scholarly journals Devolatilization of African Palm (Elaeis guineensis) Husk studied by TG-MS

2018 ◽  
Vol 38 (2) ◽  
pp. 9-17
Author(s):  
Alberto Ricardo Albis Arrieta ◽  
Ever Ortiz Muñoz ◽  
Ismael Piñeres Ariza ◽  
Andrés Felipe Suárez Escobar ◽  
Marley Cecilia Vanegas Chamorro
Keyword(s):  
Activation Energy ◽  
Thermal Degradation ◽  
Mass Spectroscopy ◽  
Elaeis Guineensis ◽  
Degradation Process ◽  
Pyrolysis Process ◽  
Distributed Activation Energy Model ◽  
Evolved Gas ◽  
Secondary Reactions ◽  
Thermal Degradation Process

 Using simultaneous thermogravimetrical analysis coupled with mass spectroscopy, the pyrolysis of African palm husk, using several heat rates and programs was performed. Seven relations of mass/charge were followed of the evolved gas of the pyrolysis process, fitting the kinetics and the mass spectroscopy signals to the distributed activation energy model (DAEM) with different numbers of pseudo-components. Fitting with four pseudo-components proved to be the best for modeling the thermal degradation process. Kinetic parameters were not affected by the heating rate or program employed, which agrees with other reports for similar biomass. Methane, methanol formaldehyde, furfural were successfully fitted to the DAEM model, nevertheless CO2 and NO2 were not able to be represented by this model due to its production in secondary reactions in gaseous phase.

Non-isothermal degradation kinetics for polycarbonate/ polymethylphenylsilsesquioxane composites

e-Polymers ◽  
2010 ◽  
Vol 10 (1) ◽  
Author(s):  
Jiangbo Wang ◽  
Zhong Xin
Keyword(s):  
Activation Energy ◽  
Thermogravimetric Analysis ◽  
Thermal Degradation ◽  
Flame Retardancy ◽  
Degradation Kinetics ◽  
Degradation Process ◽  
Nitrogen Atmosphere ◽  
Ozawa Method ◽  
Degradation Behaviors ◽  
Thermal Degradation Process

AbstractThe thermal degradation behaviors of PC/PMPSQ (polymethylphenylsilsesquioxane) systems were investigated by thermogravimetric analysis (TGA) under non-isothermal conditions in nitrogen atmosphere. During non-isothermal degradation, Kissinger and Flynn-Wall-Ozawa methods were used to analyze the thermal degradation process. The results showed that a remarkable decrease in activation energy ( E ) was observed in the early and middle stages of thermal degradation in the presence of PMPSQ, which indicated that the addition of PMPSQ promoted the thermal degradation of PC. Flynn-Wall-Ozawa method further revealed that PMPSQ significantly increased the activation energy of PC thermal degradation in the final stage, which illustrated that the PMPSQ stabilized the char residues and improved the flame retardancy of PC in the final period of thermal degradation process

Thermal Stability and Kinetic Analysis of Xanthoceras sorbifolia Polysaccharide

2012 ◽  
Vol 518-523 ◽  
pp. 3904-3907 ◽  
Author(s):  
Quan Cheng Zhou ◽  
Hong Mei Zhang ◽  
De Mao Li
Keyword(s):  
Activation Energy ◽  
Thermal Stability ◽  
Kinetic Model ◽  
Thermal Degradation ◽  
Kinetic Analysis ◽  
Large Scale ◽  
Degradation Process ◽  
Second Step ◽  
Step Process ◽  
Thermal Degradation Process

Pyrolysis and kinetic analysis of Xanthoceras Sorbifolia polysaccharide were evaluated using the TG-DTG/DTA method. The results indicated that its mass loss occured in three-step process . The first step could be attributed to the expulsion of water of crystallization at 25 - 176 °C. The second step corresponded to the large scale degradation of X. Sorbifolia polysaccharide in the temperature range of 179 - 661 °C. The final step was slow degradation of residues. Heating rate had significant effects on the pyrolysis of X. Sorbifolia polysaccharide and nitrogen could improve its stability. A close value of activation energy E of the thermal degradation process has been obtained by FWO, KAS and Popescu methods. The possible kinetic model was estimated to be Jander 5 (g(α)=[1-(1-α)1/3]1/2.

Kinetic study of the stabilizing effect of aluminum trihydroxide on thermal degradation of epoxy resin

e-Polymers ◽  
2014 ◽  
Vol 14 (2) ◽  
pp. 133-137 ◽  
Author(s):  
Jiangbo Wang ◽  
Jialin Fang ◽  
Chengwei Wang ◽  
Yongyou Li ◽  
Mengjiao Huang
Keyword(s):  
Activation Energy ◽  
Thermal Degradation ◽  
Epoxy Resin ◽  
Fire Retardant ◽  
Degradation Process ◽  
Ozawa Method ◽  
Degradation Behaviour ◽  
Stabilizing Effect ◽  
Thermal Degradation Process ◽  
Aluminum Trihydroxide

AbstractThe stabilizing effect of epoxy resin (EP)/aluminum trihydroxide (ATH) was measured by thermogravimetric analysis (TGA) in an N2 flow. The Kissinger and Flynn-Wall-Ozawa methods were used to determine the activation energy of non-isothermal degradation at different stages. The results showed that there was a slight increase in activation energy after ATH was added. It confirms the fire-retardant effect of ATH on the thermal degradation behaviour of pure EP. The Flynn-Wall-Ozawa method showed that flame-retardant ATH remarkably enhanced the activation energy of the thermal degradation process for EP, albeit the conversion rate being only 10%, which demonstrated the stabilization of ATH to the char layer of EP.

Thermal stability of phosphorus-containing epoxy resins by thermogravimetric analysis

2018 ◽  
Vol 26 (7) ◽  
pp. 400-407 ◽  
Author(s):  
Xiaomin Lv ◽  
Jialin Fang ◽  
Jinghan Xie ◽  
Xue Yang ◽  
Jiangbo Wang
Keyword(s):  
Activation Energy ◽  
Thermal Stability ◽  
Thermogravimetric Analysis ◽  
Thermal Degradation ◽  
Early Stage ◽  
Degradation Process ◽  
Nitrogen Atmosphere ◽  
Thermal Stabilities ◽  
Phosphorus Containing ◽  
Thermal Degradation Process

The thermal stabilities of epoxy resin/diethyl bis(2-hydroxyethyl)aminomethylphosphonate (EP/DBAMP) systems were investigated by thermogravimetric analysis (TGA) under non-isothermal conditions in nitrogen atmosphere. Kissinger and Flynn–Wall–Ozawa methods were used to study the thermal degradation process. The results showed a remarkable increase of activation energy ( E) in the presence of DBAMP, which indicated that the addition of DBAMP retarded the thermal degradation of EP. The Flynn–Wall–Ozawa analysis further revealed that DBAMP significantly increased the activation energy in the early stage of EP’s thermal degradation, demonstrating that DBAMP had improved the initial thermal stability and modified the flame retardancy of EP in the thermal degradation process.

scholarly journals Thermal Degradation Characteristics and Kinetics of Oxy Combustion of Corn Residues

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Poramate Sittisun ◽  
Nakorn Tippayawong ◽  
Darunee Wattanasiriwech
Keyword(s):  
Activation Energy ◽  
Thermal Degradation ◽  
Degradation Process ◽  
Similar Magnitude ◽  
Heating Rates ◽  
Decomposition Rates ◽  
Similar Weight ◽  
Thermal Degradation Process ◽  
Kinetics Of ◽  
Corn Residues

Thermogravimetric analysis was used to investigate oxy combustion of corncob and stover. The biomass samples were heated from ambient temperature to 900°C at different heating rates of 10, 30, and 50 K/min. Both biomass samples showed similar weight loss patterns with three zones, corresponding to dehydration, devolatilization, and char combustion, but displayed different degradation temperatures. Increasing heating rate was found to shift the degradation patterns to higher temperatures. Decomposition rates of cob and stover may have been influenced by their lignocellulosic composition. The kinetic parameters of the thermal degradation process were also determined and compared using the Flynn-Wall-Ozawa and Kissinger-Akahira-Sunose methods. Both methods were found to give similar values and patterns of activation energy against conversion fraction. The average values were found to be in similar magnitude to those reported in the literature, around 170 and 148 kJ/mol for cob and stover, respectively.

Structural comparisons of pyrodextrins during thermal degradation process: The role of hydrochloric acid

2021 ◽  
Vol 349 ◽  
pp. 129174
Author(s):  
Huijia Mao ◽  
Zhijun Chen ◽  
Jie Li ◽  
Xueyang Zhai ◽  
Hongyan Li ◽  
...  
Keyword(s):  
Hydrochloric Acid ◽  
Thermal Degradation ◽  
Degradation Process ◽  
Thermal Degradation Process

scholarly journals A thermal degradation study of Y and La methanesulfonates

2006 ◽  
Vol 71 (8-9) ◽  
pp. 905-915
Author(s):  
Moura de ◽  
Jivaldo Matos ◽  
Farias de
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Differential Thermal Analysis ◽  
Thermal Degradation ◽  
Degradation Process ◽  
Oxide Formation ◽  
Scanning Calorimetry ◽  
Degradation Study ◽  
Thermogravimetric Data ◽  
Thermal Degradation Process

The synthesis, characterization and thermal degradation of yttrium and lanthanum methanesulfonates is reported. The prepared salts were characterized by elemental analysis and infrared spectroscopy. The thermal degradation study was performed using thermogravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC).Using the thermogravimetric data, a kinetic study of the dehydration ofY and Lamethanesulfonates was performed employing the Coats-Redfern and Zsak?methods. It was verified that under heating, yttrium and lanthanum methanesulfonates undergo three main processes: dehydration, thermal degradation and oxide formation. Furthermore, depending on the nature of the atmosphere, i.e., inert or oxidant, the thermal degradation process could be endothermic (N2) or exothermic (air).

scholarly journals Thermal degradation of the anthocyanins extracts from jabuticaba peels and red cabbage leaves

2020 ◽  
Vol 16 (6) ◽  
Author(s):  
Priscila Pereira Souza ◽  
Weber Silva Robazza ◽  
Alessandro Cazonatto Galvão
Keyword(s):  
Thermal Degradation ◽  
Degradation Kinetics ◽  
Degradation Process ◽  
Differential Method ◽  
Red Cabbage ◽  
Average Value ◽  
Extraction And Purification ◽  
Different Temperatures ◽  
Thermal Degradation Process ◽  
Experimental Values

Anthocyanins are phenolic compounds with tinctorial capacity. Their successful extraction and purification depends on information associated with their thermal stability. This work presents a study on the degradation kinetics of the anthocyanins in the peels of the jabuticaba fruits and the leaves of red cabbage through assays performed at different temperatures (ranging from 323.15 K to 363.15 K) and degradation times (up to 10 hours for jabuticaba and 30 hours for red cabbage). Total monomeric anthocyanins were determined through the pH differential method. Regarding the extraction, it was observed a larger quantity of anthocyanins from red cabbage extracts, with an average value of 1.3774 mg‧gdb-1, when compared to jabuticaba extracts, with an average value of 1.0479 mg‧gdb-1. The results suggest that the anthocyanins in the red cabbage leaves are much more thermally stable than the anthocyanins in the jabuticaba peels. The experimental assays suggest that the thermal degradation reaction proceeds according to a first-order kinetics model for the anthocyanins in both sources under study. The experimental values were treated according to their thermodynamic relations, which indicated that the thermal degradation process of the evaluated anthocyanins is endothermic and not spontaneous, with similar values of 64.8 kJ‧mol-1 for the red cabbage and 70.2 kJ‧mol-1 for the jabuticaba. 

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