Comparative Kinetic and Pyrolytic Studies of d-Glucose Using Formulated Red Mud, Sand, and HZSM-5

Abstract

The catalytic pyrolysis of d-glucose (DG) was conducted using a thermogravimetric analyzer (TGA) and formulated red mud (FRM) as the catalyst to determine the kinetic parameters of DG decomposition in the presence of the catalyst. The FRM reduced the overall activation energy (45.58–87.35 KJ/mol) of DG conversion compared to sand (45.27–112.00 KJ/mol). The trend of the frequency factor (A) for the catalytic pyrolysis (first-order reaction: 78.1–1.14 × 108 s–1) and non-catalytic pyrolysis (first-order reaction: 7.10–2.08 × 107 s–1) of DG was different, which indicated different reaction mechanisms. Compared to the sand and HZSM-5 catalyst, the FRM altered the thermal decomposition profile of the DG and promoted its decomposition at lower reaction temperatures. The thermogravimetric analyses showed that at 260 °C, the FRM catalyst converted more DG (50% conversion) than the HZSM-5 (44% conversion) and sand (35% conversion), which was in agreement with its activation energy. Furthermore, the DG decomposition was studied in a fixed-bed reactor using catalytic and non-catalytic pyrolysis conditions. The FRM promoted the formation of low-molecular-weight compounds (acetic acid and formic acid, CO2, formaldehyde, and CO) and hindered the formation of furans. The HZSM-5 catalyst promoted the formation of furans.