REACTIONS OF NO, AND

The catalytic reaction of NO and CO on single crystal substrates, under ultra-high vacuum conditions, has been extensively studied. Neglecting N2O formation and CO desorption, the Langmuir-Hinshelwood mechanism of the NO + CO reaction can be described by the following sequence of steps [16,17] ... 

A reaction of ozone provides an example of concentration effects. Ozone in the atmosphere near the Earth s surface is a serious pollutant that damages soft tissues such as the lungs. In major urban areas, smog alerts are issued whenever there are elevated concentrations of ozone in the lower atmosphere. Nitmgen oxide, another component of photochemical smog, is a colorless gas produced in a side reaction in automobile engines. One reaction that links these species is the reaction of NO and O3 to produce O2 and NO2 ... 

First, analyze the one-step mechanism CO -I- NO2 CO2 4-NO This process is analogous to the reaction of NO and O3 discussed in Section 15-1. In a simple one-step atom transfer, the reaction is first order in each of the starting materials and second order overall ... 

Figure 10.8. Temperature-programmed reaction of NO and CO on two surfaces of rhodium. The initially molecularly adsorbed NO dissociates entirely at relatively low temperatures, but NO does not desorb. Note the difference in selectivity and reactivity between the surfaces on Rh(lOO) most of the CO oxidizes to CO2 and the reaction already...

Zhao et al. [74] developed a kinetic model to analyze the removal of nitrogen oxides in a pulsed corona discharge in NO/N2 mixtures. They considered reactions of NO and N02 with N and O atoms and with excited N2(A3S) molecules. 

Peroxynitrite, a non-radical product, is formed by the reaction of NO and CV-and is highly toxic to cells. 

The Rate Constants (298 K) for the on and off Reactions of NO and CO with certain Water Soluble Metal Complexes in Aqueous Solution... 

FIGURE 3 7 Composition of aerosol from the reaction of NO, and toluene. Reprinted with permission from Schwartz. ... 

TABLE 3-9 Composition of Aerosol from the Reaction of NO, and Various Olefins... 

The study of the intra-phase mass transfer in SCR reactors has been addressed by combining the equations for the external field with the differential equations for diffusion and reaction of NO and N H 3 in the intra-porous region and by adopting the Wakao-Smith random pore model to describe the diffusion of NO and NH3 inside the pores [30, 44]. The solution of the model equations confirmed that steep reactant concentration gradients are present near the external catalyst surface under typical industrial conditions so that the internal catalyst effectiveness factor is low [27]. 

Nitrous acid is also produced [24] with the reaction of NO and OH however, this acid will be oxidized to NO2 or HNO3 finally. 

TABLE 7.1 Some Rate and Equilibrium Constants of Aqueous-Phase Reactions of NO and NOza... 

Free-Radical Chemistry Kinetic and Spectroscopic Studies of Reactions of NO, and S04 Radicals with Aromatic Compounds, Faraday Discuss., 100, 129-153 (1995). 

Explosive salts such as NaNO can be prepared by the reaction of NO and liquid ammonia solutions of alkali metals. The unstable free arid, HNO, is thought to be an intermediate in many redox reactions of nitrogen compounds. 

The noncatalytic reduction of nitric oxide by insitu formed char is considered one of the significant reactions which control nitric oxide emission and a detailed kinetic study was carried out. (2, 3, 4) The present authors demonstrated that this reaction proceeded even under an excess air condition and that the rate is enhanced by the coexisting oxygen up to 750°C. (.5,6) Besides the noncatalytic reaction, carbon monoxide may have a significant effect on nitric oxide reduction by char. (2.) Roberts et al.(8) reported that the gas phase reactions in the nitric oxide reduction play a minor role and that the absence of a major gas phase reaction of NO and coal nitrogen into N2 requires the participation of a surface which catalyzes reactions. Char is considered to... 

Figure 13 Angular distributions for N2 formed by recombination at Ag(l 1 1) ( ) [93], Cu(l 1 1) ( ) [86] and Ru(000 1) (dotted line) [95], Recombination of N2 during reaction of NO and H2 on Pd(l 1 0) [96, 127] follows a statistical P(0) = cos 0 distribution (outer circle) while the fits for Ag, Cu and Ru show a P(0) = cos" 0 distribution with n = 75, 28 and 7, respectively. In order to fit on the same scale the angular distributions have been normalised at 0 = 0 and need to be scaled by a factor of (n + 1) to compare the distributions directly.

Figure 26 Translational energy released into N2 formed by reaction of NO and H2 at a Pd(l 1 0) surface held at 600 K [127]. The solid line is a fit to a thermal translational energy release, giving T = 425 K.

Nitrogen sesquioxide, N2Og (Also called dinitrogen trioxide), is formed by equimolar reaction of NO and N02. This oxide is, in turn, in equilibrium with the quite unstable nitrous acid, HN02, in the presence of water ... 

In aqueous solution the reaction of NO and 02 is very complex37 but the overall reaction appears to be... 

In the solid, the square pyramidal ion has bent apical and linear basal NO groups. The linear-bent transition probably requires little energy and may well be involved in reactions of dinitrosyl intermediates in reactions such as that noted previously, leading to a hyponitrite complex, or in reactions of NO and CO, catalyzed by nitrosyl complexes, to give N20 and C02. 

A valuable feature of the mechanism is that all the elementary steps are well known in other systems. In particular, there is no necessity to add a new branching step to the hydrogen—oxygen scheme, and indeed, apart from (xxxvii), the radical reactions of NO and NO2 are all of the general... 

M. Inomata, A. Miyamoto. Y. Murakami, Mechanism of the reaction of NO and NH3 on vanadium oxide catalyst in the presence of oxygen under dilute gas condition, J. Catal. 62 140(1980). 

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