Distributed Activation Energy Model for Thermal Decomposition of Polypropylene Waste

AbstractThermal decomposition kinetics of Polypropylene (PP) waste is extremely important with respect to valorisation of waste plastics and production of utilizable components viz. chemicals, fuel oil & gas. The present research study focuses on pyrolysis kinetics of PP waste, which is present as a fraction of municipal plastic waste through distributed activation energy model (DAEM). The decomposition kinetics for PP follows a Gaussian distribution, where the normal distribution curves were centred corresponding to activation energy of 224 kJ/mol. The standard deviation of the distribution for the PP sample was found to be 22 kJ/mol indicating its wider distribution of decomposition range. The data validation has been carried out by comparing the rate parameter and extent of conversion values calculated through DAEM model with the Thermogravimetric analysis (TGA) experiments carried out for PP at various heating rates of 5, 10, 20 and 40 °C/min.

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Thermal Decomposition Kinetics of RDX with Distributed Activation Energy Model

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.641-642.144 ◽

2013 ◽

Vol 641-642 ◽

pp. 144-147 ◽

Cited By ~ 2

Author(s):

Ming Hua Chen ◽

Tao Zhang ◽

Wen Ping Chang ◽

Xiao Biao Jia

Keyword(s):

Activation Energy ◽

Thermal Decomposition ◽

Energy Model ◽

Decomposition Kinetics ◽

Thermal Decomposition Kinetics ◽

Distributed Activation Energy Model ◽

Thermogravimetric Analyzer ◽

Decomposition Stage ◽

Decomposition Processes ◽

Kinetics Of

The thermal decomposition kinetics of RDX at different rates was studied by thermogravimetric analyzer(TG) and the activation energy of RDX was calculated by distributed activation energy model. It is shown that the thermal decomposition processes of RDX were divided into three stages according to the TG curves, they are molten stage, thermal decomposition stage and eng stage. The activation energies of RDX are all between 124.34 and 181.48KJ•mol-1 in the thermal decomposition stage of non-monotonously increasing. The activation energy of RDX is 139.98 KJ•mol-1 in the molten stage, and the thermal decomposition stage is167.24KJ•mol-1.

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Theoretical Analysis of Double Logistic Distributed Activation Energy Model for Thermal Decomposition Kinetics of Solid Fuels

Industrial & Engineering Chemistry Research ◽

10.1021/acs.iecr.8b01527 ◽

2018 ◽

Vol 57 (23) ◽

pp. 7817-7825 ◽

Cited By ~ 8

Author(s):

Zhujun Dong ◽

Yang Yang ◽

Wenfei Cai ◽

Yifeng He ◽

Meiyun Chai ◽

...

Keyword(s):

Activation Energy ◽

Thermal Decomposition ◽

Theoretical Analysis ◽

Energy Model ◽

Decomposition Kinetics ◽

Thermal Decomposition Kinetics ◽

Solid Fuels ◽

Distributed Activation Energy Model ◽

Kinetics Of

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Comparative study on the pyrolysis kinetics of polyurethane foam from waste refrigerators

Waste Management & Research ◽

10.1177/0734242x19877682 ◽

2019 ◽

Vol 38 (3) ◽

pp. 271-278 ◽

Cited By ~ 4

Author(s):

Zhitong Yao ◽

Shaoqi Yu ◽

Weiping Su ◽

Weihong Wu ◽

Junhong Tang ◽

...

Keyword(s):

Activation Energy ◽

Polyurethane Foam ◽

Model Fitting ◽

Energy Model ◽

Pyrolysis Kinetics ◽

Ozawa Method ◽

Heating Rates ◽

Distributed Activation Energy Model ◽

Model Free ◽

Kinetics Of

Thermal treatment offers advantages of significant volume reduction and energy recovery for the polyurethane foam from waste refrigerators. In this work, the pyrolysis kinetics of polyurethane foam was investigated using the model-fitting, model-free and distributed activation energy model methods. The thermogravimetric analysis indicated that the polyurethane foam decomposition could be divided into three stages with temperatures of 38°C–400°C, 400°C–550°C and 550°C–1000°C. Peak temperatures for the major decomposition stage (<400°C) were determined as 324°C, 342°C and 344°C for heating rates of 5, 15 and 25 K min-1, respectively. The activation energy ( Eα) from the Friedman, Flynn–Wall–Ozawa and Tang methods increased with degree of conversion ( α) in the range of 0.05 to 0.5. The coefficients from the Flynn–Wall–Ozawa method were larger and the resulted Eα values fell into the range of 163.980–328.190 kJ mol-1 with an average of 206.099 kJ mol-1. For the Coats–Redfern method, the diffusion models offered higher coefficients, but the E values were smaller than that from the Flynn–Wall–Ozawa method. The Eα values derived from the distributed activation energy model method were determined as 163.536–334.231 kJ mol-1, with an average of 206.799 kJ mol-1. The peak of activation energy distribution curve was located at 205.929 kJ mol-1, consistent with the thermogravimetric results. The Flynn–Wall–Ozawa and distributed activation energy model methods were more reliable for describing the polyurethane foam pyrolysis process.

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Thermal Decomposition Kinetics of Flame Retardant Polybutylene Terephthalate Matrix Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.956.181 ◽

2019 ◽

Vol 956 ◽

pp. 181-191

Author(s):

Jian Lin Xu ◽

Bing Xue Ma ◽

Cheng Hu Kang ◽

Cheng Cheng Xu ◽

Zhou Chen ◽

...

Keyword(s):

Activation Energy ◽

Thermal Decomposition ◽

Flame Retardant ◽

Mass Loss Rate ◽

Decomposition Reaction ◽

Decomposition Kinetics ◽

Thermal Decomposition Kinetics ◽

Heating Rates ◽

Polybutylene Terephthalate ◽

Kinetics Of

The thermal decomposition kinetics of polybutylene terephthalate (PBT) and flame-retardant PBT (FR-PBT) were investigated by thermogravimetric analysis at various heating rates. The kinetic parameters were determined by using Kissinger, Flynn-Wall-Ozawa and Friedman methods. The y (α) and z (α) master plots were used to identify the thermal decomposition model. The results show that the rate of residual carbon of FR-PBT is higher than that of PBT and the maximum mass loss rate of FR-PBT is lower than that of PBT. The values of activation energy of PBT (208.71 kJ/mol) and FR-PBT (244.78 kJ/mol) calculated by Kissinger method were higher than those of PBT (PBT: 195.54 kJ/mol) and FR-PBT (FR-PBT: 196.00 kJ/mol) calculated by Flynn-Wall-Ozawa method and those of PBT and FR-PBT (PBT: 199.10 kJ/mol, FR-PBT: 206.03 kJ/mol) calculated by Friedman methods. There is a common thing that the values of activation energy of FR-PBT are higher than that of PBT in different methods. The thermal decomposition reaction models of the PBT and FR-PBT can be described by Avarami-Erofeyev model (A1).

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Modelling of Thermal Decomposition Kinetics of Proteins, Carbohydrates and Lipids Using Scenedesmus microalgae thermal Data

Asian Journal of Chemistry ◽

10.14233/ajchem.2020.22768 ◽

2020 ◽

Vol 32 (11) ◽

pp. 2921-2926

Author(s):

BOTHWELL NYONI ◽

PHUTI TSIPA ◽

SIFUNDO DUMA ◽

SHAKA SHABANGU ◽

SHANGANYANE HLANGOTHI

Keyword(s):

Activation Energy ◽

Thermal Decomposition ◽

Bulk Material ◽

Decomposition Kinetics ◽

Second Order ◽

Thermal Decomposition Kinetics ◽

Heating Rates ◽

High Heating ◽

The Individual ◽

Kinetics Of

In present work, the thermal decomposition behaviour and kinetics of proteins, carbohydrates and lipids is studied by use of models derived from mass-loss data obtained from thermogravimetric analysis of Scenedesmus microalgae. The experimental results together with known decomposition temperature range values obtained from various literature were used in a deconvolution technique to model the thermal decomposition of proteins, carbohydrates and lipids. The models fitted well (R2 > 0.99) and revealed that the proteins have the highest reactivity followed by lipids and carbohydrates. Generally, the decomposition kinetics fitted well with the Coats-Redfern first and second order kinetics as evidenced by the high coefficients of determination (R2 > 0.9). For the experimental conditions used in this work (i.e. high heating rates), the thermal decomposition of protein follows second order kinetics with an activation energy in the range of 225.3-255.6 kJ/mol. The thermal decomposition of carbohydrate also follows second order kinetics with an activation energy in the range of 87.2-101.1 kJ/mol. The thermal decomposition of lipid follows first order kinetics with an activation energy in the range of 45-64.8 kJ/ mol. This work shows that the thermal decomposition kinetics of proteins, carbohydrates and lipids can be performed without the need of experimentally isolating the individual components from the bulk material. Furthermore, it was shown that at high heating rates, the decomposition temperatures of the individual components overlap resulting in some interactions that have a synergistic effect on the thermal reactivity of carbohydrates and lipids.

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Effect of anaerobic digestion on sequential pyrolysis kinetics of organic solid wastes using thermogravimetric analysis and distributed activation energy model

Bioresource Technology ◽

10.1016/j.biortech.2016.12.057 ◽

2017 ◽

Vol 227 ◽

pp. 297-307 ◽

Cited By ~ 19

Author(s):

Xiaowei Li ◽

Qingqing Mei ◽

Xiaohu Dai ◽

Guoji Ding

Keyword(s):

Activation Energy ◽

Anaerobic Digestion ◽

Thermogravimetric Analysis ◽

Energy Model ◽

Solid Wastes ◽

Pyrolysis Kinetics ◽

Distributed Activation Energy Model ◽

Organic Solid ◽

Organic Solid Wastes ◽

Kinetics Of

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Decomposition Kinetics of Switchgrass: Estimating Activation Energy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.881-883.726 ◽

2014 ◽

Vol 881-883 ◽

pp. 726-733

Author(s):

Gui Ying Xu ◽

Jiang Bo Wang ◽

Ling Ping Guo ◽

Guo Gang Sun

Keyword(s):

Activation Energy ◽

Thermal Decomposition ◽

Apparent Activation Energy ◽

High Purity ◽

Isoconversional Methods ◽

Decomposition Kinetics ◽

Heating Rates ◽

Model Free ◽

Chemical Utilization ◽

Kinetics Of

TG analysis was used to investigate the thermal decomposition of switchgrass, which is a potential gasification feedstock. 10 mg switchgrass sample with the particles between 0.45 and 0.70 mm was linearly heated to 873 K at heating rates of 10, 20, 30 K/min, respectively, under high-purity nitrogen. The Kissinger method and three isoconversional methods including Friedman, Flynn-wall-Ozawa, Vyazovkin and Lenikeocink methods were used to estimate the apparent activation energy of switchgrass. With the three isoconversional methods, it can be concluded that the activation energy increases with increasing conversion. The four model free methods reveal activation energies in the range of 70-460 kJ/mol. These activation energy values provide the basic data for the thermo-chemical utilization of the switchgrass.

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