Reduction of NO with NHj

Okazaki, T. Chinone, A. Kurosaki, Nippon Kagalai Kaishi, 1977, 1282 (in Japanese). 

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Fig. 4.39 The effect of alkali poisoning of MoO.—TiOj on the catalytic aaivity in the reduction of NO with NHj MoO, content 10 atomic %, reaction temperature, 523 K, 548 K, 0 573 K.

Li J, Chang H, Ma L, Hao 1, Yang RT. Low-temperature selective catalytic reduction of NO with NHj over metal oxide and zeolite catalysts—a review. Catal Today 2011 175 147-56. 

Sultana A, Nanba T, Sasaki M, Haneda M, Suzuki K, Hamada H. Selective catalytic reduction of NO with NHj over different copper exchanged zeolites in the presence of decane. Catal Today 2011 164 495-9. 

Kwak JH, Tonkyn RG, Kim DH, Szanyi J, Peden CHF. Excellent activity and selectivity of Cu-SSZ-13 in the selective catalytic reduction of NO with NHj. J Catal 2010 275 187-90. 

The butterfly nitride clusters are active with H2 in the production of NH, NH2-containing clusters, and eventually to NHj, and they may serve as models for the reduction of NO with H2 and CO. 

The correlation of a BET surface area loss with sulfur content of the SOj-exposed catalysts suggests that sulfur deposits poison or blocks the surface. A similar trend of decreasing activity and surface area with increasing sulfur content was also observed by Ham et al. [24] for the reduction of NO by NHj over a CuHM catalyst. 

Metal oxide catalysts are extensively employed in the chemical, petroleum and pollution control industries as oxidation catalysts (e.g., oxidation of methanol to formaldehyde, oxidation of o-xylene to phthalic anhydride, ammoxidation of propylene/propane to acrylonitrile, selective oxidation of HjS to elemental sulfur (SuperClaus) or SO2/SO3, selective catalytic reduction (SCR) of NO, with NHj, catalytic combustion of VOCs, etc.)- A special class of metal oxide catalysts consists of supported metal oxide catalysts, where an active phase (e.g., vanadium oxide) is deposited on a high surface area oxide support (e.g., alumina, titania, ziiconia, niobia, ceria, etc.). Supported metal oxide catalysts provide several advantages over bulk mixed metal oxide catalysts for fundamental studies since (1) the number of surface active sites can be controlled because the active metal oxide is 100% dispersed on the oxide support below monolayer coverage,... 

Ren L, Zhu L, Yang C, Chen Y, Sun Q, Zhang H, Li C, Nawaz F, Meng X, Xiao F-S. Designed copper-amine complex as an efficient template for one-pot synthesis of Cu-SSZ-13 zeolite with excellent activity for selective catalytic reduction of NO by NHj. ChemCommun 2011 47 9789-91. 

Moehida, L, Kawano, S., Hironaka, M., Yatsunami, S., Korai, Y., Matsumura, Y. and Yoshikawa, M., Reduction of NO at very low concentration in air with NHj at room temperature over a series of calcined pitch-based active carbon fibers, Chem. Lett., 1995, (5), 385 386. 

The rates of precipitation deposition are mapped today and allow a comparison to be made with the results of the forest decline inquiry. To get below the critical load limit for the acid input under the present conditions of reduced input of alkaline dust, it is necessary to reduce not only the S02-emission but also the emission of NO and NHj. The reduction of the nitrogen compounds is also necessary in view of a reduction of the possible eutrophication of terrestrial ecosystems, the nitrate load of the groundwater and surface waters, as well as a reduction of the ozone load. 

Other gases with significant anthropogenic sources contribute to acid rain (NO and SO ), the reduction of the ozone layer (chlorofluorocarbons), nutrient transport (NHj... 

Figure 11 shows an example of NOx removal by the PE-SCR process using Co-ZSM-5 catalyst with NHj addition at 150 C. NO was completely converted to NO with 36 J/L in the plasma reactor. Although most of NO was converted into NO in the plasma zone, outlet NOx of the Co-ZSM-5 catalyst was mostly NO due probably to the back reaction of NO NO over the catalysts. Similar trends were also reported in the PE-SCR process using NaY or BaY catalysts [124] and Pd/AIjO [121]. Proper mixing of NHj with NO further increased the overall NOx reduction over the catalyst. The Co-ZSM5 catalyst showed a stable activity without fonning aerosol. NH slip was less than 10 ppm. 

The interpretation of the observed paramagnetism of some yellow products of the reduction of [Mn(CN)6] with K in liquid NHj as evidence for Mn species is by no means unequivocal. 

The activity measurements are carried out to determine the rate of equimolar reduction as a function of temperature, reactant concentration and catalyst composition. The NO reduction with NHj is performed in a conventional fixed-bed, plug-flow reactor. A schematic diagram of the apparatus is shown in figure 2. 

The NOj ion is reduced only with difficulty, e.g., by A1 in NaOH, which gives NH3. In view of the problem of nitrate (and nitrite) pollution63 through the use of nitrogen fertilizers, many studies of their removal as NH3, NHJ, or N2 have been made, but no very practical method yet exists. A recent example of homogeneous reduction is that using ethanol, ethers, or carboxylic adds in sulfuric add to give ammonium sulfate.64... 

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