Study on gas desorption and diffusion kinetic behavior in coal matrix using a modified shrinking core model

Following earlier work of Huggins and Nix [Ionics6, 57 (2000)], several recent theoretical studies have used the shrinking core model to predict intraparticle Li concentration profiles and associated stress fields. A goal of such efforts is to understand and predict particle fracture, which is sometimes observed in degraded electrodes. In this paper we present experimental data on LiCoO2 and graphite active particles, consistent with previously published data, showing the presence of numerous internal pores or cracks in both positive and negative active electrode particles. New calculations presented here show that the presence of free surfaces, from even small internal cracks or pores, both quantitatively and qualitatively alters the internal stress distributions such that particles are prone to internal cracking rather than to the surface cracking that had been predicted previously. Thus, the fracture strength of particles depends largely on the internal microstructure of particles, about which little is known, rather than on the intrinsic mechanical properties of the particle materials. The validity of the shrinking core model for explaining either stress maps or transport is questioned for particles with internal structure, which includes most, if not all, secondary electrode particles.

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Correction to An Unreacted Shrinking Core Model Serves for Predicting Combustion Rates of Organic Additives in Clay Bricks

Energy & Fuels ◽

10.1021/acs.energyfuels.1c00307 ◽

2021 ◽

Vol 35 (5) ◽

pp. 4616-4616

Author(s):

Florian Wesenauer ◽

Christian Jordan ◽

Mario Pichler ◽

Aron Frei ◽

Mudassar Azam ◽

...

Keyword(s):

Core Model ◽

Shrinking Core Model ◽

Organic Additives ◽

Clay Bricks ◽

Shrinking Core

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A variable diffusivity shrinking-core model and its application to the direct sulfation of limestone

The Canadian Journal of Chemical Engineering ◽

10.1002/cjce.5450710511 ◽

1993 ◽

Vol 71 (5) ◽

pp. 734-745 ◽

Cited By ~ 32

Author(s):

S. V. Krishnan ◽

Stratis V. Sotirchos

Keyword(s):

Core Model ◽

Shrinking Core Model ◽

Variable Diffusivity ◽

Shrinking Core

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Modified Shrinking Core Model for Atomic Layer Deposition of TiO2on Porous Alumina with Ultrahigh Aspect Ratio

Bulletin of the Korean Chemical Society ◽

10.5012/bkcs.2013.34.2.519 ◽

2013 ◽

Vol 34 (2) ◽

pp. 519-523 ◽

Cited By ~ 3

Author(s):

Inhye Park ◽

Jina Leem ◽

Hoo-Yong Lee ◽

Yo-Sep Min

Keyword(s):

Aspect Ratio ◽

Atomic Layer Deposition ◽

Porous Alumina ◽

Atomic Layer ◽

Core Model ◽

Shrinking Core Model ◽

Layer Deposition ◽

Shrinking Core

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Macerals of Shengli Lignite in Inner Mongolia of China and Their Combustion Reactivity

Journal of Chemistry ◽

10.1155/2016/2513275 ◽

2016 ◽

Vol 2016 ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

Ying Yue Teng ◽

Yu Zhe Liu ◽

Quan Sheng Liu ◽

Chang Qing Li

Keyword(s):

Activation Energy ◽

Homogeneous Model ◽

Optical Microscope ◽

Core Model ◽

Shrinking Core Model ◽

Compact Structure ◽

Shrinking Core ◽

Combustion Reactivity ◽

Combustion Processes ◽

Kinetics Of

The macerals, including fusinitic coal containing 72.20% inertinite and xyloid coal containing 91.43% huminite, were separated from Shengli lignite using an optical microscope, and their combustion reactivity was examined by thermogravimetric analysis. Several combustion parameters, including ignition and burnout indices, were analyzed, and the combustion kinetics of the samples were calculated by regression. Fusinitic coal presented a porous structure, while xyloid coal presented a compact structure. The specific surface area of fusinitic coal was 2.5 times larger than that of xyloid coal, and the light-off temperature of the former was higher than that of the latter. However, the overall combustion reactivity of fusinitic coal was better than that of xyloid coal. The combustion processes of fusinitic and xyloid coals can be accurately described by both the homogeneous model and the shrinking core model. The features of xyloid coal agree with the shrinking core model when its conversion rate is 10%–90%. The activation energy of fusinitic coal during combustion can be divided into three phases, with the middle phase featuring the highest energy. The activation energy of xyloid coal is lower than that of fusinitic coal in the light-off phase, which may explain the low light-off temperature of this coal.

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shrinking core model

Catalysis from A to Z ◽

10.1002/9783527809080.cataz15087 ◽

2020 ◽

Keyword(s):

Core Model ◽

Shrinking Core Model ◽

Shrinking Core

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Kinetic Study in Atmospheric Pressure Organic Acid Leaching: Shrinking Core Model versus Lump Model

Minerals ◽

10.3390/min10070613 ◽

2020 ◽

Vol 10 (7) ◽

pp. 613

Author(s):

Kevin Cleary Wanta ◽

Widi Astuti ◽

Indra Perdana ◽

Himawan Tri Bayu Murti Petrus

Keyword(s):

Citric Acid ◽

Acid Solution ◽

Acid Leaching ◽

Core Model ◽

Shrinking Core Model ◽

Citric Acid Solution ◽

Lumped Model ◽

Leaching Process ◽

Shrinking Core ◽

Simulation Results

The kinetics study has an essential role in the scale-up process because it illustrates the real phenomena of a process. This study aims to develop a mathematical model that can explain the mechanism of the leaching process of laterite ore using a low concentration of the citric acid solution and evaluate that model using the experimental data. As a raw material, this process used powder-shaped limonite laterite ores with a size of 125–150 µm. The leaching process is carried out using 0.1 M citric acid solution, F:S ratio of 1:20, and a leaching time of 2 h. The temperature parameter was varied at 303, 333, and 358 K. The experimental results showed that the higher the operating temperature, the higher the extracted nickel. The results of this experiment were used to evaluate the shrinking core kinetics model and the lumped model. The simulation results for both models show that the lumped model can provide better simulation results. Quantitatively, the percentage of errors from the shrinking core model is around 3.5 times greater than the percentage of errors from using the lumped model. This result shows that in this leaching process, the process mechanism that occurs involves the reactant diffusion step and the chemical reactions step; those steps run simultaneously.

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