Ammonium perchlorate activation energy

Because of the use of ammonium perchlorate as a soHd oxidizer for rocket propeUants, the thermal decomposition has been much studied (29—32). Three separate activation energies have been observed for AP decompositions an activation energy of 123.8 kJ/mol (29.6 kcal/mol) is found below 240°C of 79.1 kj/mol (18.9 kcal/mol) above 240°C and finally, of 307.1 kj/mol (73.4 kcal/mol) between 400—440°C (33,34). Below 300°C, the equation... 

According to Glasner and Makovky [13] the activation energy of decomposition of ammonium perchlorate is 31.0 kcal/mole in the temperature range 440-478°C. 

The activation energy of decomposition of both irradiated and unirradiated ammonium perchlorate in the orthorhombic form below 240°C is ca. 18.0 kcal/mole according to Freeman. This seems to indicate that irradiation of ammonium perchlorate does not change the decomposition mechanism but provides many more nucleation sites. 

Table II. Differences in free energy of activation values (AG, kcal mol for the interaction of chiral macrocyclic ligands with (R)- and (5)-1-(1-naphthyl) ethyl ammonium perchlorate as determined experimentally (NMR) and as calculated from empirical energy functions. ...

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