Effect of Pyrolysis Atmosphere on the Gasification of Waste Tire Char

The aim of the study is to assess the influence of the atmosphere during pyrolysis on the course of CO2 gasification of a tire waste char. Two approaches were used: the pyrolysis step was carried out in an inert atmosphere of argon (I) or in an atmosphere of carbon dioxide (II). The examinations were carried out in non-isothermal conditions using a Rubotherm DynTherm thermobalance in the temperature range of 20–1100 °C and three heating rates: 5, 10 and 15 K/min. Based on the results of the gasification examinations, the TG (Thermogravimetry) and DTG (Derivative Thermogravimetry) curves were developed and the kinetic parameters were calculated using the KAS (Kissinger-Akahira-Sunose) and FWO (Flynn-Wall-Ozawa) methods. Additionally, the CO2 gasification of tire chars reaction order (n), was evaluated, and the kinetic parameters were calculated with the use of Coats and Redfern method. Tire waste char obtained in an argon atmosphere was characterized by lower reactivity, which was reflected in shift of conversion and DTG curves to higher temperatures and higher mean values of activation energy. A variability of activation energy values with the progress of the reaction was observed. For char obtained in an argon atmosphere, the activation energy varied in the range of 191.1–277.2 kJ/mol and, for a char obtained in an atmosphere of CO2, in the range of 148.0–284.8 kJ/mol. The highest activation energy values were observed at the beginning of the gasification process and the lowest for the conversion degree 0.5–0.7.

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Calculation of Kinetic Parameters of the Thermal Decomposition of Residual Waste of Coniferous Species: Cedrus Deodara

Acta Technologica Agriculturae ◽

10.2478/ata-2018-0014 ◽

2018 ◽

Vol 21 (2) ◽

pp. 75-80 ◽

Cited By ~ 3

Author(s):

Alok Dhaundiyal ◽

Muammel M. Hanon

Keyword(s):

Activation Energy ◽

Thermal Decomposition ◽

Kinetic Parameters ◽

Frequency Factor ◽

Inert Atmosphere ◽

Kissinger Method ◽

Heating Rates ◽

Cedrus Deodara ◽

Coniferous Species ◽

Competitive Reactions

Abstract This paper deals with pyrolysis decomposition of Cedrus deodara leaves with the help of thermogravimetric analysis (TGA). Experiments are performed in the presence of inert atmosphere of nitrogen. Experiments are conducted at three different heating rates of 5 °C∙min-1, 10 °C∙min-1 and 15 °C∙min-1 within temperature range of 35 °C to 700 °C. Arrhenius parameters such as activation energy and frequency factor are estimated by Flynn Wall and Ozawa (FWO), Kissinger-Akahira-Sonuse (KAS) and Kissinger. The activation energy and frequency factor calculated by using Kissinger method are 67.63 kJ∙mol-1 and 15.06 . 104 min-1 respectively; whereas the averaged values of the same parameters through FWO and KAS methods are 89.59 kJ∙mol-1 and 84.748 kJ∙mol-1, 17.27 . 108 min-1 and 62.13 . 107 min-1 respectively. Results obtained through Kissinger method represent the actual values of kinetic parameters. Conversely, FWO and KAS methods reflect the apparent values of kinetic parameters, as they are highly influenced by the overlapping of competitive reactions occur during pyrolysis.

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Eriobotrya japonica Lindl. Kernels: Kinetics of Thermal Degradation under Inert Atmosphere Using Model-Free and Fitting Methods

Biointerface Research in Applied Chemistry ◽

10.33263/briac114.1135711379 ◽

2020 ◽

Vol 11 (4) ◽

pp. 11357-11379

Keyword(s):

Activation Energy ◽

Thermal Degradation ◽

Mass Loss ◽

Kinetic Parameters ◽

Inert Atmosphere ◽

Eriobotrya Japonica ◽

Heating Rates ◽

Noticeable Effect ◽

Exponential Factor ◽

Model Free

A kinetic study of the pyrolysis process of raw Eriobotrya japonica Lindl. Kernels (RLK) was investigated using a thermogravimetric analyzer. The weight loss was measured in a nitrogen atmosphere. The samples were heated over a range of temperature from 298 K to 873 K with four different heating rates of 5, 10, 15, 20 K min-1. Mass loss (TGA) and derivative mass loss (DTG) measurements indicate that the increase in heating rate has no noticeable effect on the thermal degradation of the RLK. The results obtained from the thermal decomposition process indicate that there are three main stages such as dehydration, active, and passive pyrolysis. TGA curves indicate that active pyrolysis of RLK is between 160 and 450 °C. In this interval, a shoulder followed by a peak exists on the DTG plots. The shoulder corresponds to the decomposition of hemicelluloses, the first peak to that of cellulose. Lignin decomposes through all temperature range. The kinetic parameters such as activation energy and pre-exponential factor were obtained for two degradation steps by isoconversional model-free methods proposed by FWO, KAS, Kissinger, Tang, MKN, and FR, with degradation mode being: f(α)=(1-α)n with n = 1 for FR and g(α)=-Ln(1- α) for the other methods. The activation energy and pre-exponential factor obtained by the Kissinger method are 173 kJ/mol and 1.9×1016 min-1. While for free model methods, the average kinetic parameters calculated are 172-248 kJ.mol-1 and 5,30×1020 for integral methods (FWO, KAS, Tang and MKN) and 190-271 kJ.mol-1 and 1.77×1022 min-1 for differential Fr method. The activation energy decreases in the final stages of the process. The energy required for hemicellulose degradation is lower than that of cellulose. The most probable reaction functions have thus been determined for these two stages by Coats-Redfern and Criado method, leading to greatly improved calculation performance over the entire conversion range. The reaction, second-order F2, describes the pyrolysis reaction models of RLK. With the Arrhenius parameters obtained from the fitting model of CR, we attempt to reconstruct the temperature-dependent mass conversion curves and have resulted in generally acceptable results. Based on the Arrhenius parameter values obtained by Kissinger equation, the changes in entropy, enthalpy and Gibbs free energy, and lifetime predictions have been estimated concerning the thermal degradation processes of RLK.

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Comparison of CO2 gasification of coal in isothermal and non-isothermal conditions

E3S Web of Conferences ◽

10.1051/e3sconf/201910802017 ◽

2019 ◽

Vol 108 ◽

pp. 02017

Author(s):

Grzegorz Czerski ◽

Przemysław Grzywacz ◽

Katarzyna Śpiewak

Keyword(s):

Kinetic Parameters ◽

Bituminous Coal ◽

Conversion Degree ◽

Heating Rates ◽

Exponential Factor ◽

Isothermal Method ◽

Isothermal Conditions ◽

Thermogravimetric Analyzer ◽

Gasification Process ◽

Gasification Reaction

The thermogravimetric method allows to carry out measurements both in isothermal conditions for a given temperature and in non-isothermal conditions at a set heating rate. The aim of the work was to compare the process of gasification of the same coal in an atmosphere of CO2 under isothermal and non-isothermal conditions. The measurements were carried out with the use of DynTHERM Thermogravimetric analyzer by Rubotherm. Char derived from Polish bituminous coal “Janina” was used as material for gasification. In case of the isothermal method the measurements were performed at three temperatures – 850 °C, 900 °C and 950 °C, while in case of the non-isothermal method for three heating rates, i.e. 3 K/min, 5 K/min and 10 K/min. Based on the results obtained, kinetics curves of conversion degree of the gasification process were developed and kinetic parameters of the gasification reaction i.e. reaction order, activation energy and pre-exponential factor were determined. The values of the kinetic parameters obtained from measurements performed in isothermal and non-isothermal conditions were compared.

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Calculation of Kinetic Parameters of Thermal Decomposition of Forest Waste using the Monte Carlo Technique

Environmental and Climate Technologies ◽

10.2478/rtuect-2020-0010 ◽

2020 ◽

Vol 24 (1) ◽

pp. 162-170

Author(s):

Alok Dhaundiyal ◽

Laszlo Toth

Keyword(s):

Activation Energy ◽

Monte Carlo ◽

Kinetic Parameters ◽

Preexponential Factor ◽

Thermal Conversion ◽

Inert Atmosphere ◽

Monte Carlo Technique ◽

Heating Rates ◽

Forest Waste ◽

Distribution Parameters

AbstractThis paper deals with the pyrolysis of forest waste in the presence of an inert atmosphere. Experiments are carried out at different heating rates (5 °C, 10 °C and 15 °C) to determine derivative thermogravimetric behaviour of the material. Unlike the conventional scheme, the Monte Carlo technique is implemented to solve the distributed activation energy model (DAEM). DAEM is transformed into the inverse pyrolysis problem to determine the kinetic parameters of thermal degradation of forest waste. Activation energy, the preexponential factor and the distribution parameters are estimated by introducing the Monte Carlo Technique in the thermal conversion process.

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Thermo-catalytic decomposition of polystyrene waste: Comparative analysis using different kinetic models

Waste Management & Research ◽

10.1177/0734242x19865339 ◽

2019 ◽

Vol 38 (2) ◽

pp. 202-212 ◽

Cited By ~ 14

Author(s):

Ghulam Ali ◽

Jan Nisar ◽

Munawar Iqbal ◽

Afzal Shah ◽

Mazhar Abbas ◽

...

Keyword(s):

Activation Energy ◽

Copper Oxide ◽

Solid Waste ◽

Thermodynamic Parameters ◽

Model Fitting ◽

Catalytic Decomposition ◽

Decomposition Reaction ◽

Inert Atmosphere ◽

Heating Rates ◽

Model Free

Due to a huge increase in polymer production, a tremendous increase in municipal solid waste is observed. Every year the existing landfills for disposal of waste polymers decrease and the effective recycling techniques for waste polymers are getting more and more important. In this work pyrolysis of waste polystyrene was performed in the presence of a laboratory synthesized copper oxide. The samples were pyrolyzed at different heating rates that is, 5°Cmin−1, 10°Cmin−1, 15°Cmin−1 and 20°Cmin−1 in a thermogravimetric analyzer in inert atmosphere using nitrogen. Thermogravimetric data were interpreted using various model fitting (Coats–Redfern) and model free methods (Ozawa–Flynn–Wall, Kissinger–Akahira–Sunose and Friedman). Thermodynamic parameters for the reaction were also determined. The activation energy calculated applying Coats–Redfern, Ozawa–Flynn–Wall, Kissinger–Akahira–Sunose and Friedman models were found in the ranges 105–148.48 kJmol−1, 99.41–140.52 kJmol−1, 103.67–149.15 kJmol−1 and 99.93–141.25 kJmol−1, respectively. The lowest activation energy for polystyrene degradation in the presence of copper oxide indicates the suitability of catalyst for the decomposition reaction to take place at lower temperature. Moreover, the obtained kinetics and thermodynamic parameters would be very helpful in determining the reaction mechanism of the solid waste in a real system.

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Kinetic analysis of the pyrolysis of apricot stone and its main components via distributed activation energy mode

BioResources ◽

10.15376/biores.15.1.1187-1204 ◽

2020 ◽

Vol 15 (1) ◽

pp. 1187-1204

Author(s):

Huanhuan Ma ◽

Yimeng Zhang ◽

Liangcai Wang ◽

Zhengxiang Zhu ◽

Yu Chen ◽

...

Keyword(s):

Activation Energy ◽

Energy Distribution ◽

Apparent Activation Energy ◽

Early Stage ◽

Conversion Degree ◽

Heating Rates ◽

Continuous Increase ◽

Thermogravimetric Analyzer ◽

Energy Mode ◽

Main Components

The kinetics of pyrolysis of apricot stone and its main components, i.e., lignin, cellulose, and hemicellulose, were investigated via distributed activation energy mode. Experiments were done in a thermogravimetric analyzer at heating rates of 10, 20, 30, and 40 K·min-1 under nitrogen. The activation energy distribution peaks for the apricot stone, lignin, cellulose, and hemicellulose were centered at 246, 318, 364, and 170 kJ·mol-1, respectively. The activation energy distribution for the apricot stone slightly changed; lignin exhibited the widest distribution; and cellulose exhibited the highest activation energy at a conversion degree (α) of less than 0.75. At low pyrolysis temperatures (400 K to 600 K), the pyrolysis of hemicellulose was the main pyrolysis reaction. The apparent activation energy for the apricot stone mainly depended on the pyrolysis of hemicellulose and a small amount of lignin, and the activation energy was low in the early stage of pyrolysis. With the continuous increase in the pyrolysis temperatures (600 K to 660 K), the thermal weight loss of cellulose and lignin was intense. The apparent activation energy for the apricot stone mainly resulted from the pyrolysis of cellulose and lignin, and a higher activation energy was observed in the later stage of pyrolysis.

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Thermal degradation kinetics of oxo-degradable PP/PLA blends

Journal of Polymer Engineering ◽

10.1515/polyeng-2018-0073 ◽

2018 ◽

Vol 39 (1) ◽

pp. 58-67 ◽

Cited By ~ 4

Author(s):

Dev K. Mandal ◽

Haripada Bhunia ◽

Pramod K. Bajpai

Keyword(s):

Activation Energy ◽

Thermal Stability ◽

Thermogravimetric Analysis ◽

Thermal Degradation ◽

Kinetic Parameters ◽

Degradation Kinetics ◽

Nitrogen Atmosphere ◽

Thermal Degradation Kinetics ◽

Heating Rates ◽

Kinetics Of

AbstractIn this article, the influence of polylactide and pro-oxidant on the thermal stability, degradation kinetics, and lifetime of polypropylene has been investigated using thermogravimetric analysis under nitrogen atmosphere at four different heating rates (i.e. 5, 10, 15, and 20°C/min). The kinetic parameters of degradation were studied over a temperature range of 30–550°C. The derivative thermogravimetric curves have indicated single stage and two stage degradation processes. The activation energy was evaluated by using the Kissinger, Kim-Park, and Flynn-Wall methods under the nitrogen atmosphere. The activation energy value of polypropylene was much higher than that of polylactide. Addition of polylactide and pro-oxidant in polypropylene decreased the activation energy. The lifetime of polypropylene has also decreased with the addition of polylactide and pro-oxidant.

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Devolatilization Kinetics of Different Types of Bio-Coals Using Thermogravimetric Analysis

Metals ◽

10.3390/met9020168 ◽

2019 ◽

Vol 9 (2) ◽

pp. 168 ◽

Cited By ~ 6

Author(s):

Asmaa A. El-Tawil ◽

Lena Sundqvist Ökvist ◽

Hesham M. Ahmed ◽

Bo Björkman

Keyword(s):

Iron Oxide ◽

Inert Atmosphere ◽

Volatile Matter ◽

Conversion Degree ◽

Heating Rates ◽

Metal Quality ◽

Reduction Of Iron ◽

Thermogravimetric Data ◽

Lower Temperature ◽

Reducing Gases

The interest of the steel industry in utilizing bio-coal (pre-treated biomass) as CO2-neutral carbon in iron-making is increasing due to the need to reduce fossil CO2 emission. In order to select a suitable bio-coal to be contained in agglomerates with iron oxide, the current study aims at investigating the thermal devolatilization of different bio-coals. A thermogravimetric analyzer (TGA) equipped with a quadrupole mass spectrometer (QMS) was used to monitor the weight loss and off-gases during non-isothermal tests with bio-coals having different contents of volatile matter. The samples were heated in an inert atmosphere to 1200 °C at three different heating rates: 5, 10, and 15 °C/min. H2, CO, and hydrocarbons that may contribute to the reduction of iron oxide if contained in the self-reducing composite were detected by QMS. To explore the devolatilization behavior for different materials, the thermogravimetric data were evaluated by using the Kissinger– Akahira–Sonuse (KAS) iso-conversional model. The activation energy was determined as a function of the conversion degree. Bio-coals with both low and high volatile content could produce reducing gases that can contribute to the reduction of iron oxide in bio-agglomerates and hot metal quality in the sustained blast furnace process. However, bio-coals containing significant amounts of CaO and K2O enhanced the devolatilization and released the volatiles at lower temperature.

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Comparison of the dehydration kinetics of solid state compounds of 2-methoxybenzylidenepyruvate with some divalent metal ions

Eclética Química ◽

10.1590/s0100-46702010000100001 ◽

2010 ◽

Vol 35 (1) ◽

pp. 7-18

Author(s):

M. Kobelnik ◽

C. A. Ribeiro ◽

D. S. Dias ◽

G. A. Bernabé ◽

M. S. Crespi

Keyword(s):

Activation Energy ◽

Solid State ◽

Nitrogen Atmosphere ◽

Divalent Metal ◽

Point Of View ◽

Conversion Degree ◽

Divalent Metal Ions ◽

Heating Rates ◽

Exponential Factor ◽

Kinetics Of

Divalent metal complexes of ligand 2-methoxybenzylidenepyruvate with Fe, Co, Ni, Cu and Zn as well as sodium salt were synthesized and investigated in the solid state. TG curves of these compounds were obtained with masses sample of 1 and 5mg under nitrogen atmosphere. Different heating rates were used to characterize and study these compounds from the kinetic point of view. The activation energy and pre-exponential factor were obtained applying the Wall-Flynn-Ozawa method to the TG curves. The obtained data were evaluated and the values of activation energy (Ea / kJ mol-1) was plotted in function of the conversion degree (α). The results show that due to mass sample, different activation energies were obtained. The results are discussed mainly taking into account the linear dependence between the activation energy and the pre exponential factor, where was verified the effect of kinetic compensation (KCE) and possible linear relations between the dehydrations steps of these compounds.

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Kinetic analysis of oil palm empty fruit bunch (OPEFB) pellets as feedstock for pyrolysis

10.7287/peerj.preprints.1150 ◽

2015 ◽

Author(s):

Bemgba Bevan Nyakuma

Keyword(s):

Activation Energy ◽

Oil Palm ◽

Room Temperature ◽

Energy Requirement ◽

Inert Atmosphere ◽

Decomposition Kinetics ◽

The Other ◽

Empty Fruit Bunch ◽

Heating Rates ◽

Kinetics Of

The thermal behaviour and decomposition kinetics of pelletized oil palm empty fruit bunch (OPEFB) was investigated in this study using thermogravimetric analysis (TGA). The OPEFB pellets were heated from room temperature to 1000 ºC at different heating rates; 5, 10 and 20 °C min-1 under inert atmosphere. Thermal degradation occurred in three steps; drying, devolatization and char decomposition. Subsequently, the Popescu method was applied to the TG/DTG data to determine the kinetic parameters of the OPEFB pellets. The activation energy, E, for different degrees of conversion, α = 0.05 to 0.7 are 36.60 kJ/mol to 233.90 kJ/mol with high correlation R2 values. In addition, the drying and decomposition of lignin reactions displayed lower E values compared to the devolatization characterized by high E value of 233 kJ/mol at α = 0.2. This indicates that the devolatization process is slower and requires higher energy requirement to reach completion than the other stages of thermal decomposition of the fuel under inert atmosphere. Keywords: decomposition, kinetics, oil palm, empty fruit bunch, pyrolysis.

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