Comparative study of carbonization of hydrocarbons.: The 24/26 rule.

Comparative study of different types of carbonization of hydrocarbons, i.e., electric discharges, thermal pyrolysis and pyrolysis in flame is reported. On the basis of GC/MS experiments, it can be concluded that a large number of compounds, mainly polycyclic aromatic hydrocarbons (PAHs) were formed in each cases. Similar PAHs were formed independently of the starting material, i.e., hexane or naphthalene. The formation of PAHs was explained by the 24/26 rule, i.e., the molar mass of PAHs increases by C-2 or/and C2H2 unit incorporation, regularly. The GC/MS investigation reveals that the C-2 or/and C2H2 incorporation takes place in both odd and even series of carbon atom number of PAHs. Fullerene formation was, however, observed only in the case of high temperature process, i.e., electric discharges. (C) 1999 Elsevier Science Ltd. All rights reserved.