Catalytic co-pyrolysis of wet-torrefied bamboo sawdust and plastic over the zeolite H-ZSM-5: Synergistic effects and kinetics

In the present study, the hemicellulose from bamboo sawdust (BSD) was selectively removed in the form of xylose and acetic acid using the wet-torrefaction technique in presence of formic acid and NaCl as catalysts. The best torrefaction activity, with xylose yield 85% and complete removal of hemicellulose, was obtained with formic acid:BSD 1:1 and NaCI:BSD 3:1 w/w. The torrefied BSD (TBSD) was catalytically co-pyrolyzed with linear low-density polyethylene (LLDPE) over HZSM-5. The apparent activation energies (E-m) of catalytic pyrolysis (CP) of TBSD, and LLDPE were 187 and 147 kJ mol(-1), respectively, from Kissinger-Akahira-Sunose (KAS) model. Those of catalytic co-pyrolysis (CCP) of blends TBP3:1, TBP1:1 and TBP1:3 were 163, 135 and 133 kJ mol(-1), respectively. The CCP of TBP1:3 and TBP1:1 showed synergism between TBSD and LLDPE in terms of E m and TBP1:3 (TBSD: LLDPE 1:3 w/w) showed the highest synergism with the least E m . The CCP mechanism of samples with a higher fraction of TBSD was more complex, as depicted from Criado's master plot. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

In this study, hemicellulose was selectively removed from bamboo sawdust using wet-torrefaction technique with formic acid and NaCl as catalysts. The co-pyrolysis of torrefied bamboo sawdust and linear low-density polyethylene showed synergistic effects, with TBP1:3 (TBSD: LLDPE 1:3) exhibiting the highest synergy with the lowest Em value. The mechanism of samples with a higher fraction of torrefied bamboo sawdust during catalytic co-pyrolysis was found to be more complex.