Oxides cobalt

Cobalt(ii) oxide, CoO, has been used in solar absorbers [66]. It can be prepared by the CVD of cobalt(ii) acetylacetonate dihydrate (Co(acac)2 2 H2O acac 6) at temperatures between 150 °C and 400 °C [67]. Cobalt(II) acetate can be converted into CoO at temperatures above 300°C [66]. The decomposition yields a polycrystalline material. 

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The alkalized zinc oxide—chromia process developed by SEHT was tested on a commercial scale between 1982 and 1987 in a renovated high pressure methanol synthesis plant in Italy. This plant produced 15,000 t/yr of methanol containing approximately 30% higher alcohols. A demonstration plant for the lEP copper—cobalt oxide process was built in China with a capacity of 670 t/yr, but other higher alcohol synthesis processes have been tested only at bench or pilot-plant scale (23). 

AHoys can be produced by the coreduction process, carried out at 1000°C with calcium, from the oxide mixture. For example, samarium oxide [12060-58-1] and cobalt oxide are coreduced to a SmCo [12017-68-4] powder, CaO then being removed. 

Many competitive programs to perfect a metallic anode for chlorine arose. In one, Dow Chemical concentrated on a coating based on cobalt oxide rather than precious metal oxides. This technology was patented (9,10) and developed to the semicommercial state, but the operating characteristics of the cobalt oxide coatings proved inferior to those of the platinum-group metal oxide. 

Other sohd cathode systems that have been widely investigated include those containing lithium cobalt oxide [12190-79-3] LiCo02 (51), vanadium pentoxide [1314-62-17, 20, and higher vanadium oxides, eg, 0 3 (52,53). 

The scale formed on unalloyed cobalt during exposure to air or oxygen at high temperature is double-layered. In the range of 300 to 900°C, the scale consists of a thin layer of the mixed cobalt oxide [1308-06-17, Co O, on the outside and a cobalt(Il) oxide [1307-96-6] CoO, layer next to the metal. Cobalt(Ill) oxide [1308-04-9] maybe formed at temperatures below 300°C. Above 900°C, Co O decomposes and both layers, although of... 

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. 

Adhesion of Enamel to Steel. Cobalt compounds are used both to color and to enhance adhesion of enamels to steel (55). Cobalt oxide is often incorporated into the ground frit at rates of 0.5—0.6 wt %, although levels from 0.2 to 3 wt % have been used. The frit is fired for ten minutes at 850°C to give a blue enamel that is later coated with a white cover coat. 

MiscelEneous. Small quantities of cobalt compounds are used in the production of electronic devices such as thermistors, varistors, piezoelectrics (qv), and solar collectors. Cobalt salts are useful indicators for humidity. The blue anhydrous form becomes pink (hydrated) on exposure to high humidity. Cobalt pyridine thiocyanate is a useful temperature indicating salt. A conductive paste for painting on ceramics and glass is composed of cobalt oxide (62). 

The sulphation of cobalt oxide, CoO, follows the parabolic law up to 700°C and above 850°C, proceeding by outward diffusion of cobalt and oxygen ions through a sulphate layer which is coherent up to about 700°C. The mechanism... 

Cobalt and compounds SPA Cobalt oxide Catalysts Eibres Paint Paper and pulp processing Tungsten carbide binder... 

Fire Hazards - Flash Point Not flammable Flammable Limits in Air (%) Not flammable Fire Extinguishing Agents Not pertinent Fire Extinguishing Agents Not To Be Used Not pertinent Special Hazards of Combustion Products Toxic cobalt oxide fumes form during fires Behavior in Fire No data Ignition Temperature Not pertinent Electrical Hazard Not pertinent Burning Rate Not pertinent. 

It is also important to point out that pure cobalt oxide, alone or finely dispersed in Si02 (i.e. Co-Si02, Co-Si02-l and Co-Si02-2 in Table 1), zeolite HY, fullerene (i.e. C q/C-,0 80/20) is at least as effective as the reduced oxides for the production of nanotubules in our experimental conditions. In fact, the catalysts studied in this work are also active if the hydrogenation step is not performed. This important point, is presently being investigated in our laboratory in order to elucidate the nature of the active catalyst (probably a metal carbide) for the production of nanotubules. 

In both processes the CO can be converted to CO2 by passing the gases and steam over an iron oxide or cobalt oxide catalyst at 400°C, thereby generating more hydrogen ... 

Kobalto-. cobaltous, cobalto-, cobalt(II). -chlorid, n. cobaltous chloride, cobalt(II) chloride, -cyanwasserstoff, m., -cyanwasser-stoffs ure, /. cobaltocyanic acid, -nitrat, n. cobaltous nitrate, cobalt(II) nitrate, -oxyd, n. cobaltous oxide, cobalt (II) oxide, -salz, n. cobaltous salt, cobalt(IJ) salt, -sulfat, n. cobaltous sulfate, cobalt(II) sulfate, -sulfid, n. cobaltous sulfide, cobalt (II) sulfide, -verbindung, /. cobaltous compound. cobalt(II) compound. 

Kobaltoxyd, n. cobalt oxide, specif, cobaltic oxide, cobalt(III) oxide, -hydrat, n. cobalt hydroxide, -oxydul, n. cobaltocobaltic oxide, cobalt(II,III) oxide. 

Kobaltoxydul, n. cobaltous oxide, cobalt (II) oxide, -oxyd, n. cobaltocobaltic oxide, co-balt(II,III) oxide, -verbindung,/, cobaltous compound, cobalt(II) oxide. 

Chromium compounds as catalysts, 188 Chromium oxide in catalytic converter, 62 Chromium oxide catalysts, 175-184 formation of active component, 176,177 of Cr-C bonds, 177, 178 propagation centers formation of, 175-178 number of, 197, 198 change in, 183, 184 reduction of active component, 177 Clear Air Act of 1970, 59, 62 Cobalt oxide in catalytic converter, 62 Cocatalysts, 138-141, 152-154 Competitive reactions, 37-43 Copper chromite, oxidation of CO over, 86-88... 

Corrosion products include iron oxide (Fe203), ferrosoferric oxide (Fe304), nickel oxide (NiO), cobalt oxide (CoO), and complex Fe, Ni, and Co oxides. Cobalt in particular may present a problem (as cobalt59, a naturally occurring isotope), and when present as a contaminant in nickel alloys (such as Inconel 800), may enhance the development of an outer-core radiation field (see Section 7.4.1). 

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