Kinetic Analysis of Biomass and Comparison of its Chemical Compositions by Thermogravimetry, Wet and Experimental Furnace Methods

Abstract

Lignin, cellulose and hemicellulose are the major components of biomass. The chemical reactivities of the biomass are affected by the difference in chemical structures making the knowledge of their composition, essential to predict the efficiency of the biomass conversion process for utilizing bio-energy, which is of immense importance for successful commercialization of these processes and thus to gain energy security. Despite the presence of accurate and robust Wet Chemical methods, it is very difficult to implement these techniques commercially. Therefore, in this study the chemical composition of biomass has been determined by a simpler physical technique-Thermogravimetric Analysis (TG). The values obtained were correlated with chemical methods and it was found that TG predicted the holocellulose content with a relatively high accuracy while it underestimated the lignin content by a huge margin. The kinetic parameters of degradation of five biomass samples have also been reported in this study. This study also compared the mass loss profiles of the biomass in TG with their mass loss profiles in a furnace.

Thermogravimetric Kinetics of Catalytic Pyrolysis of Sugarcane Bagasse over Nickel-Cerium/HZSM-5 Catalyst

“…Moreover, the higher degradation rate of the second peak might be due to the high compositions of cellulose than hemicellulose in sugarcane bagasse. This is in good agreement with Goenka et al [25], stating that the presence of high cellulose compositions in biomass has higher degradation rates. Heating rates influence the thermal degradation rate of biomass that developed at different peak temperature points.…”

“…As a result, the produced coke could increase the activation energy. These are in a good agreement with the literature reported for higher activation energy from catalytic pyrolysis biomass than non-catalytic pyrolysis due to coke burning [25]. Moreover, this in line with DTG curve of catalytic pyrolysis in which developed a small peak in between 420 °C to 640 °C in Phase III at all heating rates as shown in Fig.…”

“…The variation in kinetic parameters is due to the degradation of biomass occurred at each heating rates. Thus, the orientation, position, and surface characteristics of molecules need to be in a potential well including heat and mass transfer characteristics that play a significant role in completing pyrolysis [25]. In addition, the activation energies obtained at multiple heating rates from Coats-Redfern method (model 5) are in line with the range of activation energy over conversion (10 -90 %) from Flynn-Wall-Ozawa method.…”

Thermal Characterization of Malaysian Biomass via Thermogravimetric Analysis

“…Conversely, coconut pulp has high HHV than other biomasses. Sugarcane Bagasse [29] 23.30 40.90 19.00 EFB [17] 21.60 23.70 29.20 Coconut Shell [34] 21.03 41.84 39.17 Coconut Pulp ---Rice Husk [29] 27.30 34.10 17.90 Saw Dust [29] 21.40 31.50 28.90…”

“…The results of TGA analyses are shown in Figure 1(a) and (b), which show the weight loss curves (TG) and derivative thermogravimetric (DTG) evolution profiles respectively, as a function of temperature, for all biomasses heated at a fixed heating rate (80 °C/min) and at a particle size of 0.3 ≤ dp1 < 0.5 mm. In general, the pyrolysis of biomass can be divided into three phases: drying and evaporation of light components (Phase I), devolatilization of hemicellulose and cellulose (Phase II), and decomposition of lignin (Phase III) [29,30]. Phase I occurred at the temperature below 150 °C, Phase II started to devolatize from 150 to 450 °C, and finally Phase III was attained at the temperature above 450 °C, which can be observed in Figure 1(a) and (b).…”