A Kinetic Study of Wetland Plant Suaeda salsa L. Pyrolysis Using Thermogravimetric Analyzer

2013 ◽  
Vol 848 ◽  
pp. 126-130
Author(s):  
Hua Xiao Yan ◽  
Hui Zhao ◽  
Qi Liu ◽  
Yan Xiang Ai ◽  
Yan Zhang ◽  
...  
Keyword(s):  
Activation Energy ◽  
Three Dimensional ◽  
Nitrogen Atmosphere ◽  
Suaeda Salsa ◽  
Good Prospect ◽  
Heating Rates ◽  
Thermogravimetric Analyzer ◽  
Exponential Factors ◽  
Pyrolysis Feedstock ◽  
Diffusion Function

The Suaeda salsa L. has been discovered to be a great potential as a new kind of renewable energy. The pyrolytic characteristics and kinetics of S. salsa were investigated at heating rates of 5, 10, 20, 30°C/min under nitrogen atmosphere respectively. The most probable mechanism function was deduced using Popescu method, which is a three-dimensional diffusion function (), and n=-2/3. Activation energy and pre-exponential factors were studied through the FWO, KAS and Popescu methods. The results showed that the activation energy increase as the pyrolysis process and three stages were observed in the TG-DTG curves of S.salsa. The results showed that S.salsa as a pyrolysis feedstock has a great potential and a good prospect in bio-oil production.

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

BioResources ◽  
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.

Thermal degradation kinetics of oxo-degradable PP/PLA blends

2018 ◽  
Vol 39 (1) ◽  
pp. 58-67 ◽  
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.

Pyrolysis Characteristics of Rice Husk Using TG-DTG Analysis

2013 ◽  
Vol 291-294 ◽  
pp. 351-354
Author(s):  
Qing Wang ◽  
Chun Xia Jia ◽  
Hong Peng Liu
Keyword(s):  
Activation Energy ◽  
Rice Husk ◽  
Frequency Factor ◽  
Weight Loss Curve ◽  
Heating Rates ◽  
Pyrolysis Characteristics ◽  
Thermogravimetric Analyzer ◽  
Purge Gas ◽  
Arrhenius Plot Method ◽  
Pyrolysis Kinetic

The rice husk from China has been non-isothermally pyrolysed on thermogravimetric analyzer(TGA). The analyses were performed at different heating rates (20, 40, 60, 80, 100°C/min) up to 900°C with nitrogen as purge gas. The weight loss curve showed that the main pyrolysis of rice husk took place in the range of 200~500°C. On the basis of experiment data, a pyrolysis kinetic model was proposed. The kinetic parameters of activation energy(E) and frequency factor(A) were obtained by the Direct Arrhenius Plot Method. There was no clear relationship between activation energy and heating rate.

scholarly journals Pyrolysis kinetics and thermal decomposition behavior of polycarbonate - a TGA-FTIR study

2014 ◽  
Vol 18 (3) ◽  
pp. 833-842 ◽  
Author(s):  
Esin Apaydin-Varol ◽  
Sevgi Polat ◽  
Ayse Putun
Keyword(s):  
Activation Energy ◽  
Fourier Transform ◽  
Reaction Order ◽  
Fourier Transform Infrared ◽  
Pyrolysis Kinetics ◽  
Heating Rates ◽  
Exponential Factor ◽  
Thermogravimetric Analyzer ◽  
Fourier Transform Infrared Spectrometer ◽  
Infrared Spectrometer

This study covers the thermal degradation of polycarbonate by means of Thermogravimetric Analyzer coupled with Fourier transform infrared spectrometer (TGA-FTIR). Thermogravimetric analysis of polycarbonate was carried out at four different heating rates of 5, 10, 15, and 20?C per minute from 25?C to 1000?C under nitrogen atmosphere. The results indicated that polycarbonate was decomposed in the temperature range of 425-600?C. The kinetic parameters, such as activation energy, pre-exponential factor and reaction order were determined using five different kinetic models; namely Coast-Redfern, Friedman, Kissinger, Flynn-Wall-Ozawa (FWO), and Kissinger-Akahira-Sunose (KAS). Overall decomposition reaction order was determined by Coats-Redfern method as 1.5. Average activation energy was calculated as 150.42, 230.76, 216.97, and 218.56 kJ/mol by using Kissinger, Friedman, FWO, and KAS models, respectively. Furthermore, the main gases released during the pyrolysis of polycarbonate were determined as CO2, CH4, CO, H2O, and other lower molecular weight hydrocarbons such as aldehydes, ketones and carbonyls by using thermogravimetric analyzer coupled with Fourier transform infrared spectrometer.

Pyrolysis Characteristics of Oil Sands

2012 ◽  
Vol 614-615 ◽  
pp. 111-114 ◽  
Author(s):  
Chun Xia Jia ◽  
Qing Wang ◽  
Xin Yu Zhang ◽  
Yin Wang
Keyword(s):  
Activation Energy ◽  
Oil Sands ◽  
Frequency Factor ◽  
Weight Loss Curve ◽  
Oil Sand ◽  
Heating Rates ◽  
Pyrolysis Characteristics ◽  
Thermogravimetric Analyzer ◽  
Purge Gas ◽  
Pyrolysis Kinetic

Three oil sand samples from Indonesia have been non-isothermally pyrolysed on thermogravimetric analyzer (TGA). The analyses were performed at different heating rates (5, 15 and 25oC/min) up to 850oC with nitrogen as purge gas. The weight loss curve shows that the main pyrolysis of oil sand takes place in the range of 200~600oC. On the basis of experimental data, a pyrolysis kinetic model was proposed. The kinetic parameters of activation energy (E) and frequency factor (A) were obtained by Integral Method. There is no clear relationship between activation energy and heating rate.

Study on the Pyrolysis Characteristics and Mechanism of KCl-Pretreated Sunflower Stalk

2013 ◽  
Vol 448-453 ◽  
pp. 1665-1674
Author(s):  
Dong Yu Chen ◽  
Qing Yu Liu ◽  
Yan Qing Hu
Keyword(s):  
Activation Energy ◽  
Heating Rate ◽  
Three Dimensional ◽  
Kinetic Mechanism ◽  
Metal Salts ◽  
Pyrolysis Kinetics ◽  
Heating Rates ◽  
Energy Value ◽  
Pyrolysis Characteristics ◽  
Mechanism Model

To study the influence of KCl pretreating on the pyrolysis kinetics of sunflower stalk, the pyrolysis of sunflower stalk pretreated by different concentration KCl solutions were performed by nonisothermal thermogravimetric analysis (TGA) at five different heating rates. The Ozawa and Kissinger methods were employed to calculate the activation energy and the Šatava method was used to obtain the kinetic mechanism model. The results showed that the pyrolysis process of the sunflower stalk pretreated by 3% and 10% KCl solution can be separated into four stages (water loss, depolymerization and vitrification, thermal decomposition, and carbonization). With the heating rate increasing, the main pyrolysis zone of the TG (thermogravimetric) and DTG curves move to the higher temperature direction, and the maximum pyrolysis rate and its corresponding temperature increase too. Adding a small amount of metal salts is conducive to the formation of volatile, and a certain amount of metal salts can improve the charcoal yield. More KCl additive makes the lower activation energy value, and the obtained activation energy value increases with the heating rate increasing. By means of the Šatava method, the kinetic mechanism model for the pyrolysis of KCl-pretreated sunflower stalk is Zhuralev-Lesakin-Tempelman equation, which is three-dimensional diffusion.

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

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.

Pyrolytic Behavior and Kinetic Analysis of Wheat Straw and Lignocellulosic Biomass Model Compound

2013 ◽  
Vol 860-863 ◽  
pp. 550-554 ◽  
Author(s):  
Zhi Qiang Wu ◽  
Shu Zhong Wang ◽  
Jun Zhao ◽  
Lin Chen ◽  
Hai Yu Meng
Keyword(s):  
Activation Energy ◽  
Kinetic Analysis ◽  
Wheat Straw ◽  
Lignocellulosic Biomass ◽  
Nitrogen Atmosphere ◽  
Thermochemical Conversion ◽  
Heating Rates ◽  
Decomposition Rates ◽  
Model Compounds ◽  
Pyrolysis Of Biomass

From a carbon cycle perspective, the thermochemical conversion of lignocellulosic biomass is inherently carbon neutral. Pyrolysis of biomass for energy supplying, such as bio-oil and bio-char, has been attracted much attention worldwide. Successful understanding the fundamental issues about the pyrolysis, including pyrolytic behavior and kinetic analysis of lignocellulosic biomass model compounds and real biomass, is essential for the further understanding and optimizing the pyrolysis process. In this paper, pyrolytic behavior of a typical lignocellulosic agricultural residue (wheat straw) and model compounds (cellulose) were measured through thermogravimetric analysis with various heating rates (10, 20, 40 °C·min-1) under nitrogen atmosphere. The results indicated that the interval of the weight loss for both wheat straw and cellulose moved upwards with the increment of heating rates. The maximum decomposition rates of cellulose were higher than those of wheat straw, and the temperature of maximum decomposition rates increased with the heating rates. Values of activation energy were solved through iso-conversional method. And the average values of activation energy for wheat straw and cellulose were 146.89 kJ·mol-1 and 134.56 kJ·mol-1 calculated from Flynn-Wall-Ozawa method, 144.05 kJ·mol-1 and 130.91 kJ·mol-1 calculated from Kissinger-Akahira-Sunose method, respectively.

scholarly journals Kinetics of Thermal Degradation of Viscose Fiber and Fire Retardant Viscose Fiber

2014 ◽  
Vol 9 (2) ◽  
pp. 155892501400900
Author(s):  
Tao Wang ◽  
Xianlin Xu ◽  
Yanlin Ren ◽  
Songtao Qin ◽  
Xiaoyang Sui ◽  
...  
Keyword(s):  
Activation Energy ◽  
Three Dimensional ◽  
Fire Retardant ◽  
Kinetic Mechanism ◽  
Viscose Fiber ◽  
Heating Rates ◽  
Exponential Factor ◽  
Air Atmosphere ◽  
Fwo Method ◽  
Mechanism Function

The thermal decomposition behavior of fire retardant viscose fiber and viscose fiber were studied by thermogravimetric analysis (TGA) under air atmosphere at heating rates of 10, 20, 30 and 40oC/min. The activation energy and pre-exponential factor were calculated by using the Kissinger method, Flynn-Wall-Ozawa (FWO) method and Satava-Sestak method. The results show that the activation energy for the fire retardant viscose fiber calculated by Kissinger and FWO method was 102.51kJ/mol and 103.73kJ/mol, respectively. The activation energy for viscose fiber calculated by Kissinger and FWO method was 103.58 kJ/mol and 104.83kJ/mol, respectively. The kinetic mechanism function of fire retardant viscose fiber was G(α) = [(1+ α)13-1]2 following a kinetic model of three-dimensional diffusion and the kinetic mechanism function of viscose fiber was G(α) = α3/2 following the power function rule.

Kinetic study of wood chips decomposition by TGA

2010 ◽  
Vol 64 (2) ◽  
Author(s):  
Lukáš Gašparovič ◽  
Zuzana Koreňová ◽  
Ľudovít Jelemenský
Keyword(s):  
Activation Energy ◽  
Kinetic Parameters ◽  
Isoconversional Method ◽  
Nitrogen Atmosphere ◽  
Decomposition Process ◽  
Wood Chips ◽  
Water Evaporation ◽  
Heating Rates ◽  
Exponential Factor ◽  
Decomposition Processes

AbstractPyrolysis of a wood chips mixture and main wood compounds such as hemicellulose, cellulose and lignin was investigated by thermogravimetry. The investigation was carried out in inert nitrogen atmosphere with temperatures ranging from 20°C to 900°C for four heating rates: 2 K min−1, 5 K min−1, 10 K min−1, and 15 K min−1. Hemicellulose, cellulose, and lignin were used as the main compounds of biomass. TGA and DTG temperature dependencies were evaluated. Decomposition processes proceed in three main stages: water evaporation, and active and passive pyrolysis. The decomposition of hemicellulose and cellulose takes place in the temperature range of 200–380°C and 250–380°C, while lignin decomposition seems to be ranging from 180°C up to 900°C. The isoconversional method was used to determine kinetic parameters such as activation energy and pre-exponential factor mainly in the stage of active pyrolysis and partially in the passive stage. It was found that, at the end of the decomposition process, the value of activation energy decreases. Reaction order does not have a significant influence on the process because of the high value of the pre-exponential factor. Obtained kinetic parameters were used to calculate simulated decompositions at different heating rates. Experimental data compared with the simulation ones were in good accordance at all heating rates. From the pyrolysis of hemicellulose, cellulose, and lignin it is clear that the decomposition process of wood is dependent on the composition and concentration of the main compounds.

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