Stabilizers Ethylenediaminetetraacetic

The complexers maybe tartrate, ethylenediaminetetraacetic acid (EDTA), tetrakis(2-hydroxypropyl)ethylenediamine, nittilotriacetic acid (NTA), or some other strong chelate. Numerous proprietary stabilizers, eg, sulfur compounds, nitrogen heterocycles, and cyanides (qv) are used (2,44). These formulated baths differ ia deposition rate, ease of waste treatment, stabiHty, bath life, copper color and ductiHty, operating temperature, and component concentration. Most have been developed for specific processes all deposit nearly pure copper metal. 

Kuczynski and Thorns also studied the formation of MV in CdS solution using a cationic surfactant, cetyltrimethylammonium bromide, as a stabiliasr. In the presence of ethylenediaminetetraacetate (EOTA), the MV " yield was greatly increased. EDTA and MV " form a complex with a resultant negative charge, which is electrostatically bound to the cationic CdS surface. The MV " formed is repelled by the positive charge of the cationic stabilizer, a fact which makes the charge separation efficient. 

In most systems, K2 < K[. Otherwise (e.g. the first two dissociation steps for ethylenediaminetetraacetic acid—EDTA) the first hydrogen ion capable of dissociation is stabilized by the presence of the second one and can dissociate only when the second begins to dissociate. As a result both hydrogen ions dissociate in one step. 

Table 1.8 Consecutive stability constants, expressed as logXMX., of complexes of ammonia (A), ethylene diamine (B), diethylenetriamine (C) and the anion of ethylenediaminetetraacetic acid (D4 ) at 20°C and 0.1 mKN03 as indifferent electrolyte. (According to J. Bjerrum and G.

The heavy metals copper, manganese, cobalt and zinc were omitted individually and in combination from MS and B5 media to determine the effect on antibody stability in solution [63]. When IgG, antibody was added to these modified media in experiments similar to the one represented in Figure 2.2, only the B5 medium without Mn showed a significant improvement in antibody retention relative to normal culture media. Nevertheless, protein losses were considerable as only about 30% of the added antibody could be detected in the Mn-free medium after about 5 h. The beneficial effect of removing Mn was lost when all four heavy metals, Cu, Mn, Co and Zn, were omitted simultaneously. The reason for these results is unclear. Addition of the metal chelating agent ethylenediaminetetraacetate (EDTA) had a negligible effect on antibody retention in both MS and B5 media [63]. 

Ferric citrate, molecular formula, 6 638t Ferric ethoxide, 14 533 Ferric ethylenediaminetetraacetic acid (ferric EDTA), 19 261 Ferric ferrocyanide, 8 186 22 810 pigment used in makeups, 7 836t Ferrichromes, 14 557 Ferric ion, acrylamide stabilizer, 1 289 Ferric nitrate bright pickle, 15 375 Ferric oxide... 

Uses Stabilizing rubber latex solvent for albumin, casein, shellac, and sulfur neutralizing oils in antifreeze as a corrosion inhibitor emulsifier adhesives textile lubricants fungicides manufacturing chelating agents such as EOT A (ethylenediaminetetraacetic acid) dimethylol-ethylene-urea resins organic synthesis. 

Ethylenediaminetetraacetic acid, analogs, complexes of, 3 277 chelation by, 3 276-277 cobalt complex of, 3 281 complexes, 3 277-278 formation constant of, 3 273-274 -nickel, 3 17-18 stability of, 3 266-267 reaction with metal ions, 3 62 Ethylene dibromide, irradiation of, 5 196 4,5-Ethylenedithio-1,3-dithiole-2-thione based supramolecular complexes, 46 200-204 Ethylene glycol, 32 4... 

Figure 10.11 Conditional stability constant graphs for (a) ethylenediaminedisuccinic acid [(S,S)-EDS], (b) ethylenediaminetetraacetic acid (EDTA), (c) iminodisuccinic acid (IDS), (d) glutamic acid N,N-diacetic acid (CLDA), and (e) methylglycinediacetic acid (MGDA).

From 1967 to 1969, Kerr published a series of papers on the question of thermal and hydrothermal stabilities of sodium and hydrogen zeolite Y (22-26). These studies indicated that upon removal of about one-third of the aluminum from zeolite Y, using ethylenediaminetetraacetic acid (H4EDTA), the thermal and hydrothermal stabilities were much enhanced. This was observed for both sodium (23) and hydrogen (25) forms of the zeolite. The latter was prepared by careful calcination of an ammonium zeolite from which about 30% of the ammonium and aluminum had been removed. Kerr also showed that the true or normal hydrogen zeolite with... 

Dunkley, W. L., Franke, A. A. and Robb, J. and Ronning, M. J, 1968A. Influence of dietary copper and ethylenediaminetetraacetate on copper concentration and oxidative stability of milk. J. Dairy Sci. 57(6), 863-866. 

For studies involving water, it may only be important to assure that the tracer remains fluid-bound. One can use tritium or almost any metal atom that can be complexed with EDTA (ethylenediaminetetraacetic acid) or DTPA (diethylene-triaminepeutacetic acid) (with a large stability constant). 

The base readily penetrates the hair and promotes bleaching. The addition of stabilizers such as sodium pyrophosphate or sodium oxalate [16,17] retards the decomposition of hydrogen peroxide in the alkaline preparation and thus enhances the bleaching action. The same holds for complexing agents (seques-trants) such as ethylenediaminetetraacetic acid, which hinder decomposition due to traces of heavy metals. Thickening additives include carboxymethyl celluloses, xanthine derivatives, and synthetic polymers. Certain dyes can also be added. 

On Day 2, sub-samples of the effluent are adjusted to pH 3 and 11 (pH 9 for the Cl 8 treatment), and then filtered, aerated or passed through a Cl 8 column. After the manipulations are done, the samples are adjusted back to the initial pH of the effluent (pH / ) and tested for toxicity. The Ethylenediaminetetraacetate (EDTA), sodium thiosulfate and graduated pH adjustments are also conducted on Day 2, but testing is delayed until Day 3. The delay allows EDTA to complex with metals, thiosulfate to react with oxidative substances and metals, and pH to stabilize in the graduated pH test. 

The stabilization of a complex due to cyclization has already been noted, and it might be assumed that where one ring is good, several rings should be better. In the vast majority of cases, stability is indeed increased by incorporation of more than one ring into a structure. The Ca2+ ion, one of the ions with the least tendency toward complex formation, easily snuggles into the hexadentate anion of ethylenediaminetetraacetic add (versene, V) while the anion twists itself into a five-ringed structure (Fig. 6-2). So stable is this chelate that a 0.001 molar solution in water is but 0.01 percent dissociated. 

The stability of some metal complexes is very large. For example, with ethylenediaminetetraacetic acid (EDTA,... 

Foreman, J. K., and Smith, T. D. The nature and stability of the complex ions formed by ter-, quadri-. and sexa-valent plutonium ions with ethylenediaminetetraacetic acid. Part I. pH titrations and ion exchange studies, J. Chem. Soc.,... 

---