Study of the early deactivation in pyrolysis of polymers in the presence of catalysts

摘要: Abstract In this work, the early degradation step of pyrolysis some polymers in presence certain catalysts has been studied using thermogravimetric analysis (TGA). Three commercial (PE, PP and EVA) three were (ZSM-5, MCM-41a, MCM-41b), MCM-41a catalyst selected for earlier steps process carried out catalysts. Several cycles heating–cooling performed a thermobalance, order to analyze influence first stages decomposition on activity more accessible active sites involved. way, behaviour polymer–catalyst mixtures (20% (w/w) catalyst) was compared with that observed corresponding thermal as well catalysts, single heating cycle. The results obtained clearly show existence an step. For system low steric hindrances such PE-MCM-41, causes noticeable decrease main (i.e., cracking chain). catalytic is lower higher restrictions, occurs EVA-MCM-41 process. However, case, loss acetoxi groups) decreased after one run, thus reflecting involved are mainly most ones.