Nickel oxide decomposition

Methylsuccinic acid has been prepared by the pyrolysis of tartaric acid from 1,2-dibromopropane or allyl halides by the action of potassium cyanide followed by hydrolysis by reduction of itaconic, citraconic, and mesaconic acids by hydrolysis of ketovalerolactonecarboxylic acid by decarboxylation of 1,1,2-propane tricarboxylic acid by oxidation of /3-methylcyclo-hexanone by fusion of gamboge with alkali by hydrog. nation and condensation of sodium lactate over nickel oxide from acetoacetic ester by successive alkylation with a methyl halide and a monohaloacetic ester by hydrolysis of oi-methyl-o -oxalosuccinic ester or a-methyl-a -acetosuccinic ester by action of hot, concentrated potassium hydroxide upon methyl-succinaldehyde dioxime from the ammonium salt of a-methyl-butyric acid by oxidation with. hydrogen peroxide from /9-methyllevulinic acid by oxidation with dilute nitric acid or hypobromite from /J-methyladipic acid and from the decomposition products of glyceric acid and pyruvic acid. The method described above is a modification of that of Higginbotham and Lapworth. ... 

The catalytic activity of doped nickel oxide on the solid state decomposition of CsN3 decreased [714] in the sequence NiO(l% Li) > NiO > NiO(l% Cr) > uncatalyzed reaction. While these results are in qualitative accordance with the assumption that the additive provided electron traps, further observations, showing that ZnO (an rc-type semi-conductor) inhibited the reaction and that CdO (also an rc-type semi-conductor) catalyzed the reaction, were not consistent with this explanation. It was noted, however, that both NiO and CdO could be reduced by the product caesium metal, whereas ZnO is not, and that the reaction with NiO yielded caesium oxide, which is identified as the active catalyst. Detailed kinetic data for these rate processes are not available but the pattern of behaviour described clearly demonstrates that the interface reactions were more complicated than had been anticipated. 

In contact with fluorine, when it is cold, nickel oxide glows. It reacts violently with hydrogen peroxide (catalysis of its decomposition ). Finally, in contact with a mixture of hydrogen sulphide and air, it glows and causes this gaseous mixture to detonate. 

The effect of metal oxides in sensitising the thermal decomposition and explosion of the salt is in the order manganese dioxide > copper oxide > nickel oxide. 

With nickel/alumina catalysts (cf. 4 ) preparation by coprecipitation or by the decomposition of a high dispersion of nickel hydroxide on fresh alumina hydrogel, yields nickel aluminate exclusively. On the other hand, when, as in impregnation, larger particles of nickel compound are deposited, the calcination product is a mixture of nickel oxide and nickel aluminate. The proportion of nickel oxide increases when occlusion of the impregnation solution leads to a very nonuniform distribution (49). 

Fig. 24. Differential heats of adsorption of oxygen on nickel oxide [NiO(200)], as calculated from the experimental heats of decomposition of N20 at 30°C. Reprinted from (19) with permission.

Yang, C. C., Cutlip, M. B., and Bennett, C. 0. A study of nitrous oxide decomposition on nickel oxide by a dynamic method. Proc. of the Vth Congr. on Catal., Palm Beach, 1973. 

Ermakova and co-workers manipulated the Ni particle size to achieve large CF yields from methane decomposition. The Ni-based catalysts employed for the process were synthesized by impregnation of nickel oxide with a solution of the precursor of a textural promoter (silica, alumina, titanium dioxide, zirconium oxide and magnesia). The optimum particle size (10 0 nm) was obtained by varying the calcination temperature of NiO. The 90% Ni-10% silica catalyst was found to be the most effective catalyst with a total CF yield of 375 gcp/gcat- XRD studies by the same group on high loaded Ni-silica... 

RNi Raney nickel DNi catalyst prepared by the thermal decomposition of nickel formate HNi powder prepared by the hydrogenolysis of nickel oxide. 

Fig. 10. Percentage decomposition of N2O on a nickel oxide catalyst, with various additions of Li2O and InjOs, as a function of the temperature, according to Hauffe, Glang, and EngeU. (Composition of the reacting gas 15% N2O and 86% air flow rate 1200 cm. /hour.)...

Materials. The nickel oxide was prepared by decomposition of a very pure nickel hydroxide (25) in vacuo (p = 10"6 torr) at 250°C. (24,... 

It was verified by X-ray analysis that the second endothermal deflection in the thermal curve is the result of decomposition of the silicate structure (appearance of nickel oxide reflections). 

On comparing reducibility and the results of differential thermal analysis, it can be seen that the order of difficulty with which the preparations are reduced is the same as the order of difficulty with which they are decomposed. One might therefore expect the decomposition of hydrosilicate into nickel oxide, silica, and water to determine the velocity of the reduction... 

Various active nickel catalysts obtained not via reduction of nickel oxide with hydrogen have been described in the literature. Among these are the catalysts obtained by the decomposition of nickel carbonyl 10 by thermal decomposition of nickel formate or oxalate 11 by treating Ni-Si alloy or, more commonly, Ni-Al alloy with caustic alkali (or with heated water or steam) (Raney Ni) 12 by reducing nickel salts with a more electropositive metal,13 particularly by zinc dust followed by activation with an alkali or acid (Urushibara Ni) 14-16 and by reducing nickel salts with sodium boro-hydride (Ni boride catalyst)17-19 or other reducing agents.20-24... 

The temperature required for the reduction of cobalt oxides to the metal appears to be somewhat higher than for the reduction of nickel oxide. The catalyst with a higher catalytic activity is obtained by reduction of cobalt hydroxide (or basic carbonate) than by reduction of the cobalt oxide obtained by calcination of cobalt nitrate, as compared in the decomposition of formic acid.91 Winans obtained good results by using a technical cobalt oxide activated by freshly calcined powdered calcium oxide in the hydrogenation of aniline at 280°C and an initial hydrogen pressure of 10 MPa (Section... 

Nickel Tetracarbonyl, Ni(CO)4, is obtained when carbon monoxide is passed over metallic nickel 3 in a finely divided condition, such as is obtained by the reduction of nickel oxide in hydrogen at 400° C., the best temperature for obtaining the carbonyl being about 30-50° C. The carbonyl is condensed in a cooled vessel. The reaction may be advantageously carried out under a pressure of 2-100 atmospheres of carbon monoxide, in which case the temperature may be raised even to 250° C. without fear of decomposition.4... 

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