Parametrization of a Modified Friedman Kinetic Method to Assess Vine Wood Pyrolysis Using Thermogravimetric Analysis

Common kinetic parameters were obtained for leached and non-leached samples of vine wood biomass. Both samples were considered to have different proportions of cellulose, hemicellulose, and lignin compositions as a result of the leaching process. The two samples were analyzed in terms of pyrolysis kinetic parameters using non-isothermal thermogravimetric analysis. Furthermore, the classic Friedman isoconversional method, a deconvolution procedure using the Fraser–Suzuki function, and a modified Friedman method from a previous study on the delay in conversion degree were satisfactorily applied. The observed difference when the deconvolution technique was applied suggests that the classic Friedman method is not adequate for studying the pyrolysis of individual vine wood biomass components. However, this issue was solved by studying the delay in conversion degree of both biomasses and calculating the kinetic parameters using the resulting information. This procedure was found to be useful for studying and comparing the kinetics of heterogeneous biomasses and has a sound scientific explanation, making this research a basis for future similar studies.

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Thermogravimetric Analysis of Glucose-Based and Fructose-Based Carbohydrates

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.805-806.265 ◽

2013 ◽

Vol 805-806 ◽

pp. 265-268 ◽

Cited By ~ 1

Author(s):

Fang Ming Cui ◽

Xiao Yuan Zhang ◽

Li Min Shang

Keyword(s):

Activation Energy ◽

Thermogravimetric Analysis ◽

Kinetic Parameters ◽

Degree Of Polymerization ◽

Experiment Data ◽

Pyrolysis Characteristics ◽

The Difference ◽

Kinetic Calculations

Thermogravimetric analysis (TGA) was employed to study the pyrolysis characteristics of four glucose-based and three fructose-based carbohydrates. Kinetic parameters were calculated based on the experiment data. The results indicated that the starting and maximal pyrolysis temperatures of the glucose-based carbohydrates were increased steadily as the rising of their degree of polymerization (DP). The fructose-based carbohydrates exhibited similar pyrolysis behaviors as the glucose-based carbohydrates, but the difference was smaller. Kinetic calculations revealed that the activation energy values of the glucose-based carbohydrates were higher than those of the fructose-based carbohydrates, indicating the glucose-based carbohydrates were more difficult to decompose than the fructose-based carbohydrates.

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Pyrolysis Kinetics of the Arid Land Biomass Halophyte Salicornia Bigelovii and Phoenix Dactylifera Using Thermogravimetric Analysis

Energies ◽

10.3390/en11092283 ◽

2018 ◽

Vol 11 (9) ◽

pp. 2283 ◽

Cited By ~ 3

Author(s):

Prosper Dzidzienyo ◽

Juan-Rodrigo Bastidas-Oyanedel ◽

Jens Schmidt

Keyword(s):

Thermogravimetric Analysis ◽

Kinetic Parameters ◽

Arid Regions ◽

Date Palm ◽

Arable Land ◽

Thermo Gravimetric Analysis ◽

Phoenix Dactylifera ◽

Reaction Rates ◽

Gravimetric Analysis ◽

Salicornia Bigelovii

Biomass availability in arid regions is challenging due to limited arable land and lack of fresh water. In this study, we focus on pyrolysis of two biomasses that are typically abundant agricultural biomasses in arid regions, focusing on understanding the reaction rates and Arrhenius kinetic parameters that describe the pyrolysis reactions of halophyte Salicornia bigelovii, date palm (Phoenix dactylifera) and co-pyrolysis biomass using thermo-gravimetric analysis under non-isothermal conditions. The mass loss data obtained from thermogravimetric analysis of S. bigelovii and date palm revealed the reaction rate peaked between 592 K and 612 K for P. dactylifera leaves and 588 K and 609 K for S. bigelovii at heating rates, 5 K/min, 10 K/min and 15 K/min during the active pyrolysis phase. The activation energy for S. bigelovii and P. dactylifera leaves during this active pyrolysis phase were estimated using the Kissinger method as 147.6 KJ/mol and 164.7 KJ/mol respectively with pre-exponential factors of 3.13 × 109/min and 9.55 × 1010/min for the respective biomasses. Other isoconversional models such as the Flynn-Wall-Ozawa were used to determine these kinetic parameters during other phases of the pyrolysis reaction and gave similar results.

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AN INNOVATE METHOD OF THERMOGRAVIMETRIC DATA ANALYSIS

IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA ◽

10.6060/ivkkt.20216403.6348 ◽

2021 ◽

Vol 64 (3) ◽

pp. 24-32

Author(s):

Mihail V. Mal’ko ◽

Sergej V. Vasilevich ◽

Andrey V. Mitrofanov ◽

Vadim E. Mizonov

Keyword(s):

Experimental Data ◽

Thermal Decomposition ◽

Thermogravimetric Analysis ◽

Kinetic Parameters ◽

Calculation Method ◽

Kinetic Calculation ◽

Pyrolysis Mechanism ◽

Total Mass Loss ◽

Thermogravimetric Data ◽

Heavy Tar

The objective of the study is to examine the Coats-Redfern approximation and to propose an innovative kinetic calculation method for the complex process of the heavy tar thermal decomposition under non-isothermal process. The thermal decomposition process was examined using the thermogravimetric analysis. There are several kinetic models proposed to analyze pyrolysis mechanism in terms of the formal reaction. In this manner, the kinetic parameters of the pyrolysis process can be evaluated based on total mass loss (thermogravimetric analysis –TGA). The TGA procedures can be conducted with isothermal or non-isothermal conditions, but the experimental data obtained according to this procedure have to be transformed into appropriate correlation. The obtained results have shown that the reaction takes place within temperature range of 540 K to 700 K and the inductive period of the process is about 224 min. Kinetic parameters were estimated with using of the conventional Coats-Redfern method. A new kinetic calculation method has been designed to provide a less laboriousness of identifications procedures compared with Coats-Redfern approximation and to take into account an induction time of the process. As the outcome of this study, it was shown that the kinetic parameters estimated with using of the proposed model-fitted method gives the more appropriate correlation in comparison with the conventional Coats-Redfern method. The proposed method uses the Coats-Redfern algorithm for evaluation of the reaction mechanism, but the value of the constant rate is defined directly from experimental data on the conversion rate.

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Kinetic Analysis of the Thermal Decomposition of Polymer-Bonded Explosive Based on PETN: Model-Fitting Method and Isoconversional Method

Advances in Materials Science and Engineering ◽

10.1155/2020/9260818 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12

Author(s):

Trung Toan Nguyen ◽

Duc Nhan Phan ◽

Van Thom Do ◽

Hoang Nam Nguyen

Keyword(s):

Thermal Decomposition ◽

Kinetic Parameters ◽

Model Fitting ◽

Isoconversional Method ◽

Isothermal Tg ◽

Decomposition Reactions ◽

Model Free ◽

Negative Effect ◽

Adverse Influence ◽

Vacuum Stability Test

This work investigates kinetics and thermal decomposition behaviors of pentaerythritol tetranitrate (PETN) and two polymer-bonded explosive (PBX) samples created from PETN (named as PBX-PN-85 and PBX-PP-85) using the vacuum stability test (VST) and thermogravimetry (TG/DTG) techniques. Both model-free (isoconversional) and model-fitting methods were applied to determine the kinetic parameters of the thermal decomposition. It was found that kinetic parameters obtained by the modified Kissinger–Akahira–Sunose method (using non-isothermal TG/DTG data) were close to those obtained by the isoconversional and model-fitting methods that use isothermal VST data. The activation energy values of thermal decomposition reactions were 125.6–137.1, 137.3–144.9, and 143.9–152.4 kJ·mol−1 for PBX-PN-85, PETN, and PBX-PP-85, respectively. The results demonstrate the negative effect of the nitrocellulose-based binder in reducing the thermal stability of single PETN, while the polystyrene-based binder seemingly shows no adverse influence on the thermal decomposition of PETN in our presented PBX compositions.

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Pyrolysis Kinetic Parameters of Omari Oil Shale Using Thermogravimetric Analysis

Energies ◽

10.3390/en13164060 ◽

2020 ◽

Vol 13 (16) ◽

pp. 4060

Author(s):

Ziad Abu El-Rub ◽

Joanna Kujawa ◽

Samer Al-Gharabli

Keyword(s):

Activation Energy ◽

Thermogravimetric Analysis ◽

Kinetic Parameters ◽

Oil Shale ◽

Arrhenius Plot ◽

Frequency Factor ◽

Coefficient Of Determination ◽

Assay Method ◽

Temperature Integral ◽

Integral Approximation

Oil shale is one of the alternative energies and fuel solutions in Jordan because of the scarcity of conventional sources, such as petroleum, coal, and gas. Oil from oil shale reservoirs can be produced commercially by pyrolysis technology. To optimize the process, mechanisms and rates of reactions need to be investigated. Omari oil shale formation in Jordan was selected as a case study, for which no kinetic models are available in the literature. Oil shale was analyzed using the Fischer assay method, proximate analysis (moisture, volatile, and ash), gross calorific value, elemental analysis (CHNS), and X-ray fluorescence (XRF) measurements. Non-isothermal thermogravimetric analysis was applied to study the kinetic parameters (activation energy and frequency factor) at four selected heating rates (5, 10, 15, and 20 °C/min). When oil shale was heated from room temperature to 1100 °C, the weight loss profile exhibited three different zones: drying (devolatilization), pyrolysis, and mineral decomposition. For each zone, the kinetic parameters were calculated using three selected methods: integral, temperature integral approximation, and direct Arrhenius plot. Furthermore, the activation energy in the pyrolysis zone was 112–116 kJ/mol, while the frequency factor was 2.0 × 107 − 1.5 × 109 min−1. Moreover, the heating rate has a directly proportional relationship with the rate constant at each zone. The three different methods gave comparable results for the kinetic parameters with a higher coefficient of determination (R2) for the integral and temperature integral approximation compared with the direct Arrhenius plot. The determined kinetic parameters for Omari formation can be employed in developing pyrolysis reactor models.

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