Influence of Isomeric Composition and Sample Handling on the Liquid Density of Hydrofluorethers Measured by Vibrating Tube Densimeter at 0.1 MPa

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11110%2F23%3A10467650" target="_blank" >RIV/00216208:11110/23:10467650 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=lX9v9V4~.R" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=lX9v9V4~.R</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1007/s10765-023-03247-6" target="_blank" >10.1007/s10765-023-03247-6</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Influence of Isomeric Composition and Sample Handling on the Liquid Density of Hydrofluorethers Measured by Vibrating Tube Densimeter at 0.1 MPa

Popis výsledku v původním jazyce

Hydrofluoroethers (HFEs) represent a new family of promising engineering fluids suitable for technical cleaning and cooling of electronic and magnetic devices or as admixtures in refrigerant blends. Here, we report accurate data for the liquid density at 0.1 MPa and temperatures from 273.15K to 343.15K for a series of five HFEs, namely, HFE-7000, HFE-7100, HFE-7200, HFE-7300, and HFE-7500. A highly sensitive vibrating tube densimeter with a borosilicate glass U-tube calibrated according to the procedure by Prokopova et al. (J Chem Thermodyn 173:106855, 2022) provided density data with an expanded uncertainty ( k = 2) of 0.13 kg center dot m(-3). Influences such as sample degassing, water content, or sample temperature before its dosing into the densimeter are discussed. Thanks to the high sensitivity of the used densimeter, an unexpected shift in the density of different HFE-7100 and HFE-7200 liquid samples was detected. Unlike other HFEs, HFE-7100 and HFE-7200 are mixtures of two hardly separable isomers, which were so far considered having identical thermophysical properties. Utilizing nuclear magnetic resonance spectroscopy, the ratio of n-isomer and iso-isomer was inspected for various liquid samples. In the range of iso-isomer mole fraction from 0.61 to 0.77, the new measurements revealed density differences of more than 5 kg center dot m(-3) in case of HFE-7100 and of about 3 kg center dot m(-3) in case of HFE-7200. Consequently, for some applications, the properties of different HFE isomers cannot be considered identical. The Rackett-type correlation for the saturated liquid density was fitted using the new and the literature data.

Název v anglickém jazyce

Influence of Isomeric Composition and Sample Handling on the Liquid Density of Hydrofluorethers Measured by Vibrating Tube Densimeter at 0.1 MPa

Popis výsledku anglicky

Hydrofluoroethers (HFEs) represent a new family of promising engineering fluids suitable for technical cleaning and cooling of electronic and magnetic devices or as admixtures in refrigerant blends. Here, we report accurate data for the liquid density at 0.1 MPa and temperatures from 273.15K to 343.15K for a series of five HFEs, namely, HFE-7000, HFE-7100, HFE-7200, HFE-7300, and HFE-7500. A highly sensitive vibrating tube densimeter with a borosilicate glass U-tube calibrated according to the procedure by Prokopova et al. (J Chem Thermodyn 173:106855, 2022) provided density data with an expanded uncertainty ( k = 2) of 0.13 kg center dot m(-3). Influences such as sample degassing, water content, or sample temperature before its dosing into the densimeter are discussed. Thanks to the high sensitivity of the used densimeter, an unexpected shift in the density of different HFE-7100 and HFE-7200 liquid samples was detected. Unlike other HFEs, HFE-7100 and HFE-7200 are mixtures of two hardly separable isomers, which were so far considered having identical thermophysical properties. Utilizing nuclear magnetic resonance spectroscopy, the ratio of n-isomer and iso-isomer was inspected for various liquid samples. In the range of iso-isomer mole fraction from 0.61 to 0.77, the new measurements revealed density differences of more than 5 kg center dot m(-3) in case of HFE-7100 and of about 3 kg center dot m(-3) in case of HFE-7200. Consequently, for some applications, the properties of different HFE isomers cannot be considered identical. The Rackett-type correlation for the saturated liquid density was fitted using the new and the literature data.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10600 - Biological sciences

Projekt

—

Návaznosti

V - Vyzkumna aktivita podporovana z jinych verejnych zdroju

Rok uplatnění

2023

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

International Journal of Thermophysics

ISSN

0195-928X

e-ISSN

1572-9567

Svazek periodika

44

Číslo periodika v rámci svazku

9

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

21

Strana od-do

139

Kód UT WoS článku

001049276900002

EID výsledku v databázi Scopus

2-s2.0-85168415137