Pitches pyrolysis kinetics: non-isothermal heat treatments, experiments and model

The present study was focused on the modelling of experimental pitches evol ution data obtained under non-isothermal heat treatment. The model, previou sly proposed for isothermal heat treatment, was based on phenomenological b asic mechanisms as gas-liquid, liquid-liquid mass transfer and chemical rea ctions with respect to the gamma, beta and alpha -resins weight fractions a ssimilated to basic equivalent chemical species. It has been extended to no n-isothermal conditions and successfully applied to experimental data for A 240 petroleum pitch at four final temperature levels (673, 703, 723, 743 K) and eight heating rates (0.5, 1, 2, 3, 3.5, 4, 4.5, 5 K min(-1)). The iden tified kinetic parameters were found to be in agreement with values encount ered in literature for similar basic phenomena. This led to an accurate pre dictive tool intended for reactor design and optimisation taking into accou nt the whole heat treatment process including the non-isothermal step. (C) 2001 Elsevier Science Ltd. All rights reserved.