Pyrolysis Kinetics Equation of Larch Bark

The larch bark was examined by non-isothermal means to determine the mass loss kinetics of the thermal decomposition with linear temperature programming in nitrogen atmosphere. In this work, mechanism equation of = was used forCoats-Redfern integral methodat the different heating rates. The apparent activation energy, pre-exponential factor and the pyrolysis kinetic equations at the different heating rates were obtained. The pyrolysis temperature area was divided into two separate temperature regions for the pyrolysis kinetic equation and the two components were decomposed respectively at the two separate temperature regions. The global mass loss rate of the bark is considered as controlled respectively by the reactions of the two components respectively during the lower and higher temperature ranges. The kinetics of the two components are found to abide by the mechanism equation of =, which gave the best fits to the experimental data. The obtained kinetic equations of the bark at the different heating rates were additionally validated by the reasonable agreement between the experimental and calculated results.

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Pyrolysis kinetics of recycled polyesters

International Journal of Clothing Science and Technology ◽

10.1108/ijcst-04-2014-0048 ◽

2015 ◽

Vol 27 (4) ◽

pp. 523-531 ◽

Cited By ~ 2

Author(s):

Jaber Al-Juaidiyah

Keyword(s):

Textile Industry ◽

Degradation Kinetics ◽

Nitrogen Atmosphere ◽

Coefficient Of Determination ◽

Pyrolysis Kinetics ◽

Polybutylene Terephthalate ◽

Exponential Factor ◽

Content Type ◽

Kissinger Model ◽

Kinetics Of

Purpose – The purpose of this paper is to study the non-isothermal degradation kinetics of recycled polybutylene terephthalate, polytrimethylene terephthalate and polyethylene terephthalate using thermogravimetric analysis (TGA) in a nitrogen atmosphere. Design/methodology/approach – To achieve this goal, the author utilized standard kinetic models, such as Coats-Redfern and Kissinger equations, for analysis of the TGA data. Findings – When applied to the TGA data, the Kissinger model resulted in a coefficient of determination (R2) value greater than 0.99. Originality/value – This study describes the maiden application of the Kissinger model to obtain the pre-exponential factor (A) and activation energy (E) for different polyester systems used in the textile industry.

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Pyrolysis of Sugarcane Bagasse: A Consecutive Reactions Kinetic Model from TGA Experiments

Materials Science Forum ◽

10.4028/www.scientific.net/msf.660-661.593 ◽

2010 ◽

Vol 660-661 ◽

pp. 593-598 ◽

Cited By ~ 6

Author(s):

Kássia Graciele dos Santos ◽

Taisa S. Lira ◽

Valéria V. Murata ◽

Marco Gianesella ◽

Marcos A.S. Barrozo

Keyword(s):

Kinetic Model ◽

Sugarcane Bagasse ◽

Room Temperature ◽

Linear Method ◽

Pyrolysis Kinetics ◽

Heating Rates ◽

Exponential Factor ◽

Consecutive Reactions ◽

Kinetics Of ◽

Good Agreement

The pyrolysis kinetics of sugarcane bagasse in nitrogen flow was studied by thermogravimetric analysis from room temperature to 1173 K at different heating rates (1.5, 3, 5, 10, 15, 20, 30 and 50 K/min). As there are three distinct devolatilization peaks in the DTG curve, each peak was associated to thermal decomposition of an individual biomass subcomponent (hemicellulose, cellulose and lignin). The kinetic model adopted was a consecutive reactions model. The kinetic parameters of the pyrolysis process, such as activation energy and pre-exponential factor, were calculated by least squares non-linear method and Scilab are used as the simulation tool. The simulated results showed a good agreement with the experimental data and the parameters found are similar to reported by the literature.

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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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Influence of Liming on Kinetics of Sewage Sludge Pyrolysis

Ecological Chemistry and Engineering S ◽

10.1515/eces-2019-0013 ◽

2019 ◽

Vol 26 (1) ◽

pp. 175-188

Author(s):

Paweł Stolarek ◽

Stanisław Ledakowicz ◽

Radosław Ślęzak

Keyword(s):

Thermal Decomposition ◽

Sewage Sludge ◽

Mass Loss ◽

Kinetic Parameters ◽

Heating Rate ◽

Visual Analysis ◽

Pyrolysis Kinetics ◽

Exponential Factor ◽

The Impact ◽

Kinetics Of

Abstract Thermogravimetry (TG) is the fast and reliable method for characterization of thermal decomposition of any material and in particular to determine the kinetics of pyrolytic decomposition of sewage sludge. Two types of sewage sludge with and without addition of lime were investigated from kinetic point of view. For TG analysis samples of selected sewage sludge were heated under the inert atmosphere of argon with constant heating rate from 303 to 1273 K; the three heating rate β = 5, 10 and 20 K/min were chosen. The iso-conversion methods of Friedman and Ozawa-Flynn-Wall were employed for analysis of TG results. As the sewage sludge decomposition is very complex process it cannot be described by a simple stoichiometric equation, therefore the so called lumping of reactions in the selected temperature ranges were used with detailed principles arising from visual analysis of DTG curve. The deconvolution of DTG curves performed according to Fraser-Suzuki asymmetric profile allowed the identification of number of lumps and their contribution to the overall mass loss. So the decomposition of sewage sludge with lime addition could be described with five groups of reactions while the one without lime by means of six lumps. The thermal decomposition of sewage sludge was assumed to proceed according to the scheme of parallel concurrent independent reactions of n-th order. The values of the apparent activation energies at different constant values of conversion degrees were determined by the iso-conversion analysis. To estimate the kinetic parameters the non-linear regression with Levenberg-Marquart optimization procedure was used. The kinetic parameters such as activation energy, pre-exponential factor, reaction order and fraction of total mass loss associated with a given reaction were determined. The impact of sewage sludge liming revealed in essential differences of pyrolysis products and pyrolysis kinetics of limed sludge and without lime one was highlighted.

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An Experimental Study of the Coking Process

International Journal of Chemical Reactor Engineering ◽

10.2202/1542-6580.2001 ◽

2010 ◽

Vol 8 (1) ◽

Author(s):

Somayeh Ebrahimi ◽

Jafarsadegh Moghaddas

Keyword(s):

Activation Energy ◽

Coke Formation ◽

Nitrogen Atmosphere ◽

Fuel Oil ◽

Effective Parameters ◽

Pyrolysis Kinetics ◽

Exponential Factor ◽

First Order ◽

First Order Kinetics ◽

Kinetics Of

The coking process includes two dynamic and isothermal steps. In this process, some factors control the coke formation kinetics. In this research, effects of some important and effective parameters of feed on the quality of petroleum coke were studied. Two hydrocarbon residue feeds; Cracked Fuel Oil (CFO) and Styrene Monomer Tar (SMTAR) were used at 500°C with atmospheric pressure of nitrogen used as an inert gas. Rate of weight loss and gas evolution from these feeds were considered by data of thermal analysis TG (thermogravimetry) and DTG (derivative thermogravimetry). Based on the results, CFO was assigned as the better feed. After selecting better feed, simultaneous thermogravimetry-differential analysis (TG-DTA) was used to study the pyrolysis kinetics of CFO. Samples were heated in a TG-DTA apparatus in nitrogen atmosphere at a temperature range of 37-600°C. The activation energy (Ea) and pre-exponential factor (A) were calculated from the experimental results by using a three stage Arrhenius-type kinetic model and showed that CFO pyrolysis kinetics at temperature ranges 37-285, 320-450 and 467-600°C follows first, second and first order kinetics, respectively. Attentive to temperature increase and reaction progress, activation energy and pre-exponential factor indicated different values at each stage. Also, kinetics of the isothermal step of coke formation was studied during heating of CFO. Samples were reacted in a tube furnace at 450°C and with nitrogen atmosphere. The kinetics of coke formation for petroleum residue was followed by solvent extraction (insolubility in hexane (HI), toluene (TI)) and a development of TI approximate to apparent first order kinetics. The rate constant at this temperature was calculated and it was also observed that the coke formation had been started at a temperature below 450°C.

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Study of thermal degradation behavior and kinetics of ABS/PC blend

Polish Journal of Chemical Technology ◽

10.2478/pjct-2020-0029 ◽

2020 ◽

Vol 22 (3) ◽

pp. 64-69

Author(s):

Saira Bano ◽

Naveed Ramzan ◽

Tanveer Iqbal ◽

Hamayoun Mahmood ◽

Farhan Saeed

Keyword(s):

Thermal Degradation ◽

Mass Loss ◽

Acrylonitrile Butadiene Styrene ◽

Entropy Change ◽

Heating Rates ◽

Exponential Factor ◽

Model Free ◽

Thermogravimetric Curve ◽

Thermal Degradation Behavior ◽

Kinetics Of

AbstractThis work investigated kinetics and thermal degradation of acrylonitrile butadiene styrene and polycarbonate (ABS/PC) blend using thermogravimetric analysis in the range of 25 to 520°C. For thermal degradation of blend, activation energy (Ea) and pre-exponential factor (A) were calculated under various heating rates as 5, 10, 15 and 20°C/min using iso-conversional model-free methods (Kissinger, Flynn-Wall- Ozawa and Friedman). Mass loss of the blend as a function of temperature was plotted as thermogravimetric curve (TG) while derivative values of mass loss were drawn as derivative thermogravimetric (DTG) curve. Using Kissinger method, Ea was 51.4 kJ/mol, while values calculated from FWO and Friedman method were 86–161 and 30–251 kJ/mol respectively. Results showed increasing trend of Ea with higher conversion values indicating different degradation mechanisms at the initial and final stages of the experiment. Thermodynamic parameters such as enthalpy change (ΔH), Gibbs free energy (ΔG) and entropy change (ΔS) were also calculated.

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Thermogravimetric Kinetics of Selected Energy Crops Pyrolysis

Energies ◽

10.3390/en13153977 ◽

2020 ◽

Vol 13 (15) ◽

pp. 3977

Author(s):

Magdalena Matusiak ◽

Radosław Ślęzak ◽

Stanisław Ledakowicz

Keyword(s):

Activation Energy ◽

Energy Crops ◽

Pyrolysis Kinetics ◽

Heating Rates ◽

Exponential Factor ◽

Miscanthus Giganteus ◽

Temperature Ranges ◽

The Given ◽

Kinetics Of ◽

Derivative Thermogravimetry

The main purpose of this paper was to compare the pyrolysis kinetics of three types of energy crops: Miscanthus giganteus, Sida hermaphrodita, and Sorghum Moench. Studies were conducted in thermobalance. Feedstock samples were heated up from ambient temperature to 600 °C under an inert argon atmosphere. Three heating rates of β = 5, 10, and 20 °C/min were applied. Reactions occurring in the given temperature ranges were grouped together into so-called lumps identified by the deconvolution of derivative thermogravimetry (DTG) curves that corresponded to biomass compositions (hemicellulose, cellulose, and lignin). For the estimation of the activation energy and pre-exponential factor, the Friedman and Ozawa–Flynn–Wall methods were used. The final kinetic parameters were determined by nonlinear regression assuming that thermal decomposition proceeded via three parallel independent reactions of the nth order. The activation energy of hemicellulose, cellulose and lignin was determined to be in the range of 92.9–97.7, 190.1–192.5, and 170–175.2 kJ/mol, respectively. The reaction order was in the range of 3.35–3.99 for hemicellulose, 1.38–1.93 for cellulose, and 3.97–3.99 for lignin. The obtained results allow us to estimate the pyrolytic potential of energy crops selected for this study, and can be used in designing efficient pyrolizers for these materials.

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Kinetic Study on Pyrolysis of Gentamicin Residue

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.955-959.2803 ◽

2014 ◽

Vol 955-959 ◽

pp. 2803-2808

Author(s):

Ren Ping Liu ◽

Rui Yao ◽

Hui Li

Keyword(s):

Activation Energy ◽

High Temperature ◽

Thermochemical Conversion ◽

Pyrolysis Kinetics ◽

Heating Rates ◽

Exponential Factor ◽

Thermogravimetric Analyzer ◽

Basic Work ◽

Mechanism Function ◽

Kinetics Of

Gentamicin bacteria residue contains high organic compound. The technology of thermochemical conversion can effectively solve the problem of bulk gentamicin residue disposal, research on pyrolysis kinetics of the reaction is the basic work for thermochemical conversion . In this paper, Pyrolysis experiments were carried out in a thermogravimetric analyzer under inert conditions and operated at different heating rates (5, 10, 20 K/min).Two different kinetic models, the iso-conversional Ozawa–Flynn–Wall (Ozawa) models and Satava method were applied on TGA data of gentamicin residue to calculate the kinetic parameters including activation energy, pre-exponential factor and Mechanism function. The results showed that: gentamicin bacteria residue lost most weight of it between 100-650 °C , about 74.23% of the whole sample can decompose under high temperature. The pyrolysis function for gentamicin residue should be G(α) =[-ln(1-α)]3.

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Comparison of the dehydration Kinetics of solid state compounds of 2-methoxybenzylidenepyruvate with some Divalent metal ions

Eclética Química Journal ◽

10.26850/1678-4618eqj.v35.1.2010.p07-18 ◽

2018 ◽

Vol 35 (1) ◽

pp. 07

Author(s):

Marcelo Kobelnik ◽

Clóvis Augusto Ribeiro ◽

Diógenes Dos Santos Dias ◽

Gisele Aparecida Bernabé ◽

Marisa Spirandeli 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

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Thermal Stability and Decomposition Kinetics of 1-Alkyl-2,3-Dimethylimidazolium Nitrate Ionic Liquids: TGA and DFT Study

Materials ◽

10.3390/ma14102560 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2560

Author(s):

Jianwen Meng ◽

Yong Pan ◽

Fan Yang ◽

Yanjun Wang ◽

Zhongyu Zheng ◽

...

Keyword(s):

Thermal Stability ◽

Density Functional Theory ◽

Ionic Liquids ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Nitrogen Atmosphere ◽

Decomposition Kinetics ◽

Heating Rates ◽

Functional Theory ◽

Kinetics Of

The thermal stability and decomposition kinetics analysis of 1-alkyl-2,3-dimethylimidazole nitrate ionic liquids with different alkyl chains (ethyl, butyl, hexyl, octyl and decyl) were investigated by using isothermal and nonisothermal thermogravimetric analysis combined with thermoanalytical kinetics calculations (Kissinger, Friedman and Flynn-Wall-Ozawa) and density functional theory (DFT) calculations. Isothermal experiments were performed in a nitrogen atmosphere at 240, 250, 260 and 270 °C. In addition, the nonisothermal experiments were carried out in nitrogen and air atmospheres from 30 to 600 °C with heating rates of 5, 10, 15, 20 and 25 °C/min. The results of two heating modes, three activation energy calculations and density functional theory calculations consistently showed that the thermal stability of 1-alkyl-2,3-dimethylimidazolium nitrate ionic liquids decreases with the increasing length of the alkyl chain of the substituent on the cation, and then the thermal hazard increases. This study could provide some guidance for the safety design and use of imidazolium nitrate ionic liquids for engineering.

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