Density, Viscosity, Speed of Sound, and Bulk Modulus of Methyl Alkanes, Dimethyl Alkanes, and Hydrotreated Renewable Fuels

Abstract

The density, viscosity, and speed of sound were measured in this work for pure component branched alkanes (2-methyloctane, 4-methyloctane, 2methylnonane, 2-methyldecane, 3-methylundecane, 2-methylpentadecane, 7methylhexadecane, 3,6-dimethyloctane, and 3,5-dimethylheptane) commonly found in hydrotreated renewable fuels (HRFs) and for HRFs from tallow, camelina oil, and algae and waste cooking oil blended 50/50 with petroleum diesel. The density and viscosity were measured at temperatures from (283.15 to 373.15) K and ranged from (661 to 788) kg•m −3 for density and (0.261 to 5.36) mPa•s for viscosity. Speed of sound data were measured at temperatures from (283.15 to 323.15) K and spanned from (1081 to 1393) m•s −1 . The bulk modulus was calculated from the density and speed of sound data, and its values varied from (809 to 1527) MPa. All values increased as the carbon chain length on the alkane increased. All physical property values for the HRFs fell between those measured for individual pure component branched alkanes, providing property data for the development of surrogate mixtures for these renewable fuels.

Viscosity and Surface Tension of Branched Alkanes 2-Methylnonane and 4-Methylnonane

“…Liquid dynamic viscosities η′ of 2-methylnonane and 4-methylnonane (upper panel) and their relative deviations from calculated values η′ calc based on eq (lower panel) close to saturation conditions from surface light scattering as a function of temperature T in comparison with literature data: ○, 2-methylnonane, this work; ◒, 2-methylnonane, SVM 3000, Luning Prak et al; ◑, 2-methylnonane, Ubbelohde viscometer, Geist and Cannon; ◊, 4-methylnonane, this work; □, 4-methylnonane, Ubbelohde viscometer, Geist and Cannon;  , eq using coefficients from Table .…”

“…Liquid densities ρ′ of 2-methylnonane and 4-methylnonane (upper panel) and their relative deviations from calculated values ρ′ calc based on eq (lower panel) at ambient pressure as a function of temperature T in comparison with literature data: ○, 2-methylnonane, DMA 5000 M, this work; ●, 2-methylnonane, DMA 4200 M, this work; ◒, 2-methylnonane, SVM 3000, Luning Prak et al; ◐, 2-methylnonane, DSA 5000, Luning Prak et al; ◓, 2-methylnonane, Calingaert and Soroos; ◑, 2-methylnonane, Geist and Cannon; ⊗, 2-methylnonane, pycnometer, Mears et al; ◇, 4-methylnonane, DMA 5000 M, this work; ⧫, 4-methylnonane, DMA 4200 M, this work; diamond top solid, 4-methylnonane, Calingaert and Soroos; diamond right solid, 4-methylnonane, Geist and Cannon; diamond bottom solid, 4-methylnonane, pycnometer, Trew;  , eq using coefficients from Table .…”

“…All experimental density data used for the following data comparison have been measured at atmospheric pressure, that is, at a pressure of about 0.1 MPa. The data for 2-methylnonane reported by Luning Prak et al were obtained using two devices from Anton Paar in the form of a SVM 3000 Stabinger viscometer between 283.15 and 373.15 K as well as a DSA 5000 density and sound analyzer between 283.15 and 323.15 K. Taking into account the uncertainty of 0.3 kg·m –3 for the SVM 3000 device and 0.2 kg·m –3 for the DSA 5000 device, that is, relative uncertainties between 0.027 and 0.045%, good agreement between their concordant data sets and our correlation within combined uncertainties is found. Regarding all other available literature data for ρ′ discussed below, no experimental uncertainties are specified.…”

“…For the two branched methylnonanes studied in the present work, three experimental data sets for the liquid viscosity are available, which were obtained at a pressure of about 0.1 MPa and are limited to a maximum temperature of 373.15 K. For the data for 2-methylnonane measured by Luning Prak et al 21 with a SVM 3000 Stabinger viscometer between 283.15 and 373.15 K and an uncertainty of about 1%, the relative deviations from our fitted experimental data are between −4.4 and +2.3%. Except for two data points, all these deviations are within combined experimental uncertainties.…”

Density, Viscosity, Speed of Sound, Bulk Modulus, Surface Tension, and Flash Point of Selected Ternary Mixtures of n-Butylcyclohexane + a Linear Alkane (n-Hexadcane or n-Dodecane) + an Aromatic Compound (Toluene, n-Butylbenzene, or n-Hexylbenzene)

“…All methods have been described previously. , Density and speed of sound were measured using an Anton Paar DSA 5000 Density and Sound Analyzer at temperatures between (293.15 and 333.15) K. The DSA 5000 measures speed of sound using a propagation time technique with one transducer emitting sound waves at a frequency of approximately 3 MHz and a second transducer receiving those waves . The viscosity and density were measured using Anton Paar SVM 3000 Stabinger Viscometer at temperatures between (293.15 and 343.15) K. The accuracy of the SVM 3000 Stabinger Viscometer was tested using a certified viscosity reference standard (Standard S3, Cannon Instrument Company).…”