scholarly journals Multistage kinetic analysis of DMAA/MBAM polymer removal from gelcast ceramic parts using a multi-stage parallel reaction model and model-free method

RSC Advances ◽  
2019 ◽  
Vol 9 (47) ◽  
pp. 27305-27317 ◽  
Author(s):  
Jing Li ◽  
Jindi Huang ◽  
Ruiming Yin
Keyword(s):  
Kinetic Analysis ◽  
Reaction Mechanisms ◽  
Reaction Model ◽  
Parallel Reaction ◽  
Model Free ◽  
Multi Stage

This work aims to develop an effective method to investigate the multistage debinding kinetics and the reaction mechanisms of removing DMAA/MBAM polymer from gelcast ceramic parts.

scholarly journals Kinetic Analysis of the Thermal Degradation of Recycled Acrylonitrile-Butadiene-Styrene by non-Isothermal Thermogravimetry

Polymers ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 281 ◽  
Author(s):  
Rafael Balart ◽  
David Garcia-Sanoguera ◽  
Luis Quiles-Carrillo ◽  
Nestor Montanes ◽  
Sergio Torres-Giner
Keyword(s):  
Thermal Degradation ◽  
Kinetic Analysis ◽  
Acrylonitrile Butadiene Styrene ◽  
Isoconversional Methods ◽  
Reaction Model ◽  
Integral Model ◽  
Heating Rates ◽  
Exponential Factor ◽  
Model Free ◽  
Butadiene Styrene

This work presents an in-depth kinetic study of the thermal degradation of recycled acrylonitrile-butadiene-styrene (ABS) polymer. Non-isothermal thermogravimetric analysis (TGA) data in nitrogen atmosphere at different heating rates comprised between 2 and 30 K min−1 were used to obtain the apparent activation energy (Ea) of the thermal degradation process of ABS by isoconversional (differential and integral) model-free methods. Among others, the differential Friedman method was used. Regarding integral methods, several methods with different approximations of the temperature integral were used, which gave different accuracies in Ea. In particular, the Flynn-Wall-Ozawa (FWO), the Kissinger-Akahira-Sunose (KAS), and the Starink methods were used. The results obtained by these methods were compared to the Kissinger method based on peak temperature (Tm) measurements at the maximum degradation rate. Combined Kinetic Analysis (CKA) was also carried out by using a modified expression derived from the general Sestak-Berggren equation with excellent results compared with the previous methods. Isoconversional methods revealed negligible variation of Ea with the conversion. Furthermore, the reaction model was assessed by calculating the characteristic and functions and comparing them with some master plots, resulting in a nth order reaction model with n = 1.4950, which allowed calculating the pre-exponential factor (A) of the Arrhenius constant. The results showed that Ea of the thermal degradation of ABS was 163.3 kJ mol−1, while ln A was 27.5410 (A in min−1). The predicted values obtained by integration of the general kinetic expression with the calculated kinetic triplet were in full agreement with the experimental data, thus giving evidence of the accuracy of the obtained kinetic parameters.

Kinetic study of Huadian oil shale combustion using a multi-stage parallel reaction model

Energy ◽  
2015 ◽  
Vol 82 ◽  
pp. 705-713 ◽  
Author(s):  
Youhong Sun ◽  
Fengtian Bai ◽  
Xiaoshu Lü ◽  
Chunxia Jia ◽  
Qing Wang ◽  
...  
Keyword(s):  
Kinetic Study ◽  
Oil Shale ◽  
Reaction Model ◽  
Parallel Reaction ◽  
Multi Stage

scholarly journals Kinetic Analysis of Pyrolysis and Thermo-Oxidative Decomposition of Tennis String Nylon Wastes

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7564
Author(s):  
Haibo Wan ◽  
Zhen Huang
Keyword(s):  
Thermal Degradation ◽  
Kinetic Analysis ◽  
Model Fitting ◽  
Degradation Process ◽  
Nylon 6 ◽  
Reaction Model ◽  
Heating Rates ◽  
Model Free ◽  
Order Chemical Reaction ◽  
First Order Chemical Reaction

Thermal degradation of nylon-6 tennis string nylon wastes in inert nitrogen and air atmospheres was investigated by means of multiple heating-rate thermogravimetric analyses. The results obtained under the heating rates of 5–20 K/min are compared in terms of degradation feature and specific temperature for two atmospheres. Using nonisothermal data, kinetic analysis was thoroughly conducted using various isoconversional model-free methods, including Starink, Madhusudanan–Krishnan–Ninan, Tang, Coats–Redfern, and Flynn–Wall–Ozawa methods. With these kinetic analysis methods, the activation energy over the entire degradation process was successfully calculated. By means of the model-fitting master-plots method, the first-order chemical reaction model was determined to be the most appropriate mechanism function for describing pyrolysis and oxidative thermal degradation of nylon-6 waste. Using kinetic parameters, satisfactory matching against experimental data resulted using the Coats–Redfern method for both cases. Furthermore, thermodynamic parameters such as changes in entropy, enthalpy, and Gibbs free energy during thermal degradation processes were evaluated.

The Kinetic Analysis of Biomass Burning Based on Two-Component Reaction Model

2012 ◽  
Vol 424-425 ◽  
pp. 1301-1304
Author(s):  
Hong Bo Lu ◽  
Ze Hui Wang ◽  
Yu Xin Ma
Keyword(s):  
Kinetic Analysis ◽  
Heating Rate ◽  
Biomass Burning ◽  
Combustion Process ◽  
Reaction Model ◽  
Experimental Results ◽  
Parallel Reaction ◽  
Heating Rates ◽  
Two Component ◽  
Good Agreement

Combustion of sawdust was studied using Pyris-1TGA thermogravimetric apparatus in the heating rates of 20, 40, 60K/min. The combustion process of sawdust includes three steps: losing water, precipitation and combustion of volatile, and carburization. A bicomponent parallel reaction model is created and used to simulate the combustion process of sawdust under the heating rate of 40K/min. Comparison of simulation and experimental results shows that the fitting curves are in good agreement with the experimental results

Investigation of non-isothermal pyrolysis kinetics of waste industrial hemp stem by three-parallel-reaction model

2021 ◽  
pp. 126402
Author(s):  
Fangjun Chen ◽  
Fengxia Zhang ◽  
Shiliang Yang ◽  
Huili Liu ◽  
Hua Wang ◽  
...  
Keyword(s):  
Reaction Model ◽  
Parallel Reaction ◽  
Pyrolysis Kinetics ◽  
Industrial Hemp ◽  
Kinetics Of

A test of the parallel reaction model using kinetic measurements on hydrous pyrolysis residues

1995 ◽  
Vol 23 (10) ◽  
pp. 931-939 ◽  
Author(s):  
Alan K. Burnham ◽  
Birthe J. Schmidt ◽  
Robert L. Braun
Keyword(s):  
Reaction Model ◽  
Parallel Reaction ◽  
Kinetic Measurements ◽  
Hydrous Pyrolysis
Sign in / Sign up

Export Citation Format

Share Document