Thermal Decomposition of Some Tert-Butyl Compounds at Elevated Temperatures

Abstract

A single‐pulse shock tube has been used to study the kinetics of the thermal decomposition of tert‐butyl chloride, bromide, alcohol, and mercaptan. The results are compared with those obtained by earlier workers who used static reaction vessels at lower temperatures. The rate constants for the unimolecular elimination reactions are $$\begin{array}{cc}{k}_{{\mathrm{C}}_4{\mathrm{H}}_9\mathrm{Cl}}{\text{=10}}^{\text{13.9}}{e}^{\text{−46 200/RT}}& {\text{(750}}^{\circ }{\text{−950}}^{\circ }\mathrm{K}\mathrm{),}\\ k_{{\mathrm{C}}_4{\mathrm{H}}_9\mathrm{Br}}{\text{=10}}^{\text{13.5}}{e}^{\text{−41 500/RT}}& {\text{(700}}^{\circ }{\text{−900}}^{\circ }\mathrm{K}\mathrm{),}\\ k_{{\mathrm{C}}_4{\mathrm{H}}_9\mathrm{OH}}{\text{=10}}^{\text{13.4}}{e}^{\text{−61 600/RT}}& {\text{(1050}}^{\circ }{\text{−1300}}^{\circ }\mathrm{K}\mathrm{),}\\ k_{{\mathrm{C}}_4{\mathrm{H}}_9\mathrm{SH}}{\text{=10}}^{\text{13.3}}{e}^{\text{−55 000/RT}}& {\text{(950}}^{\circ }{\text{−1230}}^{\circ }\mathrm{K}\mathrm{).}\end{array}$$ The results for the chloride and the bromide are in good agreement with those of other workers. The slight discrepancies that are present indicate that in the present work, in the temperature range 700°—950°K, the true reaction temperature behind the reflected shock is 10°—25°K lower than that computed in the usual manner.