Pyrolytic Characteristics and Kinetic Parameters Evaluation of Cassava Stalks Using Thermogravimetric Analyzer

2020 ◽  
Vol 851 ◽  
pp. 137-141
Author(s):  
Sukarni Sukarni ◽  
M. Rifqi Ramadhan
Keyword(s):  
Reaction Order ◽  
Frequency Factor ◽  
Differential Method ◽  
Nitrogen Flow ◽  
Nitrogen Flow Rate ◽  
Kinetic Evaluation ◽  
Thermogravimetric Analyzer ◽  
Second Stage ◽  
Factor Log ◽  
Kinetics Of

Pyrolytic characteristics and kinetics of cassava stalks as a renewable energy source were delved via a thermogravimetric (TG) analyzer. About 10 mg powder of the sample was heated up in the TG cavity under inert conditions with 50 ml.min-1 nitrogen flow rate and operated at 20 °C min-1 of heating program. The pyrolysis process of cassava stalks was taken place into three main stages, in which the peak reaction occurred at the second stage with 70% of the mass was degraded. The differential method of Arrhenius kinetic evaluation resulted in the values of reaction order (n) that was 0.99, activation energy that was 89.46 kJ/mol and logarithmic frequency factor (log A) was 7.7 min-1.

Arrhenius Kinetic Analysis during Combustion of Spirulina platensis Microalgae

2020 ◽  
Vol 851 ◽  
pp. 142-148
Author(s):  
Sukarni Sukarni ◽  
Muklisul Anwar
Keyword(s):  
Spirulina Platensis ◽  
Volatile Matter ◽  
Differential Method ◽  
Air Flow Rate ◽  
Kinetic Evaluation ◽  
Exponential Factor ◽  
Kinetic And Thermodynamic Parameters ◽  
Second Stage ◽  
Factor Log ◽  
Three Stages

Characteristics and potential of microalgae Spirulina platensis as an energy source were studied in regard to the decomposition patterns, as well as kinetic and thermodynamic parameters. The thermogravimetric analysis was performed using the TGA instrument (Mettler Toledo TG DSC 1) at a heating rate of 30 °C/min, with an atmospheric air flow-rate of 100 ml/min at the temperature range of 25-1000 °C. The kinetic was evaluated using a differential method of Arrhenius. The results showed that Spirulina platensis microalgae decomposed into three stages. The first stage is related to the evaporation of moisture, the second stage is associated with the release of volatile matter, and the final stage is the combustion stage of char. The kinetic evaluation resulted in the respective activation energy (), pre-exponential factor (log A) and reaction order (n) are 53.57 kJ/mol, 4.4 min-1, and 1.73. It also understands from the thermodynamic analysis that the respective values of enthalpy (), Gibbs free energy ( and the entropies ( were 48.50 kJ/mol, 146,73 kJ/mol, and-174,78 J/mol.

Pyrolysis Characteristics and Kinetics of Low Rank Coal

2011 ◽  
Vol 695 ◽  
pp. 493-496 ◽  
Author(s):  
Yong Hui Song ◽  
Jian Mei She ◽  
Xin Zhe Lan ◽  
Jun Zhou
Keyword(s):  
Weight Loss ◽  
Heating Rate ◽  
Frequency Factor ◽  
Low Rank ◽  
Coal Pyrolysis ◽  
Pyrolysis Characteristics ◽  
Second Stage ◽  
Thermo Gravimetric Analyzer ◽  
Kinetics Of ◽  
Pyrolysis Kinetic

The pyrolysis characteristics of Jianfanggou(JFG) coal was studied using a thermo-gravimetric analyzer and the pyrolysis kinetic parameters were calculated at the different heating rate. The results showed the DTG curves under different heating rate had three peaks and the corresponding temperature were 100°C, 470°C and 750°C, the pyrolysis process can be divided into three stages conclusively. The maximum weight loss rate at 470°C indicated the major weight loss occurred in the second stage. The Tb, Tf and T∞ obtained under experiment situation. The results of the JFG coal pyrolysis kinetic showed the Tb, Tf and T∞ increased gradually with the accretion of the heating rate. In the meantime, the variation of frequency factor was consistent with the trend of activation energy.

Thermal Characteristic of Tetraselmis chuii Combustion Influenced by Titanium Dioxide (TiO2) Nanoparticle

2020 ◽  
Vol 851 ◽  
pp. 149-155
Author(s):  
Sukarni Sukarni ◽  
Ardianto Prasetiyo ◽  
Retno Wulandari ◽  
Aloon Eko Widiono ◽  
Poppy Puspitasari
Keyword(s):  
Titanium Dioxide ◽  
Reaction Order ◽  
Thermal Characteristic ◽  
Combustion Process ◽  
Differential Method ◽  
Exponential Factor ◽  
Atmospheric Air ◽  
Central Java ◽  
Tetraselmis Chuii ◽  
Factor Log

The investigation of Titanium dioxide (TiO2) nanoparticles on the thermal characteristic of Tetraselmis chuii (T.Chuii) microalgae during combustion process has been carried out through a thermogravimetric (TG) analyzer. T.Chuii microalgae samples were cultured within 8 days at BBPBAP Jepara, Central Java, Indonesia. The microalgae sediment was dried at 80°C for 24 hours then was powdered by means of a mortar. Thereafter, the dried powder of microalgae was filtered with a size of 60 mesh. Titanium dioxide (TiO2) nanoparticles were used as catalysts with the particle size of < 25 nm; these were obtained from Singapore’s Sigma Aldrich. Amount of 0.03 mg of TiO2 and 10 mg of T.Chuii microalgae were mixed mechanically using a mortar to guarantee the homogeneous blend, and then this sample was heated up in the oven for 14 hours at 80°C. The TG experiment was performed at a temperature range 25 to 900°C with atmospheric air at a flow rate of 50 mL/min and a heating rate of 15 °C/min. Differential method of Arrhenius is applied to evaluate kinetic parameters, including reaction order (n), activation energy (Ea), and pre-exponential factor (log A) that were 0.9; 74,191 kJ/mol and 6.38 min-1 for the stage II and 0.87; 118.47 kJ/mol and 7.29 min-1 for stage V.

Kinetics of pyrolysis and properties of carbon black from a scrap tire

2006 ◽  
Vol 60 (6) ◽  
Author(s):  
Z. Koreňová ◽  
M. Juma ◽  
J. Annus ◽  
J. Markoš ◽  
L’. Jelemenský
Keyword(s):  
Carbon Black ◽  
Pore Size ◽  
Rubber Particle ◽  
Ash Content ◽  
Process Conditions ◽  
Nitrogen Flow ◽  
Scrap Tire ◽  
Second Stage ◽  
Wide Range ◽  
Kinetics Of

AbstractThe pyrolysis of rubber from the sidewall and tread of a passenger car tire was carried out in a nitrogen flow at a wide range of final temperatures. Derivative thermogravimetric analysis (DTG) was applied to examine the kinetics at the different process conditions of completed pyrolysis. Two characteristic stages were observed in the DTG curves. The first stage corresponded to the decomposition of processing oil, plastifier, and additives, whereas the rubber polymer was decomposed in the second stage. Several properties of the carbon black formed by the pyrolysis such as ash content, specific surface area, and pore size distribution were determined. A change of the internal structure of the rubber particle in the meso-and macroregions of the pore size was observed.

The Kinetics of Oxygen Delignification of Reed Kraft Pulp (I)-Kinetics of Delignification

2011 ◽  
Vol 236-238 ◽  
pp. 1420-1424
Author(s):  
Xiao Feng Pan ◽  
Le Fan Ma ◽  
Qin Qin Qu ◽  
Jia Liang Lan ◽  
Li Hong Tan
Keyword(s):  
Activation Energy ◽  
Reaction Time ◽  
Oxygen Pressure ◽  
Kraft Pulp ◽  
Reaction Order ◽  
Frequency Factor ◽  
Kappa Number ◽  
Alkali Concentration ◽  
Oxygen Delignification ◽  
Kinetics Of

The kinetics of reed kraft pulp oxygen delignification process is studied, suitable kinetics model determined is -dk/dt=Aexp(-E/RT) [OH-]b[PO2]cKa, and the parameters in the model is calculated. The function for estimation of the kappa number at different reaction time is established for the reed kraft pulp oxygen delignification process. The reaction order fitted is 6.72 for delignification (a), 0.87 for alkali concentration (b), and 0.62 for oxygen pressure(c), respectively. The activation energy E is 80.96KJ/mol and frequency factor A 1.5×104.

Study on the Kinetics of Wet Flue Gas Desulfurization by Carbide Slag

2011 ◽  
Vol 322 ◽  
pp. 252-255
Author(s):  
Sheng Yu Liu ◽  
Li Chao Nengzi ◽  
Cheng Wei Lu ◽  
Wei Qiu ◽  
Yun Ming Hu
Keyword(s):  
Activation Energy ◽  
Chemical Reaction ◽  
Flue Gas ◽  
Reaction Order ◽  
Frequency Factor ◽  
Reaction Model ◽  
Flue Gas Desulfurization ◽  
Economic Costs ◽  
Carbide Slag ◽  
Kinetics Of

Current industrial desulfurization processes involve in economic costs, if carbide slag can be used in those processes, the costs will be reduced and the goal treating waste with waste can be achieved. A mathematic reaction model was built based on the chemical reaction of desulfurization by carbide slag, the overall reaction order n=α+β=1.74, the activation energy Ea=21749.56173J/mol and the frequency factor k0=0.349533643 .

scholarly journals Decomposition Characteristics and Kinetics of Microalgae in N2 and CO2 Atmospheres by a Thermogravimetry

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Xu Qing ◽  
Ma Xiaoqian ◽  
Yu Zhaosheng ◽  
Cai Zilin ◽  
Ling Changming
Keyword(s):  
Activation Energy ◽  
Thermogravimetric Analysis ◽  
Thermal Degradation ◽  
Apparent Activation Energy ◽  
Kinetic Parameters ◽  
Reaction Order ◽  
Heating Rates ◽  
Residual Mass ◽  
Second Stage ◽  
Kinetics Of

The thermal degradation characteristics of microalgae were investigated in highly purified N2 and CO2 atmospheres by a thermogravimetric analysis (TGA) under different heating rates (10, 20, and 40°C/min). The results indicated that the total residual mass in CO2 atmosphere (16.86%) was less than in N2 atmosphere (23.12%); in addition, the kinetics of microalgae in N2 and CO2 atmospheres could be described by the pseudo bicomponent separated state model (PBSM) and pseudo-multi-component overall model (PMOM), respectively. The kinetic parameters calculated by Coats-Redfern method showed that, in CO2 atmosphere, the apparent activation energy (E) of microalgae was between 9.863 and 309.381 kJ mol−1 and the reaction order (n) was varied from 1.1 to 7. The kinetic parameters (E,n) of the second stage in CO2 atmosphere were quite similar to those in N2 atmosphere.

Kinetics and Thermodynamic Data for the Hydrogen Fluoride Addition to Vinyl Fluoride

1971 ◽  
Vol 49 (15) ◽  
pp. 2471-2475
Author(s):  
Leonard O. Moore
Keyword(s):  
Hydrogen Fluoride ◽  
Equilibrium Constants ◽  
Frequency Factor ◽  
Vinyl Fluoride ◽  
A Value ◽  
Reaction Data ◽  
Factor Log ◽  
Kinetics Of ◽  
Fluoride Addition ◽  
Kinetics And Thermodynamic

The kinetics of the addition of hydrogen fluoride to vinyl fluoride have been measured in the vapor phase at temperatures of 100 and 150 °C and under pressures of 170, 308, and 446 N/m2. The rate equation was found to be a typical second order expression, −dx/dt = k [CHF=CH2] [HF]. The energy of activation was calculated to be 17 ± 2 kcal/mol, and the frequency factor, log A (l/mol s) was 6 ± 1. Based on reaction data from the literature, equilibrium constants and a value for ΔH298 were calculated. For this reaction, ΔH298 is about −12 kcal/mol.

Pyrolysis of brown algae (Bifurcaria Bifurcata) in a stainless steel tubular reactor: From a review to a case study

2018 ◽  
Vol 14 (1) ◽  
pp. 31-60 ◽  
Author(s):  
M. Y. Guida ◽  
F. E. Laghchioua ◽  
A. Hannioui
Keyword(s):  
Particle Size ◽  
Stainless Steel ◽  
Flow Rate ◽  
Brown Algae ◽  
Tubular Reactor ◽  
Nitrogen Flow ◽  
Nitrogen Flow Rate ◽  
Bifurcaria Bifurcata ◽  
Bio Oil

This article deals with fast pyrolysis of brown algae, such as Bifurcaria Bifurcata at the range of temperature 300–800 °C in a stainless steel tubular reactor. After a literature review on algae and its importance in renewable sector, a case study was done on pyrolysis of brown algae especially, Bifurcaria Bifurcata. The aim was to experimentally investigate how the temperature, the particle size, the nitrogen flow rate (N2) and the heating rate affect bio-oil, bio-char and gaseous products. These parameters were varied in the ranges of 5–50 °C/min, below 0.2–1 mm and 20–200 mL. min–1, respectively. The maximum bio-oil yield of 41.3wt% was obtained at a pyrolysis temperature of 600 °C, particle size between 0.2–0.5 mm, nitrogen flow rate (N2) of 100 mL. min–1 and heating rate of 5 °C/min. Liquid product obtained under the most suitable and optimal condition was characterized by elemental analysis, 1H-NMR, FT-IR and GC-MS. The analysis of bio-oil showed that bio-oil from Bifurcaria Bifurcata could be a potential source of renewable fuel production and value added chemicals.

The effect of electrondonors on the polymerization kinetics of isoprene

1980 ◽  
Vol 45 (12) ◽  
pp. 3338-3346
Author(s):  
Miroslav Kašpar ◽  
Jiří Trekoval
Keyword(s):  
Induction Period ◽  
Ethyl Ether ◽  
Reaction Order ◽  
Propagation Rate ◽  
Reaction Scheme ◽  
Polymerization Kinetics ◽  
Polymerization Rate ◽  
Constant Concentration ◽  
Initial Concentration ◽  
Kinetics Of

The effect of small additions of 1-octene, butyl ethyl ether and triethylamine on the polymerization kinetics of isoprene (2-methyl-1,3-butadiene) in benzene initiated with butyllithium was investigated by employing the GLC analysis. The addition of 1-octane was reflected only in a shorter induction period of the reaction; the effect on the propagation rate was insignificant. With the increasing amount of butyl ethyl ether, the polymerization rate increases linearly, while the reaction order with respect to the concentration of triethylamine is variable and increases from 0.33 to 0.66 with the increasing concentration of the initiator. For a constant concentration of triethylamine, the reaction order with respect to the initial concentration of the initiator was found to vary considerably, reaching even negative values. A reaction scheme was suggested, taking into account the competition between two different solvates of alkyllithium.

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