Nitric oxide catalyst

The offgas from the oxidizer goes to an absorber where sulfuric acid circulates. The nitric oxide catalyst is recovered, and other reactions complete the oxidation of HCl and regenerate nitrosylsulfuric acid ... 

Conversion of Ammonia. Ammonia [7664 1-7] mixed with air and having an excess of oxygen, is passed over a platinum catalyst to form nitric oxide and water (eq. 10). The AH g = —226 kJ/mol of NH consumed (—54 kcal/mol). Heats of reaction have been derived from heats of... 

Hydroxylamine sulfate is produced by direct hydrogen reduction of nitric oxide over platinum catalyst in the presence of sulfuric acid. Only 0.9 kg ammonium sulfate is produced per kilogram of caprolactam, but at the expense of hydrogen consumption (11). A concentrated nitric oxide stream is obtained by catalytic oxidation of ammonia with oxygen. Steam is used as a diluent in order to avoid operating within the explosive limits for the system. The oxidation is followed by condensation of the steam. The net reaction is... 

G. Fisher and co-workers, "Mechanism of the Nitric Oxide—Carbon Monoxide—Oxygen Reaction Over a Single Crystal Rhodium Catalyst," in M. 

Alternatively, hydroxylammonium salts can be made either (a) by the electrolytic reduction of aqueous nitric acid between amalgamated lead electrodes in the presence of H2SO4/HCI, or (b) by the hydrogenation of nitric oxide in acid solutions over a Pl/charcoal catalyst ... 

The older process is called the lead chamber process. It uses a mixture of gaseous oxides of nitrogen—nitric oxide, NO, and nitrogen dioxide, N02—as the catalyst. This process has been in use and under development for over 200 years. It is named after the large room-like chambers lined with lead in which the gaseous reactions are carried out. The lead walls react with the acid and become coated with an inert protective coating of lead sulfate. 

Nitric acid, manufacture, 45, 232 Nitric oxide as catalyst, 227 reaction with oxygen, 26 solubility, 20 Nitrobenzene, 344 Nitrogen... 

A sophisticated quantitative analysis of experimental data was performed by Voltz et al. (96). Their experiment was performed over commercially available platinum catalysts on pellets and monoliths, with temperatures and gaseous compositions simulating exhaust gases. They found that carbon monoxide, propylene, and nitric oxide all exhibit strong poisoning effects on all kinetic rates. Their data can be fitted by equations of the form ... 

In this example the XZ intermediate compound corresponds to the 2 N02 term, and the catalyst nitric oxide is regenerated continuously. 

Freund s group at the Fritz Flaber Institute have put much emphasis on linking surface science studies with applied catalysts through replicating the latter with model systems without having to resort to the complexity of the real system. A system they have studied in detail is that of nitric oxide chemisorption at a palladium-alumina model catalyst, where they isolated different... 

Other metal oxide catalysts studied for the SCR-NH3 reaction include iron, copper, chromium and manganese oxides supported on various oxides, introduced into zeolite cavities or added to pillared-type clays. Copper catalysts and copper-nickel catalysts, in particular, show some advantages when NO—N02 mixtures are present in the feed and S02 is absent [31b], such as in the case of nitric acid plant tail emissions. The mechanism of NO reduction over copper- and manganese-based catalysts is different from that over vanadia—titania based catalysts. Scheme 1.1 reports the proposed mechanism of SCR-NH3 over Cu-alumina catalysts [31b],... 

The reactions that occur to auto-exhaust emissions when exposed to plasma include oxidation of HCs, carbon monoxide, and partially diesel PM also. Nitric oxide (NO) can be oxidized by plasma to N02. Plasma alone, due to its oxidizing character, is not a viable NO control method. However, combinations of plasma with catalysts, referred to as plasma-assisted catalysts or simply plasma catalysts , have been suggested for NO reduction. The plasma is believed to show potential to improve catalyst selectivity and removal efficiency. Current state-of-the-art plasma catalysts have efficiencies comparable to those of active DeNO systems, removing about 50% of NO at a fuel economy penalty of less than 5% [85],... 

Bogdanchikova, N., Meunier, F.C., Avalos-Borja, M. et al. (2002) On the nature of the silver phases of Ag/Al203 catalysts for reactions involving nitric oxide, Appl. Catal. B 36, 287. 

Frank, B., Emig, G. and Renken, A. (1998) Kinetics and mechanism of the reduction of nitric oxides by H, under lean-burn conditions on a Pt-Mo-Co/a-ARO, catalyst, Appl. Catal. B 19, 45. 

Oda, T., Kato, T., Takahashi, T. et al. (1998) Nitric oxide decomposition in air by using nonthermal plasma processing with additives and catalyst, IEEE Trans. Ind. Appl. 34, 268-72. 

The iron complex (23) adsorbed on graphite electrode surfaces is an active catalyst for the electroreduction of both nitrite and nitric oxide to yield NH2OH and NH3, as demonstrated by rotating ring-disk electrode voltammetry experiments.341... 

Effect of a Novel Nitric Oxide Calcination on the Catalytic Behavior of Silica-Supported Cobalt Catalysts during Fischer-Tropsch Synthesis, and Impact on Performance Parameters... 

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