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

Abstract

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 °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.