The formation of aromatics from the gas-phase pyrolysis of stigmasterol: kinetics

The gas-phase pyrolysis of stigmasterol was investigated using molecular be am mass spectrometry to study the reaction pathways that lead to the format ion of aromatic compounds and to build an empirical kinetic model. We used multivariate data analysis to extract trends in the data and identify major product classes. Based on this analysis, we have developed a lumped kineti c model to describe the formation of intermediates and polynuclear aromatic hydrocarbons (PAHs). In our reaction scheme, stigmasterol is converted to highly substituted aliphatic ring compounds. These intermediate compounds a re then converted to PAHs. We determined kinetic parameters for the two ste p process and used them to produce response surface plots for the two produ ct classes as a function of temperature and gas-phase residence time. (C) 2 001 Elsevier Science Ltd. All rights reserved.