Catalytic pyrolysis of microcrystalline cellulose extracted from rice straw for high yield of hydrocarbon over alkali modified ZSM-5

To investigate the pyrolysis behaviour of microcrystalline cellulose (MCC) and obtain a high yield of hydrocarbon, MCC was extracted from rice straw. The modification of ZSM-5 by different molar concentrations (0.2 M, 0.4 M and 0.6 M) of NaOH solution was carried out. At the same time, pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) was performed without and with alkali-treated ZSM-5 maintaining biomass to catalyst ratio 0.25:1 at a fixed temperature of 500 degrees C. Results showed that the alkali treatment promoted aromatics and olefin by enhancing the mass transfer of molecules. A total hydrocarbon relative peak area of 87.71% was obtained when the ZSM-5 was treated with 0.4 M concentration of NaOH in comparison to other treated and parent ZSM-5. To assess the derivative conversion, thermogravimetric analysis (TGA) was studied at four effective heating rates of 5, 20, 35, and 50 K min(-1). Furthermore, to calculate the activation energy of MCC, Kissinger-Akahira-Sunose (KAS) method was studied. Results revealed activation energy for MCC increased from 137.98 to 157.18 kJ mol(-1) and decreased from 214.32 to 187.47 kJ mol(-1) for without and with catalyst, respectively. This research will have a potential to ensure high yield hydrocarbon production from cellulose as well as other lignocellulosic biomass.

Automated summary

This study investigated the pyrolysis behavior of microcrystalline cellulose extracted from rice straw, and the modification of ZSM-5 with different molar concentrations of NaOH solution. Results showed that alkali treatment promoted the production of aromatics and olefins, with changes in activation energy values.