Cobalt addition

Table I. Product Compositions from the Catalysts ZSM-5 (11.1% Fe) and ZSM-5 (5.6% Fe, 4.5% Co), in a Berty Reactor, Showing the Influence of Cobalt Addition to the Catalyst.

McLaren R.G., Lawson D.M., Swift R.S., Purves D. The effects of cobalt additions on soil and herbage cobalt concentrations in some S. E. Scotland pastures. J Agri Sci 1985 105, 347-363. 

The formation of multinuclear clusters is much more favorable for rhodium than for cobalt. Additional evidence was obtained in comparative hydroformylation rate studies of 1-heptene and of cyclohexene at 75°C and 150 atm 1/1 H2/CO (19). For the acyclic olefin the kinetics followed the kinetic expression (except at low olefin) ... 

Davis and coworkers35 37 have also reported on the FTS on silica-supported cobalt. Addition of water in the feed to the FTS over a 12.4% Co/Si02 gave permanent loss in activity when the water fraction exceeded 25%.35,36 This catalyst... 

Some years ago, a cobalt additive was used by some beer makers to maintain a foam head on their beer. Those who imbibed excessively developed what is known as beer drinkers syndrome, which caused some deaths from enlarged and flabby hearts. 

Elemental composition Co 73.42%, O 26.58%. The nitric acid extract of the oxide may be analyzed for cobalt by various instrumental methods (see Cobalt). Additionally, the solid crystalline product may be characterized by x-ray techniques. 

These cobaltous addition compounds, therefore, resemble the preceding group of additive substances rather than the eobaltic salts, and the series illustrate the statement previously made that the most highly saturated compounds of an element have greater capacity for the formation of complex addition compounds. In this connection, for example, one might compare the relative instability of hexammino-cobaltous chloride, [Co(NH3)6]Cl2, with the high stability of the ammine of the more saturated eobaltic chloride, hexammino-cobaltic chloride, [Co(NH3)6]C13.2... 

Although no direct evidence was found in the cobalt-N-hydroxyethylethyl-enediamine reaction that an oxygen-cobalt addition complex was formed, it seems reasonable to postulate that such an intermediate is present in the reaction. An oxygen-cobalt complex intermediate appears to afford the most logical method of explaining the evidence that the oxidation of cobalt (II) to cobalt (III) occurs in conjunction with the oxidative cleavage of the carbon-carbon bond of the hydroxyethyl group and the formation of ethylenediamine. 

In present work the influence of cobalt additive on catalytic properties of CuH-ZSM-5 zeolite, in both ethane oxidation and N2O decomposition, was studied. ESR spectroscopy was used for monitoring the change in either the valence or coordinative state of Cu isolated cations, located inside zeolitic channels, upon different treatments of the samples. 

A significant rise in the thermostability of bi-cationic sample also gives an indirect evidence of intimate interaction between two components in the zeolitic matrix. The ESR data (Fig. 3) demonstrates a big difference in local topography of isolated Cu " ions in two samples calcined at 750°C. The presence of cobalt additive preserves the sites with the most coordinatively unsaturated square-planar Cu " ions from high-temperature destruction. 

In recent publications there are contradictory points of view on the basis of unusual activity of CuH-ZSM-5 in both total oxidation of hydrocarbons and NO decomposition [3, 6, 8 - 11, 19, 20]. In our earlier work the decisive role of the low-coordinated square-planar Cu cations in alkane oxidation was demonstrated [11, 12, 14]. In our opinion, the results obtained agree well with these data the preservation of high catalytic activity of Co/CuH-ZSM-S/ gQO correlates well with conservation of just these the most unsaturated sites in Co/Cu-ZSM-S/ g. The physical mechanism of the stabilizing influence of cobalt additive on the conservation of Cu local topography in ZSM-5 matrix is unclear now. The migration of cobalt ions into zeolitic channels with formation of some kind of bi-cationic structures can not be excluded. 

Cobalt addition 2.5 ml of cobalt solution is added per liter of sample. 

Use Ceramics, pigments, glazes, in plating baths for cobalt, additive to soils, catalyst, paint and ink drier, storage batteries. 

The inhibition of chemisorption and methanol synthesis by cobalt addition to Cu/Zn0/Al203 catalysts occurs by a similar mechanism in which copper crystallites are covered by a cobalt-containing, oxidic monolayer. 

Investigations of F. Skaupy and co-workers at the Osram Studiengeselbchaft with iron, nickel, or cobalt additions to tungsten carbide were the basis for a patent about production of cemented carbides. 

With one equivalent of [(trpn) Co (H20)2] +, a complex is formed with AMP in which both emionic oxygens are coordinated to cobalt addition of the second equivalent is thought to form (234) transiently, with subsequent expulsion of adenosine affording the observed products. By heating at neutral pH in the presence of Mn2+ ions at temperatures above 50° C, ATP can be used to phosphorylate the hydroxy groups of serine and tyrosine non-enzymatically. Calcium ions can substitute for Mn + ions, albeit less effectively, but Mg + ions are ineffective. The reaction can be used to prepare radiolabelled phosphoserine - or phosphotyrosine-containing peptides. 

The alkyl-cobalt addition-elimination (cobalt group transfer) sequence has been used by Baldwin and Li during the enantiospecific synthesis of (-)-a-kainic acid (58a) and (-)-a-allokainic acid (58b). These reactions proceed via the carbon-centered... 

Mitrovic, S.M., Femandez-Amandi, M., McKenzie, L., Furey, A., and James, K.J., Effects of selenium, iron and cobalt addition to growth and yessotoxin production of the toxic marine dinoflagellate Protoceratium reticulatum in culture, J. Exp. Mar. Biol. EcoL, 313, 337, 2004. 

The sintered nickel substrate for the cathode is similar to that used for Ni-Cd and Ni-MH cell constructions. The nickel active materials are loaded into the sinter plate using either an aqueous (Bellcore) or alcoholic-based (Air Force or Pickett) electrochemical impregnation process. A 5-10% cobalt additive is deposited with nickel hydroxide to improve charge acceptance. These electrodes have a significantly longer cycle life over the standard vacuum impregnated or pasted nickel electrodes used in commercial Ni-Cd cells. 

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