Thermo-physical properties of pretreated agricultural residues for bio-hydrogen production using thermo-gravimetric analysis

Abstract This study was conducted to investigate thermo-physical properties of pretreated agricultural residues, in order to facilitate its further processing and utilization in the bio-hydrogen production researches. Soybean stalk, sorghum stalk, cotton stalk, corn stover, and corncob were investigated by thermo-gravimetric analysis method. The decomposition kinetic parameters were determined by FWO, DAEM, and Kissinger methods at heating rates of 5, 10, 20, 30, and 40 °C min −1 . Those fibers all had three mass loss steps assigned to moisture evaporation, main component decomposition, and other organic matters. Thermal stability of the fibers were all up to 200 °C, the peak temperature range of the decomposition process was 317.7–335.2 °C, and the main thermal decomposition ended about 350 °C when the mass loss up to 60%. The results showed that the apparent activation energy of each fiber changed along with the conversion rate, the average E α for most of selected fibers was close to each other, from 189.1 to 200.0 kJ mol −1 , except corncob. Corncob had the lowest residue content and E α . Considering of the highest cumulative hydrogen yield of corncob, these findings allow developing a simplified approach to better understand the thermo-physical properties of agricultural residues in the process of bio-hydrogen production.