Catalysts containing cobalt

The selectivity of the oxidation of 2,6-disubstituted phenols depends on the type of oxidizing agent. For example, with a series of cobalt-containing catalysts of the salcomine type, oxidation of 2,6-dimethylphenol produces three products the poly(phenylene oxide), the diphenoquinone, and... 

In this section, we discuss processes in which cobalt-containing catalysts are employed for a variety of applications such as the reductions of molecular oxygen, carbon dioxide, and halogenated organic compounds as well as the oxidation of hydrazine. 

The reappearance of Brdnsted acid sites has been observed for the high calcined nickel-molybdenum-alumina catalysts. The presence of a nickel aluminate phase has been concluded from the reflectance spectra. The second Lewis band (1612 cm l) has a very low intensity, in comparison with the cobalt containing catalysts of a same composition and after the same calcination conditions. 

Scheme 4 shows a platinum catalyst 1 containing such a bis-SPO bidentate ligand anion, designed for the hydroformylation of ethylene and of 1-heptene, and various other, similarly built, platinum catalysts. Catalyst 1 has an activity comparable to that of the commercial cobalt catalysts that were used at the time and displays a higher selectivity for linear products than the cobalt-containing catalysts (66). Like the latter, the platinum complex exhibits hydrogenation activity to give, in part, alcohols in addition to aldehydes and also produces alkanes (an undesired reaction that implies a loss of feedstock). The catalysts are also active for isomerization, as are the cobalt complexes, and for internal heptene hydroformylation (Table 1), with formation of 60% linear products. 

Calcination and Reduction of Co/Al Hydroxycarbonates. As found with the Co/Al clays, temperature programmed reduction studies revealed that pre-calcination in air was necessary to produce a metallic cobalt-containing catalyst at reasonable reduction temperatures ... 

In general, the catalysts contain varying quantities of the oxides of aluminum, potassium, calcium, magnesium, and silicon as promoters. Patents recommend adding sodium [243], beryllium [244], vanadium [245], uranium [246], or platinum [247]. Reference [248] describes cesium-containing catalysts. Catalysts patented by Lummus [249] and Ammonia Casale [250] contain cerium as additional promoter. ICI [251] has developed a cobalt-containing catalyst, as has Grande Paroisse [252]. 

Nasirov, F.A. Bi-functional nickel- or cobalt-containing catalyst-stabilizers for polybutadiene production and stabilization. Iranian Polym. J. 2003, 12, 111. 

Di-n-propylamine can be produced in industrial scale by the alkylation of ammonia with n-propanol on Ba(OH)2 modified Ni/Al203 catalyst [2], by the reductive amination of propionaldehyde over a cobalt-containing catalyst [3] or by the hydrogenation acrylonitrile in n-exane on Ni/Al203 catalyst [4,5]. However, only scare data is available about the alkylation of ammonia or i-butylamine with i-butanol [6-10]. Di-i-butylamine was prepared from i-butanol over alumina at 370-380 C with 28 % yield [7]. 20 wt% Co - 5 wt% Ni catalyst supported on alumina was used to prepare di-i-butylamine fi"om i-butanol and i-butylamine at 200 °C with a yield of 60. 6 [10]. Aliphatic mixed secondary amines prepared from a pimary amine and an alcohol were usually obtained on copper-containing catalysts at 190-200 C with 30-50 % yields [11-13]. 

The amount of adsorbed CO on Pt/Ce/Al203 is about six times of that adsorbed on Pt/Al203. The TPD spectrum of Pt/Ce/Al203 shows an additional desorption peak at about 200°C, as shown in Figure 1. The addition of ceria seems to stabilise the noble metal dispersion. The cobalt containing catalysts all give similar TPD spectra, as shown in Figure 1,... 

By using sodium haiides or sodium borate the hydrogenation of D-fructose could be carried out almost to the completion. These results are shown in Table 3. In these experiments upon using Raney-copper catalysts the highest selectivity of D-mannitol, 82.7 %, was obsen/ed over a cobalt containing catalysts in the presence of sodium borate. Even higher D-mannitol selectivity, i.e. 88.2, was observed over CPG supported copper catalyst in the presence of sodium borate. 

Oxidation of cyclohexene by polymeric cobalt-containing catalysts [132,133] has many significant features. In the presence of Co(AcAc)2 (AcAc = acetyl-acetonate) the process is characterized by an induction period, after which the rate rapidly reaches its highest value and decreases thereafter (Fig. 12-10, plot 1). 

Hydrogenation of olefins catalyzed by transition metal complexes dissolved in ionic liquid solvents have been reported using rhodium-, and ruthenium- and cobalt-containing catalysts. In these studies it was shown that hydrogenation rates where up to five times higher than the comparable reactions when carried out in propanone. The solubilities of the alkene reagents, TOFs, and product distributions where all strongly influenced by the nature of the anion in the ionic liquid solvent... 

Cobalt-containing catalysts (5) are used in the petroleum industry (hydroprocessing) and desulphurisation COMOX (3-5% C03O4, 14% M0O3, remainder z- AI2O3), and in the chemical industry for 0X0 synthesis and the production of TPA (terephthalic acid) and DMT (di-methylterephthalate) where cobalt acetate or cobalt naphtenate/octoate are used. Finally, cobalt-containing catalysts are also used during the Fischer Tropsch synthesis of fuels, oils and waxes from natural gas (GTL gas-to-liquid conversion). These catalysts also contain non-trivial amounts of precious metals (Pt,Ru,Rh,...). 

A. Recycling Cobalt Catalysts to Custom Smelter. Most of the large custom smelters are equipped to recycle cobalt containing catalysts Ni-Co catalysts are processed at nickel-cobalt custom smelters such as Sudbury (Xstrata) and Kokkola (OMG), while catalysts containing high values of precious metals are recycled at precious metals custom smelters such as Umicore s. 

Main suitable catalysts are nickel-based catalysts, titanates-based perovskite oxides, cobalt-containing catalysts. 

The polymerization of butadiene is exactly comparable to that of isoprene (Section 18.3.3). Similarly, butadiene may be polymerized by a variety of methods, the choice of which determines the microstructure of the resulting polymer (Table 18.3). In the case of polybutadiene, of course, 1,2- and 3,4-addition cannot be distinguished. As mentioned in Section 18.4.1, sodium-polymerized butadiene has been produced commercially (and may still be in the U.S.S.R.), but at the present time most large-scale processes are based on either co-ordination catalysts (particularly titanium tetraiodide- and cobalt-containing catalysts) or alkyllithium catalysts. These processes are operated similarly to... 

College of Chemical Engineering investigated fused iron catalysts containing cobalt oxide and found that the activity increased significantly. Work of ICI in UK was noticeable for cobalt containing catalysts, and patented the Fe-Co catalysts. 

Milt, V.G., Ulla, M.A., and Lombardo, E.A. Cobalt-containing catalysts for the high-temperature combustion of methane. Catal. Lett. 2000, 65, 67-73. 

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