslinked swollen polymers containing a low molecular weight polar or ion-chelating additive mainly occurs in the solvent phase [118, 120]. This concept has been applied to develop proton conducting polymeric gel or hydrogel membranes [121-123] which reach conductivity values around 10 S cm at room temperature and are not destroyed or dissolved even at high humidity levels. 

To the main mechanical washing effect, DIPHOTERINE solution adds chelating and amphoteric abilities which aim to stop each of the six possible reactions with chemical substances (acid-base reaction, reduction/oxidation, chelation, addition, substitution, solvation). Its hypertonic property allows it to attract chemical product from tissues to the outside. The solution is applied with a spray or with a shower depending on the stroked area, even if previously an irrigation with water was done previonsly. Nevertheless, some anthors have shown that the better results are obtained when DIPHOTERINE solution is first applied. 

The microstructure of the polybutadiene and polyisoprene produced by anionic polymerization is correlated to the structure of the allylic anion of the active chain end. The charge distribution over this anion is affected greatly by changing counterions, the use of solvating solvents, and the presence of cation chelating additives. 

Detergent chelating additive Methyl vinyl United States 3,852,213 1974 GAP... 

Acid-base reaction Redox Chelation Addition Substitution Solvation... 

Metal Chelate Addition. Metal chelates, such as ferrous ethylene-diamine-tetra-acetate (Fe(II) EDTA), enhance the absorption of NO, into aqueous solutions by reacting quickly with dissolved NO to form the complex Fe(II) EDTA NO. The coordinated NO can react with sulfite and bisulfite ions, forming hydroxylamine-N-disulfonates (HADS) and releasing the ferrous chelate to react with additional NO. When the aqueous solution is a sodium or calcium-based SO2 absorbent, the addition of ferrous chelate results in a combined NO,/SO, control process. 

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