Soot formation in shock-tube pyrolysis of pyridine and toluene-pyridine mixtures

Abstract

Soot formation in pyridine and toluene-pyridine mixtures diluted in argon was studied behind reflected shock waves using a laser beam attenuation technique, over the temperature range 1520–2495 K and pressure range 175–359 kPa. Pyridine on pyrolysis gave soot in a similar fashion to aliphatic rather than aromatic hydrocarbons, whereas it gave soot as much as did toluene alone when it was added to toluene. A shift in the bell-shaped soot yield-temperature plot to lower temperatures was also observed when pyridine was added to toluene. The difference in soot yield between toluene and pyridine pyrolysis emphasizes the importance of the first ring as well as that of the products after thermal decomposition of the parent fuel.