Nitric oxide reduction ammonia formation

Its formation can be kept to a minimum by keeping the excess air supplied to combustion units to a minimum value for safe complete combustion [56]. Burner designs that produce a more diffuse flame front (large flame volume) achieve lower peak combustion temperatures, which helps to decrease the formation of nitric oxide. Injection of ammonia into the flue gas while it is still hot can decrease NOx concentrations down to 80-120 ppm, one-third to one-half that of uncontrolled discharges [64]. Measures for NO reduction during operation of fluid catalytic crackers have been evaluated in pilot scale reactors [65]. 

NOx Reduction Catalyst. One of the most promising catalysts for reducing nitric oxide is ruthenium (Figure 2). It is unusual in that it catalyzes the reduction of NO with a low selectivity to ammonia which, if present, can be reoxidized in the second bed of a dual-bed system. When it is exposed at high temperatures to an oxidizing environment, however, ruthenium is lost through the formation of the volatile tetroxide. 

We turn first to a discussion of the adsorption of neutral species relevant to aqueous NO reduction. These species are the reductant, H the ambient water (H O) molecules the intermediates, nitric oxide (NO) and nitrous oxide (N O) and the products, nitrogen (N ) and ammonia (NH ). We have used the Pd(lll) facet to model our metal substrate. Since Pd is an fee metal, the (111) facet is the lowest energy termination, requiring the breaking of the fewest bulk metal bonds for its formation. The adsorption energy is the energy of the reaction ... 

Huang Z, Zhu Z. Liu Z, Liu Q (2003) Formation and reaction of ammonium sulfate salts on V205/AC catalyst during selective catalytic reduction of nitric oxide by ammonia at low temperatures. Journal of Catalysis 214 213-219... 

Nitric acid, UNO 3, and the nitrates are familiar enough so that little space need he devoted to them. It will be recalled that the acid is an excellent oxidizing agent when hot and concentrated, dissolving many metals and metallic sulfides, the latter with the formation of sulfur or sulfate. The reduction products of nitrate in acid solution are almost always the nitrogen(II) or nitrogen(IV) oxides, but nitrate can be reduced to ammonia in basic solutions, using active metals (such as zinc or aluminum). 

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