Iron cobalt oxide

The pristine MCM-48 silica phase has been synthesized by standard procedures described elsewhere [1]. Wet impregnation technique was used (1.6 molar aqueous solutions of cobalt(II) nitrate (Co(N03)2 6H20) and iron(III) nitrate (Fe(N03)3-9H20) with a ratio of lCo 2Fe) to introduce cobalt iron oxides into the mesoporous MCM-48 molecular sieve. After impregnation the material was calcined at 575° C for 6 hours, followed by a calcination at 600° C for 72 hours (product A) or at 650° C for 72 hours (product B), respectively. 

Figure 1 X-ray diffractograms of the intercalated cobalt iron oxides A and B and pristine MCM-48 silica inset enlargement of the high-angel region of phase A and B.

Figure 3 Nitrogen adsorption/desorption isotherms (taken at 77 K) of the pristine MCM-48 silica phase and the cobalt iron oxide containing MCM-48 silica materials A (calcination at 600° C) and B (calcination at 650° C).

There are a large number of inorganic NPs that can be potentially used in the biomedical field among them, metallic NPs (MNPs) such as gold, cobalt, iron oxide, core-shell silica/gold and more recently silver have been studied. In addition, during the last few years, biological applications of carbon nanoparticles... 

Sleitif, A.K., and Kapatf, J.S. (2010) Understanding oxygen vacancy migration and clustering in barium strontium cobalt iron oxide. Solid State lonks,... 

Teraoka, T., Zhang, K.M., Okamoto, K., and Yamazoe, Y. Mixed ionic-electronic condnctivity of lanthanum strontium cobalt iron oxide (Lai cSr cCoi Fey03 ) perovskite-type oxides. Mater. Res. Bull. 1988, 23, 51-58. 

Cobalt iron oxide Cobalt zinc oxide Gellert green Rinmann s green Swedish green Zinc green... 

Oxides with group 2 elements (Mg) cobalt magnesium oxide. Oxides with group 3-11 elements (Cr, Fe, W) cobalt iron oxide cobalt tungstate. 

In a discussion of cobalt green. Field (1835) noted two kinds - a mixture of cobalt blue qq.v.) and chromic yellow, and another prepared directly from cobalt. Wifti ftie latter he stated that it consists of cobalt with the addition of oxide of iron or zinc presumably the use of iron oxides would form a cobalt iron oxide. However, the exact composition appears to be currently unknown. 

Cobalt group Chromium aluminium cobalt oxide Cobalt aluminium oxide Cobalt arsenate Cobalt arsenic oxide hydrate Cobalt chromate Cobalt hexacyanoferrate(II) Cobalt iron oxide Cobalt magnesium oxide Cobalt tin oxide Cobalt tungstate Cobalt zinc oxide Cobalt(III) oxide Erythrite Cobalt black Cobalt blue Cobalt violet... 

Adiponitrile undergoes the typical nitrile reactions, eg, hydrolysis to adipamide and adipic acid and alcoholysis to substituted amides and esters. The most important industrial reaction is the catalytic hydrogenation to hexamethylenediarnine. A variety of catalysts are used for this reduction including cobalt—nickel (46), cobalt manganese (47), cobalt boride (48), copper cobalt (49), and iron oxide (50), and Raney nickel (51). An extensive review on the hydrogenation of nitriles has been recendy pubUshed (10). 

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. 

Paint pigments do not change colors on appHcation. Other common colors are violet from cobalt(II) phosphate [18475-47-3] pink from cobalt and magnesium oxides, aureolin yellow from potassiuim cobalt(III) nitrite [13782-01-9], KCo(N02)4, and cerulean blue from cobalt staimate [6546-12-5]. Large quantities of cobalt are used at levels of a few ppm to decolori2e or whiten glass and ceramics. Iron oxide or titanium dioxide often impart a yellow tint to various domestic ware. The cobalt blue tends to neutrali2e the effect of the yellow. 

Metal oxides, sulfides, and hydrides form a transition between acid/base and metal catalysts. They catalyze hydrogenation/dehydro-genation as well as many of the reactions catalyzed by acids, such as cracking and isomerization. Their oxidation activity is related to the possibility of two valence states which allow oxygen to be released and reabsorbed alternately. Common examples are oxides of cobalt, iron, zinc, and chromium and hydrides of precious metals that can release hydrogen readily. Sulfide catalysts are more resistant than metals to the formation of coke deposits and to poisoning by sulfur compounds their main application is in hydrodesulfurization. 

Ammonia production from natural gas includes the following processes desulfurization of the feedstock primary and secondary reforming carbon monoxide shift conversion and removal of carbon dioxide, which can be used for urea manufacture methanation and ammonia synthesis. Catalysts used in the process may include cobalt, molybdenum, nickel, iron oxide/chromium oxide, copper oxide/zinc oxide, and iron. 

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 ... 

A detailed study of the dehydrogenation of 10.1 l-dihydro-5//-benz[6,/]azcpinc (47) over metal oxides at 550 C revealed that cobalt(II) oxide, iron(III) oxide and manganese(III) oxide are effective catalysts (yields 30-40%), but formation of 5//-dibenz[7),/]azepinc (48) is accompanied by ring contraction of the dihydro compound to 9-methylacridine and acridine in 3-20 % yield.111 In contrast, tin(IV) oxide, zinc(II) oxide. chromium(III) oxide, cerium(IV) oxide and magnesium oxide arc less-effective catalysts (7-14% yield) but provide pure 5H-dibenz[b,/]azepine. On the basis of these results, optimum conditions (83 88% selectivity 94-98 % yield) for the formation of the dibenzazepine are proposed which employ a K2CO,/ Mn203/Sn02/Mg0 catalyst (1 7 3 10) at 550 C. 

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). 

Cobalt ores are often found in association with copper(II) sulfide. Cobalt is a silver-gray metal and is used mainly for alloying with iron. Alnico steel, an alloy of iron, nickel, cobalt, and aluminum, is used to make permanent magnets such as those in loudspeakers. Cobalt steels are hard enough to be used as surgical steels, drill bits, and lathe tools. The color of cobalt glass is due to a blue pigment that forms when cobalt(II) oxide is heated with silica and alumina. 

When the temperature of a carbonate reservoir that is saturated with high-viscosity oil and water increases to 200° C or more, chemical reactions occur in the formation, resulting in the formation of considerable amounts of CO2. The generation of CO2 during thermal stimulation of a carbonate reservoir results from the dealkylation of aromatic hydrocarbons in the presence of water vapor, catalytic conversion of hydrocarbons by water vapor, and oxidation of organic materials. Clay material and metals of variable valence (e.g., nickel, cobalt, iron) in the carbonate rock can serve as the catalyst. An optimal amount of CO2 exists for which maximal oil recovery is achieved [1538]. The performance of a steamflooding process can be improved by the addition of CO2 or methane [1216]. 

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