Compressed Liquid Densities of Squalane and Pentaerythritol Tetra(2-ethylhexanoate)

Abstract

New experimental densities are reported for squalane and for branched pentaerythritol tetra(2ethylhexanoate), PEB8, in the compressed liquid state over the temperature range from (278.15 to 353.15) K and for pressures up to 45 MPa. The reliability of the technique and the procedure up to 25 MPa has been verified in our previous works, and in the present work they were checked up to 45 MPa by comparing our experimental densities for heptane with literature data. A total of 297 density values have been measured with a high-pressure vibrating tube densimeter. The correction factor for density due to the sample viscosity has been considered. This factor ranges from 1 × 10 -4 to 1 × 10 -3 g‚cm -3 for PEB8 and from 4 × 10 -5 to 6 × 10 -4 g‚cm -3 for squalane over the entire Tp interval. The pressure and temperature dependencies of squalane and PEB8 densities could be accurately represented by the Tammann-Tait equation with standard deviations of 3 × 10 -5 g‚cm -3 for squalane and 9 × 10 -5 g‚cm -3 for PEB8. These density data were used to analyze the isothermal compressibility, the isobaric thermal expansivity, and the internal pressure of squalane and PEB8.

Densities and Derived Thermodynamic Properties of Imidazolium-, Pyridinium-, Pyrrolidinium-, and Piperidinium-Based Ionic Liquids

“…To check the effect of viscosity in the density, a viscosity correction for compounds with viscosities < 100 mPa · s was applied with the equation proposed for the density uncertainty of an Anton Paar DMA 512 densimeter. 43 For compounds with viscosities higher than 400 mPa · s, the correction factor becomes constant 44 and equal to 0.5 kg · m…”

New Experimental Data and Reference Models for the Viscosity and Density of Squalane

“…; , Fandiño et al 19,20 ; , Tripathi 21 ; , Kumagai et al ; , Fandiño et al 19,20 ; , Tripathi 21 ; , Kumagai et al 22 ; , Tomida et al 23 ; , Ciotta et al 26 ; , Dubey and Sharma 24 ; , Harris 25 ; , Fandiño et al 27 ; , Mylona et al 28 ; , New Data. (4) 37 ; , Pensado et al 38 ; , Bair 39 ; , Paredes et al 40 ; , Comuñas et al 42 ; , Comuñas et al 42 ; , New Data.…”

High‐pressure viscosity and density of carbon dioxide + pentaerythritol ester mixtures: Measurements and modeling

“…In Figures 1 and 2 we have plotted respectively the experimental densities and viscosities, for the mixtures against pressure, along the several isotherms. In Figure 3, the density for these mixtures are compared with the density values of pure PEB8 (previously measured in our laboratory by Fandiño et al 21 ), and of carbon dioxide 17 over the pressure interval of 10-60 MPa and the temperature interval of 303.15-353.15 K. The trends in the density of mixtures with pressure and temperature are similar to those of pure carbon dioxide. The density of the mixtures is, in general, higher than the values for the pure carbon dioxide.…”

“…The density values of the pure components where taken from Pensado et al 17 for carbon dioxide, and from the work of Fandiño et al 21 for the PEB8 lubricant. For the studied mixtures, in the considered (T,p) range this excess property is negative, being at a fixed composition more negative when the pressure decreases and the temperature increases.…”

“…At present, our research group is studying the density [19][20][21] and viscosity [22][23][24] in broad ranges of temperature and pressure of pentaerythritol esters considered as precursors of POE oils (i.e., as components of refrigerant commercial oils), the solubility 25 of carbon dioxide in pentaerythritol esters, and the density and viscosity 17 of mixtures containing POE lubricants and CO 2 .…”