Experimental vapour pressures of eight n-alkanes (C17, C18, C20, C22, C24, C26, C28 and C31) measured at ambient temperatures. (15th September 2019)

• Record Type: Journal Article
• Authors: Alam, Mohammed S.; Nikolova, Irina; Singh, Ajit; MacKenzie, A.R.; Harrison, Roy M.
• Is Part Of: Atmospheric environment. Volume 213(2019)
• Page Start: 739
• Page End: 745
• Publication Date: 2019-09-15
• Subjects: Physico-chemical properties -- Vapour pressure -- n-Alkanes; Air -- Pollution -- Periodicals; Air -- Pollution -- Meteorological aspects -- Periodicals; 551.51
• DOI: 10.1016/j.atmosenv.2019.06.025
• Languages: English
• ISSNs: 1352-2310

Abstract

Abstract: We present direct room-temperature vapour pressure measurements for eight semi-volatile n-alkanes of atmospheric importance. Measured vapour pressures range from 8.4 ± 1.6 × 10 −3 Pa for C17, to 1.7 ± 0.6 × 10 −8 Pa for C31 . The new measurements for C17 –C18 are in reasonable agreement but at the lower end of values in the literature; the new measurements for C28 and C31 are one-to-two orders of magnitude higher than most literature values, but six orders of magnitude higher than the lowest values in the literature. Our measurements are suitable for atmospheric aerosol modelling and interpretation of environmental measurements, interpolated in carbon number where necessary, and extrapolated over temperatures relevant to the atmospheric boundary layer using the Clausius-Clapeyron equation with literature values of the enthalpy of vaporisation. Highlights: High MW alkanes are semi-volatile and vapour pressure is an important property. Reported individual vapour pressures range over up to 8 orders of magnitude. New measurements are made at tropospheric ambient temperatures.