Nitric oxide reaction with chlorine

Gas phase third-order reactions are rarely encountered in engineering practice. Perhaps the best-known examples of third-order reactions are atomic recombination reactions in the presence of a third body in the gas phase and the reactions of nitric oxide with chlorine and oxygen (2NO T Cl2 -> 2NOC1 2NO + 02 -> 2N02). 

Nitrosyl chloride can be prepared by the reaction of nitric oxide with chlorine ... 

At low concentrations of chlorine, dimeric nitrosoalkanes free from chlorine are produced when alkanes are treated also with nitric oxide. Under these circumstances, molecular chlorine is first converted into atomic chlorine which attacks the alkane to form alkyl radicals and hydrogen chloride. The alkyl radicals, in turn, form nitrosoalkanes with nitric oxide. This reaction is most effectively carried out when the ultraviolet radiation is between 380 and 420 mp. [43, 56],... 

Bodenstein has, however, shown that the combination of nitric oxide and oxygen 2N0 + 02 = 2N02 is a homogeneous change which is kinetically of the third order, and the same appears to apply to the combination of nitric oxide with chlorine and with bromine f and to the reaction between nitric oxide and hydrogen. J 2NO + C12 = 2NOC1 2NO + Br2 = 2NOBr 2NO + H2 = N20+H20... 

Of the reactions of nitric oxide with the halogens, the one with chlorine has been most extensively studied. Apparently, this reaction was first reported by Gay Lussac shortly before the Battle of Waterloo. Although almost all the early work (prior to 1938) was interpreted in terms of a termolecular reaction to form nitrosyl chloride... 

Fig. 5-1. Reaction of chlorine with nitric oxide tf[CINO]/

The work by Ashmore and co-workers on the nitric oxide-chlorine system has already been mentioned in the context of reactions of nitric oxide with molecular halogens. It was first suggested in 1953 by Ashmore and Chanmugam10 that the second-order molecular mechanism for the thermal decomposition of nitrosyl chloride might be accompanied by a radical mechanism at higher temperatures, which they envisioned as... 

Nitrosyl chloride has been prepared by passing nitrogen dioxide through moist potassium chloride,1 by the reaction of nitric oxide with chlorine,2 from nitrosylsulfuric acid and sodium chloride,3 and from nitrosylsulfuric acid and dry hydrogen chloride.4... 

DOT CLASSIFICATION 4.3 Label Dangerous When Wet, Poison SAFETY PROFILE A poison. Flammable when exposed to heat, flame, or oxidizing materials. Ignites when heated in chlorine, bromine, or iodine vapors. Incandescent reaction with nitric acid. Reacts with water to evolve flammable phosphine gas. When heated to decomposition it emits toxic fumes of POx and phosphine. See also MAGNESIUM and PHOSPHIDES. 

The gas-phase reaction of nitric oxide with chlorine has received a great deal of attention. Very often it has been studied concurrently with its reverse, the decomposition of nitrosyl chloride, viz. 

Nitrosyl chloride can be obtained by direct combination of chlorine with nitric oxide, by the reaction of NOHSO4 or NaNOj with HCl, or as a by-product in the preparation of KNOs from KCl and NO2, in which KCl is moistened with 2.4% water. Nitrosyl bromide is usually prepared by direct combination of bromine nuth nitric oxide. Nitrosyl chloride and nitrosyl bromide can be prepared by reacting the appropriate potassium halide with nitrogen dioxide at room temperature. The reaction rate increases with increased size of the halide, and NOCl and NOBr can be obtained in a reasonable length of time by powdering the halide salt before adding NO. ... 

The conversion of a wide variety of P, S, and N organic compounds over H-mordenite and HZSM-5 catalysts has been described. The reaction of nitric oxide and chlorine near to equilibrium over H-mordenite was studied by use of a pressure-jump method. The preparation of aliphatic amines from the reaction of Ci—C3 alcohols and ethers with ammonia over HZSM-5, HZSM-11, and HZSM-21 has been described. The proportion of secondary and tertiary amines decreased as the size of alcohol or ether reactant increased. Chang and Silvestri showed that methanethiol is converted over HZSM-5 to hydrocarbons in a broadly similar way to methanol. However, a higher temperature (755 K) is required and even so 27.2 % total carbon remains unconverted as (CH3)2S. Propane is the major paraffin and the aromatics are largely C9. 

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