Influence of ZSM-5 zeolite on the pyrolytic intermediates from the co-pyrolysis of pubescens and LDPE

The catalytic reforming of the pyrolytic intermediates from the co-pyrolysis of pubescens and LDPE over the parent and desilicated zeolite ZSM-5 (DeZSM-5) was investigated. The results showed that the parent HZSM-5 exhibited high aromatization activity in the co-pyrolysis, whereas DeZSM-5 exhibited high alkanisation activity. On the other hand, the total relative content of phenolic compounds in aqua obtained by co-pyrolysis catalyzed by both parent HZSM-5 and DeZSM-5 was rather high (60-65%) compared to the thermal co-pyrolysis (26.94%). From the analysis of NH3-TPD for ZSM-5, it might be proposed that the aromatization was favored mainly by strong acid sites and the alkanisation was favored chiefly by weak acid sites in catalyst ZSM-5. In addition, the formation of phenolic compounds was mainly related to the interactions between the intermediates from the co-pyrolysis over ZSM-5. (C) 2009 Elsevier Ltd. All rights reserved.