Nitronium perchlorate, decomposition

Nitronium salts are colourless, crystalline and very hygroscopic nitronium perchlorate and sulphate are unstable and liable to spontaneous decomposition, whereas nitronium tetrafluoroborate and other complex fluoro-salts are relatively stable. 

The decomposition of nitronium perchlorate between 70° and 112° C. has been reported by Cordes (2) to proceed to the gaseous products NO2, Cl2, C102, NO3CI, and 02. As a result of some screening experiments we were aware that at 65° C. in sealed tubes, nitrosonium perchlorate was a major decomposition product. We were also aware that dinitrogen tetroxide, at least in the liquid phase, would quantitatively convert nitronium perchlorate to nitrosonium perchlorate. Thus, a mechanism involving only gaseous products appeared unlikely. 

A study of the decomposition of NOCIO4 under conditions identical to this study gave the following results (1) nitrosonium perchlorate decomposes with no noticeable induction period, giving only the gaseous products, N02, C102, Cl2 and 02 nitronium perchlorate is reported as a... 

Nitronium perchlorate, as an ion complex may exist as a transitory intermediate, which may either revert to ions, sublime, or decompose. A similar mechanism has been proposed for the decomposition of ammonium perchlorate (3). 

The perchlorates used for propellants and explosives are ammonium perchlorate (AP NH4CIO4), nitronium perchlorate (NP N02C104), and potassium perchlorate (KP KCIO4). AP is the major crystalline oxidizer used for composite rocket propellants. The oxygen molecules produced by the decomposition act as an oxidizer when AP particles are mixed with a polymeric fuel component, for example,... 

Thepnal Decomposition. Workers at the Hebrew Univ, Israel found that the thermal decompn of nitrosyl perchlorate at 100-140° results in an equilibrium being established with nitryl perchlorate and the decompn prods of both compds (nitronium). N dioxide, Cl dioxide, and O were found to be the final decompn prods isolated (Ref 6)... 

Nitronium salts are colorless, crystalline, hygroscopic compounds. Nitto-nium perchlorate, sulfate, and hexafluoroiodate are unstable. The spontaneous decomposition (explosive nature) of the perchlorate was experienced by Ingold [60]. It is in all probability due to the equilibrium with the covalent unstable nitrate... 

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