Pyrolytic formation of polycyclic aromatic hydrocarbons from sesquiterpenes

The products of the pyrolysis of four sesquiterpenes, β-caryophyllene, α-cedrene, longifolene and valencene, have been examined. Pyrolysis was carried out at 300, 400 and 500 °C, the products determined by GC–MS and then examined for similarities and differences using multivariate data analysis. Analysis showed that longifolene was most resistant and caryophyllene least resistant to pyrolysis with cedrene and valencene occupying intermediate positions. While the compounds were largely unchanged at 300 °C, polycyclic aromatic hydrocarbons (PAHs) were major components of the pyrolysates at 400 and 500 °C. No less than nine of the 16 EPA priority pollutants were present in the pyrolysates at the higher temperatures.