Approximation-based integral versus differential isoconversional approaches to the evaluation of kinetic parameters from thermogravimetry

Neglur, R.; Grooff, D.; Hosten, Eric C.; Aucamp, Marique; Liebenberg, Wilna

doi:10.1007/s10973-016-5244-x

Cited by 9 publications

(5 citation statements)

References 24 publications

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“…If we refer to the literature, one can observe that the activation energy seems to increase with the dehydration temperature. Independently of the degree of hydration, for a dehydration temperature close to 90 • C, an activation energy value can be expected around one hundred kilojoules per mole of compound [15][16][17], somewhat higher than our value.…”

Section: Thermal Behavior Of Prednisolone Sesquihydrate During Dehydr...contrasting

confidence: 77%

Evidence of a New Crystalline Phase of Prednisolone Obtained from the Study of the Hydration–Dehydration Mechanisms of the Sesquihydrate

et al. 2023

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The dehydration of prednisolone sesquihydrate is studied and characterized by different physico-chemical analysis methods. The meticulous study of this dehydration led to the highlighting of a new solid form (form 3), metastable, never identified before. In a second step, the rehydration of anhydrous forms 1 and 2 of prednisolone is studied, in particular by Dynamic Vapor Sorption. It is then demonstrated that neither of the two forms is sensitive to humidity. By means of solid-gas equilibria, the sesquihydrate can only be obtainable from the isomorphic anhydrous form. Finally, a classification of the sesquihydrate is made, taking into account, in particular, the activation energy determined during dehydration.

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Section: Thermal Behavior Of Prednisolone Sesquihydrate During Dehydr...contrasting

confidence: 77%

Evidence of a New Crystalline Phase of Prednisolone Obtained from the Study of the Hydration–Dehydration Mechanisms of the Sesquihydrate

et al. 2023

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“…Reich and Levi [14] made mistakes since they did not recognize that it is a transcendental function. Although different efforts have been made to solve this puzzle over the past six decades [15][16][17][18][19][20][21][22][23][24][25][26][27][28], troubles still occasionally arise since 'there is no true value for the integral', as stated by Tang [27]. The temperature integral has been playing an 'enigmatic' role in non-isothermal kinetic analysis.…”

Section: Introductionmentioning

confidence: 99%

“…In the other words, it is exactly the famous Coats-Redfern method [12]. In addition to the truncations, some modified approximations were also proposed to improve the calculation precision [8,[17][18][19][20][26][27][28].…”

Section: Introductionmentioning

confidence: 99%

Numerical Calculation and 3-D Imaging of the Arrhenius Temperature Integral

Zhang,

Zheng,

et al. 2023

Separations

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The Arrhenius temperature integral is typically used in non-isothermal kinetic analysis, which is widely applied in gas–solid reactions in separation processes. In previous studies, researchers provided various methods to solve the temperature integral, but the error usually became significant when the value of x (x = Ea/RT) was too large or too small. In this paper, we present a new series method and design a computer program to calculate the temperature integral. According to the precise calculation of the temperature integral, we first reveal the relationship among the integral, the temperature, and the activation energy, and we find an interesting phenomenon in which the 3-D image of the temperature integral is of self-similarity according to fractal theory. The work is useful for mechanism and theoretical studies of non-isothermal kinetics.

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“…Reich and Levi [14] made mistakes since they didn't recognize it is a transcendental function. Although different efforts have been made for solving this puzzle during the past six decades [15][16][17][18][19][20][21][22][23][24][25][26][27][28], troubles still exist occasionally since 'there is no true value for the integral' [27]. The temperature integral has been playing an 'enigmatic' role in the kinetic analysis.…”

Section: Introductionmentioning

confidence: 99%

“…On the other hand, the complex and simple approximations were preferred and truncated from these series solutions. Besides the truncations, some modified approximations were also proposed [17][18][19][20][26][27][28]31].…”

Section: Introductionmentioning

confidence: 99%

The 3-D Image of The Temperature Integral And Its Self-Similarity

Zhang

et al. 2021

Preprint

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How to derive the accurate value of temperature integral is a vital problem for the non-isothermal kinetic analysis. In the past six decades, researchers provided various methods to solve above problem, but the error usually becomes divergent when the value of x (x=Ea/RT) is too small or too large, no matter whether it is a numerical method or an approximation method. In this paper, we present a new series method and elaborately design a computer program to calculate the value of temperature integral. Finally, we reveal the mysterious relationship between the integral, the temperature and the activation energy, and we find an extremely interesting phenomenon that the 3-D image of the temperature integral is of self-similarity according to the fractal theory.

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Approximation-based integral versus differential isoconversional approaches to the evaluation of kinetic parameters from thermogravimetry

Cited by 9 publications

References 24 publications

Evidence of a New Crystalline Phase of Prednisolone Obtained from the Study of the Hydration–Dehydration Mechanisms of the Sesquihydrate

Evidence of a New Crystalline Phase of Prednisolone Obtained from the Study of the Hydration–Dehydration Mechanisms of the Sesquihydrate

Numerical Calculation and 3-D Imaging of the Arrhenius Temperature Integral

The 3-D Image of The Temperature Integral And Its Self-Similarity

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