Differential thermal analysis and thermogravimetry of ammonium perchlorate at pressures up to 51 ATM

Abstract

The thermal decomposition of pure ammonium perchlorate (AP)was investigated in various gaseous atmospheres at pressures up to 51 atm, using a technique of thermal analysis. It is concluded that the first and second stage decompositions of AP in an atmosphere of oxygen or nitrogen are appreciably accelerated as the pressure is increased. Platinum has a catalytic effect in the high-temperature decomposition and suppresses the sublimation of AP at high temperature ranges in helium atmosphere even at 1 atm. The reaction heat for the high-temperature decomposition of AP in the platinum cell was calculated from the peak temperatures of DTA curves at various pressures to be 77.9 kcal mol −1. The activation energies of the sublimation in helium at 1 atm and of the high-temperature decomposition in the platinum cell at various pressures of helium have also been obtained, giving similar values of 23–25 kcal mol −1.