Cobalt carbon oxide

Whereas finely divided cobalt is pyrophoric, the metal in massive form is not readily attacked by air or water or temperatures below approximately 300°C. Above 300°C, cobalt is oxidized by air. Cobalt combines readily with the halogens to form haUdes and with most of the other nonmetals when heated or in the molten state. Although it does not combine direcdy with nitrogen, cobalt decomposes ammonia at elevated temperatures to form a nitride, and reacts with carbon monoxide above 225°C to form the carbide C02C. Cobalt forms intermetallic compounds with many metals, such as Al, Cr, Mo,... 

Cobalt metal is significantly less reactive than iron and exhibits limited reactivity with molecular oxygen in air at room temperature. Upon heating, the black, mixed valence cobalt oxide [1308-06-17, Co O, forms at temperatures above 900°C the oHve green simple cobalt(II) oxide [1307-96-6] CoO, is obtained. Cobalt metal reacts with carbon dioxide at temperatures greater than 700°C to give cobalt(II) oxide and carbon monoxide. 

Cobalt(II) acetylacetonate [14024-48-7] cobalt(II) ethyUiexanoate [136-52-7] cobalt(II) oleate [14666-94-5] cobalt(II) linoleate [14666-96-7] cobalt(II) formate [6424-20-0], and cobalt(II) resinate can be produced by metathesis reaction of cobalt salt solutions and the sodium salt of the organic acid, by oxidation of cobalt metal in the presence of the acid, and by neutralization of the acid using cobalt carbonate or cobalt hydroxide. 

Chrornium—cobalt—alurninum oxide [68187-11-1]—Cl Pigment Blue 36, Cl No. 77343. A blue—green pigment obtained by calcining a mixture of chromium oxide, cobalt carbonate, and aluminum oxide. It may contain small amounts (<1% each) of oxides of barium, boron, siUcon, and nickel. 

In another case, cobalt(II) oxide can be prepared by heating the carbonate in the absence of air. ni2+ O2- o2-... 

A procedure involving catalytic oxidation of sulphones has also been developed218. In this case the sulphone is mixed with sodium carbonate and cobalt(II) oxide and the mixture is burned in a stream of oxygen. This method works very well for nitrogen-containing sulphones and requires no expensive equipment. 

Cobalt metal, oxides, carbonates, sulphides as powders It... 

Niu, S., Hall, M. B., 1997, Comparison of Hartree-Fock, Density Functional, Mpller-Plesset Perturbation, Coupled Cluster, and Configuration Interaction Methods for the Migratory Insertion of Nitric Oxide into a Cobalt-Carbon Bond , J. Phys. Chem. A, 101, 1360. 

Kuan-Xin, H., et ah, Electrodeposition of nickel and cobalt mixed oxide/carbon nanotube thin films and their charge storage properties. Journal of The Electrochemical Society, 2006. 153(8) p. A1568-A1574. 

The cobalt carbonate basic salt is the commercially-used cobalt carbonate. It is used primarily for manufacturing cobalt pigments. It also is used to prepare cobalt(II) oxide and other cobalt salts. 

Cobalt(ll) oxide is prepared by heating cobalt(lI) carbonate, C0CO3, cobalt(lll) oxide, C02O3 or tricobalt tetroxide, C03O4, at high temperatures in a neutral or slightly reducing atmosphere ... 

Reactions with alkali hydroxide yield cobalt(II) hydroxide. Cobalt(II) oxide is readily reduced by hydrogen, carbon or carbon monoxide to cobalt ... 

Cobalt(II) suhate is prepared by dissolving cobalt(II) oxide, hydroxide or carbonate in dilute suhuric acid, followed by crystaUization ... 

Tricobalt tetroxide is obtained when cobalt(ll) carbonate, cobalt(ll) or cobalt(III) oxide, or cobalt hydroxide oxide, CoO(OH) is heated in air at temperatures above 265°C. The temperature must not exceed 800°C (see decomposition temperature above). 

The substance is best prepared by dissolving cobaltous carbonate in the smallest possible quantity of hydrochloric acid, treating the cold solution with a mixture of concentrated aqueous ammonia and ammonium carbonate, and oxidising by means of a stream of air drawn through the liquid. When oxidation is complete ammonium chloride is added and the whole evaporated to a syrup dilute hydrochloric acid is added to remove carbon dioxide, and the liquid is saturated with ammonia gas to decompose any tetrammino-salt formed. On the addition of concentrated hydrochloric acid the salt crystallises out on cooling.6... 

Oxidation of cobalt(ll) to cobalt(lll) by oxygen in the presence of N-hydroxyethylethylenediamine and carbon produces large amounts of ethylenediamine. Other products are formaldehyde, formic acid, and ammonia. The sum of the moles of ethylenediamine and ammonia produced is equal to the total number of moles of cobalt(ll) oxidized. A steady-state concentration of Co(ll)-Co(lll) is established in which the ratio Co(lll)/ Co(ll) = 1.207. Thus cobalt ion behaves as a true catalyst for cleavage of the N-hydroxyethyl-ethylenediamine. The total amount of cobalt(ll) oxidized per unit time, X, was calculated from the derived equation X = 3.8 + 7.0 k2 T — 3.8e-2-2k 1, where k2 = 0.65 hr.—1 The observed rate of formation of ethylenediamine plus ammonia also follows this equation. It is proposed that the cobalt ion serves as a center where a superoxide ion [derived from oxidation of cobalt-(II) by oxygen] and the ligand are brought together for reaction. 

Noncatalytic oxidation to produce acetic acid can be carried out in the gas phase (350-400°C, 5-10 atm) or in the liquid phase (150-200°C). Liquid-phase catalytic oxidations are operated under similar mild conditions. Conditions for the oxidation of naphtha are usually more severe than those for n-butane, and the process gives more complex product mixtures.865-869 Cobalt and other transition-metal salts (Mn, Ni, Cr) are used as catalysts, although cobalt acetate is preferred. In the oxidation carried out in acetic acid solution at almost total conversion, carbon oxides, carboxylic acids and esters, and carbonyl compounds are the major byproducts. Acetic acid is produced in moderate yields (40-60%) and the economy of the process depends largely on the sale of the byproducts (propionic acid, 2-butanone). 

Twelve grains of cobalt carbonate are added in small portions to a suspension of 19.4g of sulfamic acid (see No. 92) in 30ml of water. The filtered solution is poured into a mixture of 18g of anhydrous ethylenediamine, 45ml of water, and 9.7g of sulfamic acid. After cooling in ice to room temperature, the mixture is oxidized in air for 3 hours as described in (1). 

Twelve grama of cobalt carbonate are dissolved in 45g of 67% hydriodie acid (No, 89), filtered, and added to 22g of pn and 22g of HI in 150ml of water The pink precipitate of cobalt (II) salt that forms is ignored vigorous oxidation with air for three hours rapidly converts it to a yellow product After filtration, the mother liquor is evaporated and two more batches of material are isolated the final volume is about 50mL... 

Forty grams of cobalt carbonate are combined with a mixture of concentrated hydrochloric acid and 40ml of water are used or a solution of 80g of cobalt chloride 6-hydrate in 106ml of hot water. The oxidized solution is... 

Cobaltous carbonate, C0CO1. is found almost pure in the mineral sphaerocobaltile in the Republic of Zaire and less extensively in Zambia. The pale-red anhydrous salt is obtained by reaction in solution of an alkaline carbonate and a cobaltous salt under a slight pressure of carbon dioxide (up 10 I atmosphere) and subsequent heating at 140 C The commercial salt is violet-red in color, partially hydrolyzed with an indeterminate composition. It is insoluble in H 0 and alcohol, bul dissolves easily in inorganic and organic acids, and is often used for the preparation of other salts. According to the thermal conditions it decomposes to the different types of oxides. 

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