Thermo-catalytic degradation of different consumer plastic wastes by zeolite a catalyst: A kinetic approach

2020 ◽  
pp. 147776062097240
Author(s):  
Sthitapragyan Patnaik ◽  
Aruna Kumar Barick ◽  
Achyut K Panda
Keyword(s):  
Activation Energy ◽  
Thermal Degradation ◽  
Research Work ◽  
Model Fitting ◽  
Catalytic Decomposition ◽  
Kinetic Approach ◽  
Zeolite A ◽  
Thermal Degradation Behavior ◽  
Plastic Wastes ◽  
One Step

This research work includes the effect of Zeolite-A catalyst on the thermal degradation behavior of six different consumer plastic wastes like high density polyethylene (HDPE), polypropylene (PP), polyethylene terephthalate (PET), polymethylene methacralate (PMMA), polystyrene (PS) and polytetrafluoro ethylene (PTFE) through kinetic approach by using thermogravimetric analysis (TGA) data. Kinetic parameters such as reaction order, activation energy, and Arrhenius constant for the degradation of different waste plastics is determined using model fitting Coats–Redfern method. All the plastics show one-step degradation in the temperature range of 300–600°C. There is a significant decrease in activation energy (Ea) for the thermo-catalytic decomposition of the plastics in presence of Zeolite A catalyst. The extent of catalytic effect is found different for different plastics in the order of HDPE < PP < PS < PET < PMMA < PTFE. The order of the thermal degradation reaction is also found different for different types of plastics. The order of the reaction is altered in case of PET, PS and PTFE in presence of the catalyst but it is unaffected in case of remaining plastics. This treatment would reduce the energy consumption of pyrolysis process and also make the process economical viable.

Thermal degradation kinetics and lifetime of HDPE/PLLA/pro-oxidant blends

2016 ◽  
Vol 36 (9) ◽  
pp. 917-931 ◽  
Author(s):  
Gaurav Madhu ◽  
Dev K. Mandal ◽  
Haripada Bhunia ◽  
Pramod K. Bajpai
Keyword(s):  
Activation Energy ◽  
Thermal Degradation ◽  
Degradation Kinetics ◽  
Model Fitting ◽  
Frequency Factor ◽  
Thermal Degradation Kinetics ◽  
Heating Rates ◽  
Model Free ◽  
Calculation Technique ◽  
Thermal Degradation Behavior

Abstract The effect of adding poly(L-lactic acid) (PLLA) with and without a pro-oxidant additive cobalt stearate (CoSt) and compatibilizer maleic anhydride grafted polyethylene (MA-g-PE) on the thermal degradation and stability of high-density polyethylene (HDPE) films was analyzed using thermogravimetric analysis (TGA). The kinetic parameters [i.e. activation energy (Ea), order of reaction (n), and frequency factor ln(A)] of the samples were studied over a temperature range of 25°C–600°C at four heating rates (i.e. 5, 10, 15, and 20°C/min) through model-free techniques (e.g. Friedman, second Kissinger, and Flynn-Wall-Ozawa) and model-fitting techniques (e.g. Freeman-Carroll and Kim-Park). The value of Ea for neat HDPE was found to be much higher than PLLA; for the HDPE/PLLA blend, it was nearer to that of HDPE. An increase in the activation energy of 80/20 (HDPE/PLLA) blend was noticed by the addition of MA-g-PE. The TGA data and degradation kinetics were also used to predict the lifetime of the film samples. The lifetime of HDPE was found to decrease with the increase in the concentration of CoSt, thereby revealing its pro-oxidative ability. Minimum lifetime was noted for the HDPE/PLLA (80/20) sample blended with CoSt, which increased slightly in the presence of MA-g-PE. Studies indicated that the thermal degradation behavior and lifetime of the investigated film samples depends not only on the fractions of their constituents but also on the heating rates and calculation technique.

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

2019 ◽  
Vol 38 (2) ◽  
pp. 202-212 ◽  
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.

scholarly journals Dynamic Model-Free and Model-Fitting Kinetic Analysis during Torrefaction of Oil Palm Frond Pellets

2020 ◽  
Vol 15 (1) ◽  
pp. 253-263
Author(s):  
Sharmeela Matali ◽  
Norazah Abd Rahman ◽  
Siti Shawalliah Idris ◽  
Nurhafizah Yaacob
Keyword(s):  
Activation Energy ◽  
Thermal Degradation ◽  
Oil Palm ◽  
Model Fitting ◽  
Integral Model ◽  
Model Free ◽  
Solid Biofuel ◽  
Oil Palm Frond ◽  
Kinetics Of ◽  
Palm Frond

Torrefaction is a thermal conversion method extensively used for improving the properties of biomass. Usually this process is conducted within a temperature range of 200-300 °C under an inert atmosphere with residence time up to 60 minutes. This work aimed to study the kinetic of thermal degradation of oil palm frond pellet (OPFP) as solid biofuel for bioenergy production. The kinetics of OPFP during torrefaction was studied using frequently used iso-conversional model fitting (Coats-Redfern (CR)) and integral model-free (Kissinger-Akahira-Sunose (KAS)) methods in order to provide effective apparent activation energy as a function of conversion. The thermal degradation experiments were conducted at four heating rates of 5, 10, 15, and 20 °C/min in a thermogravimetric analyzer (TGA) under non-oxidative atmosphere. The results revealed that thermal decomposition kinetics of OPFP during torrefaction is significantly influenced by the severity of torrefaction temperature. Via Coats-Redfern method, torrefaction degradation reaction mechanism follows that of reaction order with n = 1. The activation energy values were 239.03 kJ/mol and 109.28 kJ/mol based on KAS and CR models, respectively. Copyright © 2020 BCREC Group. All rights reserved 

scholarly journals Thermal and kinetic analysis of pure and contaminated ionic liquid: 1-butyl-2.3-dimethylimidazolium chloride (BDMIMCl)

2016 ◽  
Vol 18 (2) ◽  
pp. 122-125 ◽  
Author(s):  
Ayyaz Muhammad
Keyword(s):  
Activation Energy ◽  
Thermal Stability ◽  
Thermal Decomposition ◽  
Ionic Liquid ◽  
Thermal Degradation ◽  
Kinetic Analysis ◽  
Kinetic Parameters ◽  
Process Design ◽  
Research Work ◽  
Thermal Stability Of

Abstract In this research work, thermal decomposition and kinetic analysis of pure and contaminated imidazolium based ionic liquid (IL) has been investigated. As thermal decomposition and kinetics evaluation plays a pivotal role in effective process design. Therefore, thermal stability of pure 1-butyl-2,3-dimethylimidazolium chloride (BDMIMCl) was found to be higher than the sample of IL with the addition of 20% (wt.) NH4Cl as an impurity. The activation energy of thermal degradation of IL and other kinetic parameters were determined using Coats Redfern method. The activation energy for pure IL was reduced in the presence of NH4Cl as contaminant i.e., from 58.7 kJ/mol to 46.4 kJ/mol.

scholarly journals Study on Combustion Characteristics and Thermodynamic Parameters of Thermal Degradation of Guinea Grass (Megathyrsus maximus) in N2-Pyrolytic and Oxidative Atmospheres

2021 ◽  
Vol 14 (1) ◽  
pp. 112
Author(s):  
Ayokunle O. Balogun ◽  
Adekunle A. Adeleke ◽  
Peter P. Ikubanni ◽  
Samuel O. Adegoke ◽  
Abdulbaset M. Alayat ◽  
...  
Keyword(s):  
Activation Energy ◽  
Thermal Degradation ◽  
Thermodynamic Parameters ◽  
Mass Loss Rate ◽  
Model Fitting ◽  
Chemical Characterization ◽  
Crystallinity Index ◽  
Combustion Characteristics ◽  
Heating Rates ◽  
Guinea Grass

This study provides an extensive investigation on the kinetics, combustion characteristics, and thermodynamic parameters of the thermal degradation of guinea grass (Megathyrsus maximus) in N2-pyrolytic and oxidative atmospheres. A model-fitting technique and three different iso-conversional techniques were used to investigate the kinetics of the thermal process, after which an analysis of the combustion characteristics and thermodynamic parameters was undertaken. Prior to this, experiments on the physico-chemical characterization, thermogravimetric, and spectroscopic analyses were carried out to provide insight into the compositional structure of the guinea grass. The volatile matter, fixed carbon, and total lignin contents by mass were 73.0%, 16.1%, and 21.5%, respectively, while the higher heating value was 15.46 MJ/kg. The cellulose crystallinity index, determined by XRD, was 0.43. The conversion of the GG in air proceeded at a relatively much higher rate as the maximum mass-loss rate peak in a 20 K/min read was −23.1 and −12.3%/min for the oxidative and the pyrolytic, respectively. The kinetics investigation revealed three distinctive stages of decomposition with their corresponding values of activation energy. The average values of activation energy (FWO) at the latter stages of decomposition in the pyrolytic processes (165 kJ/mol) were higher than those in the oxidative processes (125 kJ/mol)—an indication of the distinctive phenomenon at this stage of the reaction. The Coats–Redfern kinetic model revealed that chemical reactions and diffusional models played a predominant role in the thermal decomposition process of the GG. This study showed that the thermodynamic parameters varied with the conversion ratio, and the combustion performance increased with the heating rates. The use of GG as an energy feedstock is recommended based on the findings from this work.

Fire Retardant Cellulose Characterized by Thermal Degradation Behavior

2011 ◽  
Vol 197-198 ◽  
pp. 631-634
Author(s):  
Ming Gao ◽  
Yu Qing Yan
Keyword(s):  
Activation Energy ◽  
Thermal Analysis ◽  
Thermal Decomposition ◽  
Thermal Degradation ◽  
Oxygen Index ◽  
Fire Retardant ◽  
Decomposition Temperature ◽  
Degradation Behavior ◽  
Limiting Oxygen Index ◽  
Thermal Degradation Behavior

Cellulose treated with fire retardant was studied by thermogravimetry (TG), differential thermal analysis (DTA) and limiting oxygen index (LOI). The kinetic parameters for the thermal degradation are obtained following the method of Broido. For the fire retardant cellulose, the activation energy and decomposition temperature were much decreased while char yield and LOI were increased. The main thermal decomposition of the samples with higher LOI occurs at lower temperatures, while that with lower LOI occurs at higher temperatures.

Mechanism of Collagen Processed with Urea Determined by Thermal Degradation Analysis*

2020 ◽  
Vol 115 (10) ◽  
pp. 380-389
Author(s):  
Keyong Tang ◽  
Weilin Li ◽  
Jie Liu ◽  
Cheng-Kung Liu ◽  
Hongbo Pan
Keyword(s):  
Activation Energy ◽  
Hydrogen Bonds ◽  
Thermal Degradation ◽  
Collagen Fibers ◽  
Urea Solution ◽  
Collagen Peptides ◽  
Amino Compounds ◽  
Thermal Degradation Behavior ◽  
Degradation Activation Energy ◽  
The Stability

During the beamhouse process for nappa leather, pelts are usually limed with amino compounds such as urea, ethylenediamine, and triethanolamine. However, the interaction between amino compounds and collagen is not well known. In this work, collagen fibers were soaked in various concentrations of urea and the thermal degradation of collagen fibers were studied by the methods Horowitz-Metzger and Coats-Redfern. The mechanism of the reaction between urea and collagen fibers is discussed, wherein the thermal degradation activation energy first decreases and then increases. The lowest thermal degradation activation energy of urea processed collagen appears at 2-3 mol/L urea, suggesting that the stability of collagen is the poorest when the pelt is processed in the urea solution. At the urea concentration above 6 mol/L, the thermal degradation activation energy of the sample is similar to samples without urea processing and the higher concentrations does not have the same effect as lower concentrations of urea. The collagen fibers with a urea processing history were washed to remove the urea in them, and the samples were studied again for their thermal degradation behavior. The results indicated that the thermal degradation activation energy of the collagen fibers might recover to the unprocessed level. Therefore, it was suggested that the reaction between urea molecules and collagen fibers is reversible. Urea molecules might help to destroy some of the hydrogen bonds between collagen peptides in the urea solution. After the urea is washed out, the structure of the collagen will return to its original state, because the hydrogen bonds might be reconstructed

Application of Calculus Equation in Solving Thermal Decomposition Kinetics Parameters of Flame Retardant Wood

2014 ◽  
Vol 983 ◽  
pp. 190-193
Author(s):  
Cai Yun Sun ◽  
Yong Li Yang ◽  
Ming Gao
Keyword(s):  
Activation Energy ◽  
Thermal Decomposition ◽  
Thermal Degradation ◽  
Phosphoric Acid ◽  
Flame Retardant ◽  
Kinetic Parameters ◽  
Flame Retardancy ◽  
Decomposition Kinetics ◽  
Thermal Decomposition Kinetics ◽  
Kinetics Parameters

Wood has been treated with amino resins and amino resins modified with phosphoric acid to impart flame retardancy. The thermal degradation of samples has been studied by thermogravimetry (TG) in air. From the resulting data, kinetic parameters for different stages of thermal degradation are obtained following the method of Broido. For the decomposition of wood and flame retardant wood, the activation energy is found to decrease from 122 to 72 kJmol-1.

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