Thermal Decomposition Kinetics of Kerosene-Based Rocket Propellants. 1. Comparison of RP-1 and RP-2

The decomposition kinetics of the kerosene-based rocket propellants RP-1 and RP-2 was studied. For RP-2, decomposition reactions were performed at 375, 400, 425, and 450 degrees C. For RP-1, decomposition reactions were only performed at 450 degrees C because we had previously studied decomposition at 375, 400, and 425 degrees C. All of the decomposition reactions were performed in stainless-steel ampule reactors. At each temperature, the extent of decomposition as a function of time was determined by analyzing the thermally stressed liquid phase by gas chromatography. These data were used to derive global pseudo-first-order rate constants that approximate the overall rate of decomposition for the fuel. For RP-2, the rate constants ranged from 1.33 x 10(-5) s(-1) at 375 degrees C to 5.47 x 10(-4) S-1 at 450 degrees C. The rate constants for the decomposition of RP-1 are not significantly different in that temperature range. One use of these rate constants is for the design and planning of physical property measurements at high temperatures. On the basis of the amount of time required for 1% of the sample to decompose (t(0.01)), we found that allowable instrument residence times ranged from 15 min at 375 degrees C to 0.3 min at 450 degrees C.