Evgeniya Kovaleva

Ms. Evgeniya Kovaleva


Research Focus & Metrics

Academic Career Length

3Years (2024-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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13 April 2025 in Molecules
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Journal Article
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Andrei V PolkovnichenkoAndrei V Polkovnichenko
Andrei V Polkovnichenko
EKEvgeniya Kovaleva
Evgeniya Kovaleva
VPViktor I. Privalov
Viktor I. Privalov
NSNikita Alekseevich Selivanov
Nikita Alekseevich Selivanov
SKSergey Kvashnin
Sergey Kvashnin
ELEgor V Lupachev
Egor V Lupachev
The kinetics and chemical equilibrium of the esterification reaction of acetic acid (AAc) and 2,2,3,3,4,4,4-heptafluorobutan-1-ol (HFBol) (using sulfuric acid as a catalyst) are determined experimentally. The study presents the dependences of Keq on the initial molar ratio of reagents, catalyst concentration and temperature. It is shown that all of the above parameters significantly affect the chemical equilibrium of the system. According to the Van’t Hoff equation, the standard enthalpy and standard entropy are calculated from the experimental data. The esterification process of AAc and HFBol is characterized by the negative heat effect (∆rH > 0). The homogeneous and heterogeneous regions of the chemical equilibrium composition at different settings are given. In the homogeneous region of the chemical equilibrium composition, it is found that the rate constant and half-reaction time do not depend on the initial molar ratio of the reagents. The dependencies of the rate constant on the temperature are obtained, and the parameters of the Arrhenius equation are estimated from the experiments.

12 September 2024 in Engineering Proceedings
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Conference Paper
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Andrei V PolkovnichenkoAndrei V Polkovnichenko
Andrei V Polkovnichenko
EKEvgeniya Kovaleva
Evgeniya Kovaleva
NSNikita Alekseevich Selivanov
Nikita Alekseevich Selivanov
TKTatiana Ksenofontova
Tatiana Ksenofontova
SKSergey Kvashnin
Sergey Kvashnin
ELEgor V Lupachev
Egor V Lupachev
As the object of investigation in the present study, reactive distillation based on the transesterification of isopropyl acetate (IPAc) and 2,2,3,3,4,4,4-heptafluorobutanol (HFBol) under acidic conditions is addressed. This process aims to obtain 2,2,3,3,4,4,4-heptafluorobutyl acetate (HFBAc), which is used in the production of non-aqueous electrolytes, ethyllithium sulphate, charge retention medium, ultraviolet light-absorbing oligomers, etc. Through a combination of NMR spectroscopy and GC-MS, it was determined that during the process, the following were primarily formed in the system: target HFBAc and the by-product, isopropanol. The following side-products were identified: di-isopropyl ether, acetic acid, water, and 2,2,3,3,4,4,4-heptafluorobutyl isopropyl ether (HFB-IPEth). No bis(1H,1H-heptafluorobutyl) ether or acetic anhydride were identified in the system. For HFBol, HFBAc and HFB-IPEth the 1H, 19F and 13C{19F}), 19F-19F COSY NMR, and mass spectra were reported in this study.

11 July 2025 in Chemengineering
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Journal Article
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Andrei V PolkovnichenkoAndrei V Polkovnichenko
Andrei V Polkovnichenko
ELEgor V Lupachev
Egor V Lupachev
EKEvgeniya Kovaleva
Evgeniya Kovaleva
SKSergey Kvashnin
Sergey Kvashnin
TCTatiana Chelyuskina
Tatiana Chelyuskina
Andrey A. VoshkinAndrey A. Voshkin
Andrey A. Voshkin
In the present study, a process for the production of 2,2,3,3,4,4,4-heptafluorobutyl acetate (HFBAc) is proposed for the first time. The production process of HFBAc from acetic acid (AAc) and 2,2,3,3,4,4,4-heptafluorobutan-1-ol (HFBol) was carried out at laboratory scale using batch reactive distillation (BRD). The process was conducted at atmospheric pressure in the presence of an acid catalyst, with an excess of AAc relative to HFBol (initial molar ratio of reagents HFBol/AAc is 45/55). During the BRD, the aqueous phase of the distillate was withdrawn from the system, while the organic phase of the distillate was returned as reflux. Since part of AAc is lost along with the aqueous phase of the distillate, a minor excess of AAc is reasonable for maximizing the conversion of the most expensive reagent—HFBol. The losses of AAc and HFBol with the aqueous phase of the distillate were less than 2 mole % and less than 0.5 mole % of the feed, respectively. The purity of HFBAc after BRD was 97.9 wt. %, and the conversion of HFBol exceeded 99 mole % of the feed. The purity of certain product fractions of HFBAc was greater than 99.6 wt. %. The obtained data can be used for industrial technology development to obtain HFBAc.