Application of the Flash DSC 1 and 2+ for vapor pressure determination above solids and liquids

Buzyurov, Aleksey V.; Nagrimanov, Ruslan N.; Zaitsau, Dzmitry H.; Mukhametzyanov, Timur A.; Abdelaziz, Amir; Solomonov, Boris N.; Schick, Christoph

doi:10.1016/j.tca.2021.179067

Cited by 18 publications

(35 citation statements)

References 79 publications

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“…Experimental determinations were made within the 131–211 °C temperature range for caffeine and 181–241 °C temperature range for theophylline. Sublimation enthalpy determined by this experimental technique was 110 kJ/mol for caffeine and 130 kJ/mol for theophylline [ 23 ].…”

Section: Resultsmentioning

confidence: 99%

Evaluation of the Sublimation Process of Some Purine Derivatives: Sublimation Rate, Activation Energy, Mass Transfer Coefficients and Phenomenological Models

Cleminte

Ionita²,

Lisa

et al. 2022

Materials

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Caffeine and theophylline are compounds with important applications in the pharmaceutical industry and other fields of the chemical industry. These purine derivatives have simple chemical structures, therefore, the evaluation of their sublimation process contributes to the development of mass transfer analysis methods that can later be applied to other compounds with more complex structures. With the help of thermogravimetric analysis in isothermal conditions, the kinetic study of the sublimation of caffeine and theophylline, along with the evaluation of kinetic parameters (activation energy and the pre-exponential factor), was carried out. Global mass transfer coefficients were determined, which vary for caffeine between 53 × 10−8 and 631 × 10−8 mol/s·m2·Pa, and for theophylline between 68 × 10−8 and 441 × 10−8 mol/s·m2·Pa. The dimensionless equations of the form: Sh=a+b·Rec·Scd have been proposed, which allow the determination of individual mass transfer coefficients at temperatures between 130 and 160 °C for caffeine and between 170 and 200 °C for theophylline.

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Section: Resultsmentioning

confidence: 99%

Evaluation of the Sublimation Process of Some Purine Derivatives: Sublimation Rate, Activation Energy, Mass Transfer Coefficients and Phenomenological Models

Cleminte

Ionita²,

Lisa

et al. 2022

Materials

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“…The mass-transfer coefficient can be calculated using the following equation β normalc = a a 2 + h 2 D normalA , normalB × F ( θ ) × F ( Δ T ) where a is the base radius of the spherical cap-shaped droplet, h is its height in the center, D A,B is the diffusion coefficient, calculated by Fuller et al’s empirical scheme, F (Δ T ) is an empirical function related to the influence of the temperature gradient in the gas phase on the mass-loss process, and F (θ) is an empirical function representing the influence of the contact angle θ. The procedure of the measurements has been fully described elsewhere . The vapor pressures measured in this work are listed in Table .…”

Section: Methodsmentioning

confidence: 99%

“…The procedure of the measurements has been fully described elsewhere. 23 The vapor pressures measured in this work are listed in Table 3. The derivation of the enthalpy and entropy of phase transitions reported in Table 3 is discussed subsequently in the text.…”

Section: Differential Scanning Calorimetrymentioning

confidence: 99%

Thermochemical Properties of Phase Transitions and Solvation for Some Mono- and Di-cyanate Esters at 298.15 K

et al. 2022

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We have obtained the thermochemical properties of the phase transition of six mono- and di-cyanate esters for the first time. Vapor pressure–temperature dependences and enthalpies of vaporization for two mono-cyanate esters were measured by fast scanning calorimetry and transpiration method. Fusion enthalpies of cyanate esters were studied by differential scanning calorimetry. We have developed an additive scheme for the evaluation of solvation enthalpies of cyanate esters based on the reliable data of solution and sublimation enthalpies of one mono-cyanate ester. The proposed scheme and experimental solution enthalpies in different solvents were further used for the determination of the vaporization and sublimation enthalpies of other cyanate esters at 298.15 K.

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“…As can be expected, such data were used for modeling the fate of PAHs in the environment (e.g., Sun et al, Gbeddy et al). They were also used for the development of a vapor pressure group contribution method by Naef and Acree and comparison with vapor pressures obtained via fast DSC and TGA …”

Section: Evaluation Of Literature Cgc Vapor Pressuresmentioning

confidence: 99%

“…As can be expected, such data were used for modeling the fate of PAHs in the environment (e.g., Sun et al, 147 Gbeddy et al 148 ). They were also used for the development of a vapor pressure group contribution method by Naef and Acree 96 and comparison with vapor pressures obtained via fast DSC 149 and TGA. 150 A situation similar to anthracene can be seen in the case of supercooled vapor pressures for adamantane and diamantane.…”

Section: Unreliable Supercooled Vapor Pressures For High-melting Comp...mentioning

confidence: 99%

Estimating Vapor Pressure Data from Gas–Liquid Chromatography Retention Times: Analysis of Multiple Reference Approaches, Review of Prior Applications, and Outlook

et al. 2022

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Reliable methods for determining the vapor pressures of organic materials are of increasing importance as a tool for predicting the behavior and fate of chemicals that are introduced into the environment. In the present work, we analyze the method that relates the gas–liquid chromatography (GLC) retention data, namely, the retention factors (k) of selected organic compounds with their vapor pressures (p 0) using multiple reference standards. Temperature-dependent k values of test chemicals and an adequate number y of reference standard chemicals having directly measured vapor pressure values at temperatures corresponding to GLC measurements are required to apply this method (GLC-RTyS). Retention data of 49 test compounds including a series of alkanes, alkanols, alkyl benzenes, phenols, some (hydro)naphthalene derivatives, and menthol determined on a low-polar dimethylpolysiloxane (HP-1) column at a temperature range from 353 K to (403 or 423) K were used for method validation. We present a first systematic analysis aimed at examining whether and to what extent the selection of experimental conditions might influence/improve the results. Furthermore, we present a review of an alternative multireference correlation gas chromatographic (CGC) method that employs significant extrapolations and is based on the use of adjusted retention time t′ instead of k in order to reveal uncertainties inherent in routine application of this method.

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Application of the Flash DSC 1 and 2+ for vapor pressure determination above solids and liquids

Cited by 18 publications

References 79 publications

Evaluation of the Sublimation Process of Some Purine Derivatives: Sublimation Rate, Activation Energy, Mass Transfer Coefficients and Phenomenological Models

Evaluation of the Sublimation Process of Some Purine Derivatives: Sublimation Rate, Activation Energy, Mass Transfer Coefficients and Phenomenological Models

Thermochemical Properties of Phase Transitions and Solvation for Some Mono- and Di-cyanate Esters at 298.15 K

Estimating Vapor Pressure Data from Gas–Liquid Chromatography Retention Times: Analysis of Multiple Reference Approaches, Review of Prior Applications, and Outlook

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