Development of the Knudsen effusion methodology for vapour pressure measurements of low volatile liquids and solids based on a quartz crystal microbalance

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22340%2F18%3A43916823" target="_blank" >RIV/60461373:22340/18:43916823 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.1016/j.jct.2018.07.004" target="_blank" >https://doi.org/10.1016/j.jct.2018.07.004</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jct.2018.07.004" target="_blank" >10.1016/j.jct.2018.07.004</a>

Result language

angličtina

Original language name

Development of the Knudsen effusion methodology for vapour pressure measurements of low volatile liquids and solids based on a quartz crystal microbalance

Original language description

The principle of operation, concepts and recent developments of the Knudsen effusion methodology for the vapour pressure measurement of ionic liquids and other low volatile liquids and solids are presented. A new version of a Knudsen effusion apparatus, coupled with a quartz crystal microbalance, which is used for a reliable measurement of the mass flow from a Knudsen effusion cell, is described in detail. In the new system, designed and optimized for the vapour pressure measurement of ionic liquids, it is possible to measure the vapour pressure of small samples using very short effusion time over a wide temperature range. This apparatus allows the vapour pressure measurements using step-temperature and continuous-temperature modes that have the advantage of reducing the measurement time interval and minimize the effect of a sample degradation. A significant number of improvements on the performance and capability for the vapour pressure measurements of ionic liquids has been implemented: in situ temperature control of the vacuum chamber for a better stability of background signal; a new design of a stainless steel effusion cell to decrease the reactivity and sample decomposition; dual temperature control ensuring a positive temperature gradient between bottom and top of the cell in order to avoid the ionic liquids condensation on the effusion cell lid and significantly improved stability of the time frequency derivative at high temperatures; Installation and test of a mass flow tube, on the top of the outlet of the cell lid oven block in order to increase the mass sensitivity coefficient of QCM. The tests and benchmarking concerning the measurement of vapour pressures of ionic liquids performed with [C2mim][NTf2] indicate that the described Knudsen effusion apparatus and methodology is able to produce reproducible and reliable experimental vapour pressure data with an accuracy and quality similar than the achieved in the measurements with low volatile solids. The effect of the improvements on the performance of the Knudsen effusion apparatus was tested and evaluated by the comparison of the vapour pressure results of 1,3,5-triphenylbenzene and 1-ethyl-3-methylimidazolium with the available literature data.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10403 - Physical chemistry

Project

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Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2018

Confidentiality

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

Name of the periodical

Journal of Chemical Thermodynamics

ISSN

0021-9614

e-ISSN

—

Volume of the periodical

126

Issue of the periodical within the volume

November 2018

Country of publishing house

GB - UNITED KINGDOM

Number of pages

16

Pages from-to

171-186

UT code for WoS article

000439575800023

EID of the result in the Scopus database

2-s2.0-85050133648