Co-pyrolysis of petroleum coke and banana leaves biomass: Kinetics, reaction mechanism, and thermodynamic analysis.

Insights into thermal degradation behaviour, kinetics, reaction mechanism, possible synergism, and thermodynamic analysis of co-pyrolysis of carbonaceous materials are crucial for efficient design of co-pyrolysis reactor systems. Present study deals with comprehensive kinetics and thermodynamic investigation of co-pyrolysis of petroleum coke (PC) and banana leaves biomass (BLB) for realizing the co-pyrolysis potential. Thermogravimetric non-isothermal studies have been performed at 10, 20, and 30 °C/min heating rates. Synergistic effect between PC and BLB was determined by Devolatilization index (Di) and mass loss method. Kinetic parameters were estimated using seven model-free methods. Standard activation energy for PC + BLB blend from FWO, KAS, Starink, and Vyazovkin methods was ≈165 kJ/mol and that from Friedman and Vyazovkin advanced isoconversional methods was ≈171 kJ/mol. The frequency factor calculated for the blend from Kissinger method was found to be in the range of 106-1016s-1. Devolatilization index (Di) showed synergistic effect of blending. The data pertaining to co-pyrolysis was found to fit well with R2 (second order) and D3 (three dimensional) from Z(α) master plot. Thermodynamic parameters, viz. ΔH ≈ 163 kJ/mol and ΔG ≈ 151 kJ/mol were calculated to determine the feasibility and reactivity of the co-pyrolysis process. The results are expected to be useful in the design of petcoke and banana leaves biomass co-pyrolysis systems.

Pyrolysis of mustard oil residue: A kinetic and thermodynamic study.

Critical analysis of thermogravimetric data, characterization of the biomass, and kinetic and thermodynamic analyses are crucial in the design of efficient biomass pyrolysis systems. In this study, characterization, kinetic and thermodynamic analysis was performed for pyrolysis of mustard oil residue (MOR). Thermogravimetric analysis (TGA) with differential thermal analysis (DTA) was applied to study thermal decomposition behaviour of MOR at 10, 20, and 30 °C/min. FTIR and XRD analyses were used to characterize MOR. Average activation energy estimated from employed isoconversional methods was ≈155 kJ/mol. Variation in activation energy was found to be statistically insignificant as suggested by p-value of 0.992 by one-way ANOVA method. The pyrolytic temperature for MOR ranged from 234 to 417 °C. Reaction mechanism predicted as R3 (third order) and D3 (three dimensional). Thermodynamic parameters (ΔHα, ΔGα, and ΔSα) showed that endothermicity increased from 0.2 to 0.8 conversion and product had highest energy at 0.8 conversion.

Studies on individual pyrolysis and co-pyrolysis of corn cob and polyethylene: Thermal degradation behavior, possible synergism, kinetics, and thermodynamic analysis.

The knowledge on thermo-kinetics, synergistic effect, and reaction mechanism of pyrolysis/co-pyrolysis of biomass with plastics is crucial for designing efficient reactor system and subsequently the pyrolysis/co-pyrolysis process. The present work explores thermal response, kinetics, reaction mechanism and thermodynamic analysis of pyrolysis and co-pyrolysis of individual corn cob (CC) and polyethylene (PE), and their blend in the ratio of 3:1 (w/w). Thermogravimetric analysis (TGA) data was obtained under inert atmosphere at various heating rates of 10, 20, and 30 °C/min and synergistic effect in the co-pyrolysis of CC and PE is discussed. The obtained TGA data was processed using various model-free isoconversional methods like KAS, FWO, Friedman, Starink, and Vyazovkin for determination of kinetics of pyrolysis/co-pyrolysis process of CC and PE. Average activation energy for CC pyrolysis was estimated to be 240 ± 51.25 kJ/mol, 240 ± 51.51 kJ/mol, 237 ± 49.67 kJ/mol, and 245 ± 52.10 kJ/mol according to KAS, Starink, FWO, and Vyazovkin models, respectively. Statistical analysis showed that the variation in reported values of activation energy was not significantly different (p = 0.994). Similar statistically insignificant difference was also observed for pyrolysis of PE and co-pyrolysis of CC and PE. Results showed that co-pyrolysis (CC + PE) requires 10% less activation energy than pyrolysis of CC alone. For the co-pyrolysis process, the extent of synergistic effect was discussed by difference in mass loss (ΔW). Investigation also revealed that residue left for co-pyrolysis of CC and PE is 50% less than pyrolysis of CC alone showing synergistic effect during co-pyrolysis. Thermodynamic parameters were calculated to illustrate complex mechanism of the process. Third order reaction, 3D diffusion Jander, and Ginstling-Brounshtein (D4) models were found to be best fitted for CC pyrolysis, PE pyrolysis, and co-pyrolysis, respectively. Results obtained are expected to be useful in the design of corn cob and waste polyethylene co-pyrolysis systems.

Pyrolysis of banana leaves biomass: Physico-chemical characterization, thermal decomposition behavior, kinetic and thermodynamic analyses.

In the present work, non-isothermal thermogravimetric experiments were conducted at three heating rates, viz. 10, 20, and 30 °C/min to study the thermal degradation of banana leaves biomass, where the key objective was to determine the kinetic triplet (activation energy, pre-exponential variable, and reaction model) and thermodynamic parameters. The kinetic study was carried out using five model-free isoconversional methods, viz. Flynn-Wall-Ozawa, Kissinger-Akahira-Sunose, Starink, Friedman, and Kissinger. Results showed that average activation energy ranges between 70.75 and 92.12 kJ/mol for the studied isoconversional model-free methods. The average activation energy obtained by KAS (79.36 kJ/mol) was found to be in the proximity of that obtained by FWO (84.02 kJ/mol). Pre-exponential factor obtained from Kissinger method was found to vary from 107 to 1033 s-1. Master plot showed that data fits well with second order reaction model till 0.2 conversion and then follows third order reaction model from 0.2 to 0.5 conversion.