Copper-magnesium oxide catalyst

Cunningham et al (63) have studied the rate of hydrogenation of ethylene at 1 atm on a copper-magnesium oxide catalyst. They used flow reactors to study the reaction kinetics over both finely divided catalyst particles and spherical... 

Cunningham, Carberry, and Smith [AIChE J., 11 (636), 1965] have studied the catalytic hydrogenation of ethylene over a copper-magnesium oxide catalyst. 

Example 2-1 Wynkoop and Wilhelm studied the rate of hydrogenation of ethylene, using a copper-magnesium oxide catalyst, over restricted pressure and composition ranges. Their data may be interpreted with a first-order rate expression of the form r = (ki)pPH (A)... 

Salts of neodecanoic acid have been used in the preparation of supported catalysts, such as silver neodecanoate for the preparation of ethylene oxide catalysts (119), and the nickel soap in the preparation of a hydrogenation catalyst (120). Metal neodecanoates, such as magnesium, lead, calcium, and zinc, are used to improve the adherence of plasticized poly(vinyl butyral) sheet to safety glass in car windshields (121). Platinum complexes using neodecanoic acid have been studied for antitumor activity (122). Neodecanoic acid and its esters are used in cosmetics as emoUients, emulsifiers, and solubilizers (77,123,124). Zinc or copper salts of neoacids are used as preservatives for wood (125). 

Catalysts. Cupric oxide was prepared by thermal decomposition of reagent grade copper nitrate (Wako Pure Chem.Inc.Ltd.) at 400°C in air for 4 hrs. Magnesium oxide was commercially available reagent grade powder (Kanto Chemical Co.Ltd.). The oxides powders were pressed into tablets and crushed and 24-42 mesh granules were used as catalysts. 

In support of that explanation, X-ray analysis of the catalyst after use indicated the presence of MgO. Hence, the catalytically active phase was finely divided copper in intimate contact with magnesia, quasi as carrier. The same phenomenon was observed with the Zintl-phase alloys of silver and magnesium. Such catalysts were then deliberately prepared by coprecipitation of copper and silver oxides with magnesium hydroxide, followed by dehydration and reduction. Table I shows that these supported catalysts had the same activation energies as those formed by in situ decomposition of copper and silver alloys with magnesium. 

The deflagration of hydrazine perchlorate, both pure and with fuel and catalyst additives, has been investigated. Hydrazine perchlorate will deflagrate reproducibly if a few percent fuel is present. The deflagration process is catalyzed by copper chromite, potassium dichromate, and magnesium oxide. Deflagration rates have been measured photographically from 0.26 to 7.7 atm. A liquid layer was observed at the surface in these experiments. Vaporization rate measurements from 180°-235° C. have yielded the expression... 

Effects of Catalysts. It has been found that copper chromite, potassium dichromate, and magnesium oxide promote the deflagration of hydrazine perchlorate. Since none of these additives has any fuel content, they must be considered to be catalysts. The results of experiments with these additives are shown in Table IV. Experiments were performed both with pressed (p 1.9 grams/cc.) and tamped (p 1.1. grams/cc.) strands. 

Magnesium oxide exerts quite a different effect than do the above catalysts. Thus, less of it, 2%, is required to promote steady deflagration, but it is not capable of producing as spectacular a rate as copper chromite or potassium dichromate even in amounts as great as 10%. 

Explodes on contact with bromine trifluoride chlorine trifluoride fluorine hydrogen peroxide + catalysts acetylene + ethylene. Explodes when heated with calcium carbonate + magnesium 3,4-dichloronitrobenzene + catalysts vegetable oils + catalysts ethylene + nickel catalysts difluorodiazene (above 90°C) 2-nitroanisole (above 250°C/34 bar + 12% catalyst) copper(II) oxide nitryl fluoride (above 200°C) polycarbon mono fluoride (above 500°C). 

Methylation of phenol is carried out either in vapor phase or liquid phase. Catalysts employed have been magnesium oxide, mixtures of magnesium oxide and oxides of manganese, copper, titanium, etc. Temperatures have varied from 390° C to 420° C and pressures atmospheric or somewhat higher pressure. Of late, zeolite catalysts have proved to be more effective and eco-friendly. 

Pure iron(iii) oxide performs rather poorly as a WGS catalyst, due to rapid catalyst deactivation by sintering. Traditional iron catalysts typically consist of iron(iii) oxide (80-90% by mass), chromium(iii) oxide (8-10% by mass) and small amounts of other stabilisers and promoters such as copper(ii) oxide, aluminium oxide, alkali metals, zinc oxide and magnesium oxide. The small fraction of chromium(iii) oxide acts to prevent catalyst sintering, and also promotes the catalytic activity of iron. Catalyst deactivation is typically caused by poisons in the feedstock gases and by deposition of solids on the catalyst surface. 

LTFT iron catalysts are commonly prepared by precipitation techniques, with a typical composition of potassium oxide, copper, silica and iron (1 1 5 20 by mass). Before use in the LTFT process, the catalysts are prereduced with either hydrogen or a syngas mixture.HTFT catalysts can be formed from the fusion of magnetite with various promoters, typically potassium oxide and aluminium oxide or magnesium oxide. Similarly, HTFT catalysts require a pre-reduction with hydrogen at ca. 400 °C. 

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