Abstract: The pressure of saturated water vapor over a-CD nH2O hydrates has been measured by static method with membrane-gauge manometer. The temperature dependences of water vapor pressure were obtained in the wide range of temperatures (298–404 K), pressures (0.2–119.7 kPa) and water content (2.61 n 4.61) under condition of a quasi-constant composition of the a-CD nH2O samples. It was observed that water vapor pressure increases proportionally with growth of water content in the a- CD nH2O hydrate samples. The phase transition was revealed at temperature T = 344 K and its thermodynamic characteristics were determined. The values of enthalpy and entropy of water evaporation process from a-CD nH2O (n = 1) were calculated. The analytical expressions for the lnp – 1/T dependences obtained by the approximation of the experimental data enable to calculate the vapor pressure of the a-CD nH2O hydrates within the studied temperature range for any n from 2.61 to 6.10. Experimental data were used to obtain changes in the Gibbs energy when water molecules bind to the a-CD framework. The thermodynamic characteristics obtained in this work are new and valuable data not only for fundamental areal, but also for practical applies.

Cite: Zelenina L.N. , Chusova T.P. , Isakov A.V. , Rodionova T.V. , Villevald G.V. , Manakov A.Y.
Thermodynamic investigation of water evaporation process from a-cyclodextrin hydrates
The Journal of Chemical Thermodynamics. 2021. V.158. 106424 :1-5. DOI: 10.1016/j.jct.2021.106424 WOS OpenAlex

Dates:

Submitted:	Nov 19, 2020
Accepted:	Feb 11, 2021
Published online:	Feb 13, 2021

Identifiers:

Web of science:	WOS:000644964000027
OpenAlex:	W3131010983

Citing:

DB	Citing
OpenAlex	5

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