A reference data set for validating vapor pressure measurement techniques : homologous series of polyethylene glycols

Visa fullständig post



Permalänk

http://hdl.handle.net/10138/231563

Citation

Krieger , U K , Siegrist , F , Marcolli , C , Emanuelsson , E U , Gobel , F M , Bilde , M , Marsh , A , Reid , J P , Huisman , A J , Riipinen , I , Hyttinen , N , Myllys , N , Kurten , T , Bannan , T , Percival , C J & Topping , D 2018 , ' A reference data set for validating vapor pressure measurement techniques : homologous series of polyethylene glycols ' , Atmospheric Measurement Techniques , vol. 11 , no. 1 , pp. 49-63 . https://doi.org/10.5194/amt-11-49-2018

Titel: A reference data set for validating vapor pressure measurement techniques : homologous series of polyethylene glycols
Författare: Krieger, Ulrich K.; Siegrist, Franziska; Marcolli, Claudia; Emanuelsson, Eva U.; Gobel, Freya M.; Bilde, Merete; Marsh, Aleksandra; Reid, Jonathan P.; Huisman, Andrew J.; Riipinen, Ilona; Hyttinen, Noora; Myllys, Nanna; Kurten, Theo; Bannan, Thomas; Percival, Carl J.; Topping, David
Upphovmannens organisation: Department of Chemistry
Department of Physics
Datum: 2018-01-08
Språk: eng
Sidantal: 15
Tillhör serie: Atmospheric Measurement Techniques
ISSN: 1867-1381
DOI: https://doi.org/10.5194/amt-11-49-2018
Permanenta länken (URI): http://hdl.handle.net/10138/231563
Abstrakt: To predict atmospheric partitioning of organic compounds between gas and aerosol particle phase based on explicit models for gas phase chemistry, saturation vapor pressures of the compounds need to be estimated. Estimation methods based on functional group contributions require training sets of compounds with well-established saturation vapor pressures. However, vapor pressures of semivolatile and low-volatility organic molecules at atmospheric temperatures reported in the literature often differ by several orders of magnitude between measurement techniques. These discrepancies exceed the stated uncertainty of each technique which is generally reported to be smaller than a factor of 2. At present, there is no general reference technique for measuring saturation vapor pressures of atmospherically relevant compounds with low vapor pressures at atmospheric temperatures. To address this problem, we measured vapor pressures with different techniques over a wide temperature range for intercomparison and to establish a reliable training set. We determined saturation vapor pressures for the homologous series of polyethylene glycols (H-(O-CH2-CH2)(n)-OH) for n = 3 to n = 8 ranging in vapor pressure at 298 K from 10(-7) to 5 x 10(-2) Pa and compare them with quantum chemistry calculations. Such a homologous series provides a reference set that covers several orders of magnitude in saturation vapor pressure, allowing a critical assessment of the lower limits of detection of vapor pressures for the different techniques as well as permitting the identification of potential sources of systematic error. Also, internal consistency within the series allows outlying data to be rejected more easily. Most of the measured vapor pressures agreed within the stated uncertainty range. Deviations mostly occurred for vapor pressure values approaching the lower detection limit of a technique. The good agreement between the measurement techniques (some of which are sensitive to the mass accommodation coefficient and some not) suggests that the mass accommodation coefficients of the studied compounds are close to unity. The quantum chemistry calculations were about 1 order of magnitude higher than the measurements. We find that extrapolation of vapor pressures from elevated to atmospheric temperatures is permissible over a range of about 100 K for these compounds, suggesting that measurements should be performed best at temperatures yielding the highest-accuracy data, allowing subsequent extrapolation to atmospheric temperatures.
Subject: THERMODYNAMIC PROPERTIES
DICARBOXYLIC-ACIDS
ORGANIC-MOLECULES
AQUEOUS-SOLUTIONS
ETHYLENE-GLYCOL
SOLID-STATE
AEROSOL
EVAPORATION
DROPLETS
DENSITY
114 Physical sciences
116 Chemical sciences
Referentgranskad: Ja
Licens: cc_by
Användningsbegränsning: openAccess
Parallelpublicerad version: publishedVersion


Filer under denna titel

Totalt antal nerladdningar: Laddar...

Filer Storlek Format Granska
amt_11_49_2018.pdf 5.378Mb PDF Granska/Öppna

Detta dokument registreras i samling:

Visa fullständig post