Physicochemical Characterization and Pyrolysis Kinetic Study of Sugarcane Bagasse Using Thermogravimetric Analysis

2016 ◽  
Vol 138 (5) ◽  
Author(s):  
Anil Kumar Varma ◽  
Prasenjit Mondal

The present study was conducted to investigate the physicochemical properties and pyrolysis kinetics of sugarcane bagasse (SB). The physiochemical properties of SB were determined to examine its potential for pyrolysis. The physiochemical properties such as proximate analysis, ultimate analysis, heating values, lignocellulosic composition, X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) of SB were investigated. The pyrolysis experiments were conducted in a nonisothermal thermogravimetric analyzer (TGA) to understand the thermal degradation behavior of SB. The activation energy (Ea) of SB pyrolysis was calculated by model-free Kissinger–Akahira–Sunose (KAS) and Ozawa–Flynn–Wall (OFW) methods. Average values of activation energy determined through KAS and OFW methods are found as 91.64 kJ/mol and 104.43 kJ/mol, respectively. Variation in the activation energy with degree of conversion was observed, which shows that pyrolysis is a complex process composed of several reactions. Coats–Redfern method was used to calculate the pre-exponential factor and reaction order. Conversion of SB due to heat treatment computed by using the kinetic parameters is found to be in good agreement with the experimental conversion data, and the maximum error limit between the experimental and predicted conversions is 8.5% for 5 °C/min, 6.0% for 10 °C/min, and 11.6% for 20 °C/min. The current investigation proves the suitability of SB as a potential feedstock for pyrolysis.

2010 ◽  
Vol 660-661 ◽  
pp. 593-598 ◽  
Author(s):  
Kássia Graciele dos Santos ◽  
Taisa S. Lira ◽  
Valéria V. Murata ◽  
Marco Gianesella ◽  
Marcos A.S. Barrozo

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.


2018 ◽  
Vol 28 ◽  
pp. 75-89
Author(s):  
Hamid Reza Javadinejad ◽  
Sayed Ahmad Hosseini ◽  
Mohsen Saboktakin Rizi ◽  
Eiman Aghababaei ◽  
Hossein Naseri

The kinetic study for the synthesis of Fluorapatite has been done using the thermogravimetric technique under non-isothermal conditions and at four heating rates of 5, 10, 15 and 20 °C. Both model free and model-fitting methods were used to investigate kinetic parameters. Calcium oxide, phosphorus pentoxide and calcium fluoride were used as the precursor materials. The activation energy values were calculated through model-fitting and isoconversional methods and were used to predict the reaction model and pre-exponential factor. In this case several techniques were considered such as master plots and compensation effects. The results indicated that the reaction mechanism was chemically controlled with second and third order reaction models in the whole range of conversion which the activation energy varied from 25 to 43 kJ/mol.


2014 ◽  
Vol 18 (3) ◽  
pp. 833-842 ◽  
Author(s):  
Esin Apaydin-Varol ◽  
Sevgi Polat ◽  
Ayse Putun

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.


2014 ◽  
Vol 960-961 ◽  
pp. 442-446
Author(s):  
Lin Chen ◽  
Shu Zhong Wang ◽  
Zhi Qiang Wu ◽  
Hai Yu Meng ◽  
Jun Zhao

Wood-based materials from Municipal Solid Waste have the potential of covering a significant part of the future demand on gasification capacities. However, their pyrolysis kinetics and gasification behavior has not yet been fully investigated. This paper describes the pyrolysis characteristics of typing paper and Chinese parasol from municipal solid waste applying the non-isothermal thermogravimetric analysis, the apparent activation energy and the pre-exponential factor were obtained by kinetics analysis at the heating rate of 10/20/40 oC•min-1.


2021 ◽  
Vol 3 (3) ◽  
Author(s):  
Christiano Bruneli Peres ◽  
André Henrique Rosa ◽  
Leandro Cardoso de Morais

AbstractBiomass is considering a source of organic carbon, which can replace fossil resources by using pyrolysis process, therefore an efficient biomass thermal modification technology has been target of so much research. The objective of this work is to study the potential energy of sugarcane bagasse and thermochemically modified bagasse for bioenergy potential for use in heat generation and energy. The thermal analysis was conducted by powder-shaped exposure of the three study samples (SB, AC-1, and AC-2) at three heating rates of (5, 7.5 and 10 °C min−1), it was possible to identify three stages of thermal degradation and study some thermochemical reactions, using two iso-conversional models, Kissinger–Akahira–Sunose (KAS) and Ozawa–Flynn–Wall (OFW) to calculate some kinetic parameters, such as activation energy (Ea) and pre-exponential factor (A). First step was about the devolatilization of volatile matter, moisture, and other substances. Degradation of hemicellulose, cellulose and lignin were shown in a second step. Characterization analyzes, such as SEM–EDX and textural parameters of the samples, show the presence of carbon in samples SB and AC-1. Due to SEM analyzes, morphological differences between the samples are showing as AC-1 and AC-2 samples present a rougher shape with pores, on the other hand, SB sample show a fibrous shape. In conclusion, sugarcane bagasse and thermochemically modified bagasse, show very promising results, for future studies, such as for bioenergy potential.


Author(s):  
Somayeh Ebrahimi ◽  
Jafarsadegh Moghaddas

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.


2020 ◽  
Vol 11 (4) ◽  
pp. 11357-11379

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.


Energies ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3977
Author(s):  
Magdalena Matusiak ◽  
Radosław Ślęzak ◽  
Stanisław Ledakowicz

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.


2020 ◽  
Vol 7 (4) ◽  
pp. 807-815 ◽  
Author(s):  
Bothwell Nyoni ◽  
Sifundo Duma ◽  
Lukanyo Bolo ◽  
Shaka Shabangu ◽  
Shanganyane P. Hlangothi

AbstractIn this work, the co-pyrolysis of coal and algae is explored with special emphasis on decomposition kinetics and the possibility of the existence of synergistic effects. Modelling and kinetics analysis based approaches were used for the investigation of the existence of synergistic effects. The co-pyrolysis kinetics was studied using the model-free, Coats–Redfern integral method. The kinetics were evaluated for 1st and 2nd order reaction models. Results reveal that Scenedesmus microalgae is characterised by a two stage decomposition process that occurs at temperature ranges of 200–400 °C and 500–700 °C with activation energy of 145.5 and 127.3 kJ/mol, respectively. Bituminous coal has a two stage, slow decomposition process that occurs at temperature ranges of 400–700 °C and above 750 °C with an activation energy of 81.8 and 649.3 kJ/mol, respectively. Furthermore, co-pyrolysis of coal and microalgae is characterised by three stages whose kinetics are dominated by the pyrolysis of the individual materials. For the studied range of coal/algae ratios, the three pyrolysis stages occur in the approximate temperature ranges of 200–400 °C, 430–650 °C and above 750 °C, with activation energies in the ranges of 131–138, 72–78 and 864.5–1235 kJ/mol, respectively. Modelling and kinetics study showed that there is strong evidence of interactions between coal and microalgae that manifest as synergistic effects especially in the second and third stages of decomposition.


2019 ◽  
Vol 33 (7) ◽  
pp. 956-966
Author(s):  
Hamidreza Azimi ◽  
Pardis Abedifard

The objective of this study was to clarify the mechanical properties and the non-isothermal degradation kinetics of Polyamide 66 (PA 66)/glass fiber (GF) composites. The non-isothermal degradation behavior of the samples was studied by thermal gravimetric analysis under nitrogen purge. The perfect compatibility of GFs with polymer matrix in composites was studied by scanning electron microscopy. It was found that with increasing content of GFs in samples due to good distribution of fibers in PA 66, the degradation temperature and calculated activation energy in composites increased in all heating rates. The activation energy was calculated by the Flynn–Wall–Ozawa method (isoconversional method). It was concluded that the model-free methods can be a reliable way to determine the kinetic parameters. Furthermore, the isokinetic relationship was used to estimate a model-independent pre-exponential factor (ln A) corresponding to a given degree of conversion.


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