Nitric oxide decomposition

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. 

Possibly, cellular thiols may be oxidized by the inactive adduct of nitric oxide and oxygen to regenerate a nitrosothiol or related species with EDRF activity. Some of the inconsistent results observed in bioassay systems may be due to the secondary and nonenzymatic formation of a nitrosothiols or other species capable of regenerating nitric oxide, which are leached into perfusion cascades. Consequently, bioassay systems should not be the gold standard to distinguish whether nitric oxide is the EDRF, because secondary reactions of nitric oxide decomposition products may regenerate nitric oxide. 

Mei, D.H., Ge, Q.F., Neurock, M., Kieken, L., Lerou, J. First-principles-based kinetic Monte Carlo simulation of nitric oxide decomposition over Pt and Rh surfaces under lean-burn conditions. Mol. Phys. 2004,102, 361-9. 

Let us review first the state of the art concerning nitric oxide decomposition. In the last 10 years the search for NO decomposition catalysts sharply increased in an effort to comply with more severe regulations which reduce the allowed emission level of this contaminant. Particularly during the 1990s quite a few papers have been published concerning the use of different rare-earth-containing perovskites and K2NiF4-type mixed oxides. Ni, Cu and Co are the most commonly used transition metals. 

Measurement of the end products of nitric oxide decomposition involves the combined problems of determining (1) what the likely products are, (2) whether products are stable enough in biological systems to survive separation and analysis, and (3) developing and optimizing specific methods... 

M. Shelef "On the Mechanism of Nitric Oxide Decomposition over Cu-ZSM-5", Catal. Letters, 15, 305 (1992)... 

Nitric oxide decomposition and reduction by ammonia, propene or propane were carried out on H-ZSM-5, Cu " ion-exchanged X-type and ZSM-5 zeolites. 

Zhang Y, Flytzani-Stephanopoulos M. Hydrothermal stability of cerium modified Cu-ZSM-5 catalyst for nitric oxide decomposition. J Catal 1996 164 131 5. 

Pure nitroglycerin is a stable Hquid at temperate conditions. It decomposes above 60°C to form nitric oxides which in turn catalyze further decomposition. Moisture increases the rate of decomposition under these conditions. Double- and multibase propellants containing nitroglycerin have substantially shorter stabiHty Hves at 65 and 80°C than do single-base propellants. The decomposition of nitroglycerin proceeds as... 

C. Further warming to 65°C forms white iron sulfate monohydrate [17375-41 -6], FeSO H2O, which is stable to 300°C. Strong beating results in decomposition with loss of sulfur dioxide. Solutions of iron(II) sulfate reduce nitrate and nitrite to nitric oxide, whereupon the highly colored [Fe(H20) (N0)] ion is formed. This reaction is the basis of the brown ring text for the quaUtative deterrnination of nitrate or nitrite. 

At the high temperatures found in MHD combustors, nitrogen oxides, NO, are formed primarily by gas-phase reactions, rather than from fuel-bound nitrogen. The principal constituent is nitric oxide [10102-43-9] NO, and the amount formed is generally limited by kinetics. Equilibrium values are reached only at very high temperatures. NO decomposes as the gas cools, at a rate which decreases with temperature. If the combustion gas cools too rapidly after the MHD channel the NO has insufficient time to decompose and excessive amounts can be released to the atmosphere. Below about 1800 K there is essentially no thermal decomposition of NO. 

Thermal or photo-induced decompositions of dialkyl peroxides in the presence of suitable substrates yield various products. For example, with nitric oxides, alkyl nitrites or nitrates are formed and, with carbon monoxide, Z fZ-alkyl esters are obtained (44) ... 

Physical properties of hexachloroethane are Hsted in Table 11. Hexachloroethane is thermally cracked in the gaseous phase at 400—500°C to give tetrachloroethylene, carbon tetrachloride, and chlorine (140). The thermal decomposition may occur by means of radical-chain mechanism involving -C,C1 -C1, or CCl radicals. The decomposition is inhibited by traces of nitric oxide. Powdered 2inc reacts violentiy with hexachloroethane in alcohoHc solutions to give the metal chloride and tetrachloroethylene aluminum gives a less violent reaction (141). Hexachloroethane is unreactive with aqueous alkali and acid at moderate temperatures. However, when heated with soHd caustic above 200°C or with alcohoHc alkaHs at 100°C, decomposition to oxaHc acid takes place. 

Thermal Decomposition. The therm decompn was studied betw 380 and 430° and found to be homogeneous and apparently 1st order. The products were complex and included nitric oxide, methane, carbon monoxide, and w plus small amts of ethane, ethylene, and nitrous oxide (Ref 23)... 

T.M. Giir, and R.A. Huggins, Decomposition of Nitric Oxide on Zirconia in a Solid-state electrochemical cell, J. Electrochem. Soc. 126(6), 1067-1075 (1979). 

Y. Matsumoto, T. Onishi, and K. Tamam, Effects of Sulphur on a Palladium Surface on the Adsorption of Carbon Monoxide and the Adsorption and decomposition of nitric oxide, J.C.S. Faraday I 76, 1116-1121 (1980). 

Kieken LD, Neurock M, Mei DH. 2005. Screening by kinetic Monte Carlo simulation of Pt-Au(lOO) surfaces for the steady-state decomposition of nitric oxide in excess dioxygen. J Phys Chem B 109 2234-2244. 

Iwamoto, M., Yokoo, S., Sakai, K. el al. (1981) Catalytic decomposition of nitric oxide over copper(II)-exchanged Y-type zeolites, J. Chem. Soc. Faraday Trans., 77, 1629. 

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