SOME EFFECTS OF MOLECULAR-STRUCTURE OF SINGLE HYDROCARBONS ON SOOTINGTENDENCY

The tendency of various single-component hydrocarbons to release soot from a laminar diffusion flame was investigated using experimental res ults obtained by the authors and other investigators. The hydrocarbon compounds considered include alkanes, alkenes, alkynes, aromatics and polyaromatics. It was found that the structure of hydrocarbon molecule s is one of the principal factors governing their sooting tendency in laminar diffusion flames. The ring is by far the most important molecu lar or submolecular structure and fused cyclic molecules are the most prolific sooters. In the case of non-aromatic hydrocarbons, secondary structural influences that tend to increase the sooting tendency are t he length of the main chain or ring circumference (in terms of carbon atoms) and the number, position and length of side-chains.