SHOCK-TUBE STUDY OF HIGH-TEMPERATURE REACTIONS OF CYCLOPENTADIENE

The thermal decomposition of cyclopentadiene has been studied in the t emperature range 1260-1530 K behind reflected shocks. The total pressu re ranged from 1.5 to 2.3 bar. Resonance absorption was used to record the temporal concentration profiles of H atoms. This sensitive techni que allowed the study of the reaction systems under favorable conditio ns by applying very low initial concentrations (0.5-8 ppm). For cyclop entadiene decomposition R1, C5H6 --> C5H5-c + H, a rate expression of k(1) = 1.1 x 10(15) exp(-38760/T) s(-1) was deduced. In a separate ser ies of experiments the consumption by cyclopentadiene of H atoms, whic h had been generated by the thermal decay of ethyl iodide, was investi gated. A preliminary value of k(2) = 1.4 x 10(14) exp(-2739/T) cm(3) m ol(-1) s(-1) was deduced for the total rate of H-atom consumption by c yclopentadiene R2, C5H6 + H --> products.