ABSTRACT

Tris(2-ethylhexyl) trimellitate (TOTM) was recently suggested as a reference fluid for industrial use associated with high viscosity at elevated temperature and pressure. Viscosity and density data have already been published on one sample covering the temperature range (303 - 373) K and at pressures up to about 65 MPa. The viscosity covered a range from about (9 to 460) mPa s. In the present article we study several other characteristics of TOTM that must be available if it were to be adopted as a standard. First, we present values for the viscosity and density obtained with a different sample of TOTM to examine the important feature of consistency among different samples. Vibrating-wire viscosity measurements were performed at pressures from (5 to 100) MPa, along 6 isotherms between (303 and 373) K. Density measurements were carried out from (293 to 373) K up to 68 MPa, along 4 isotherms, using an Anton Paar DMA HP vibrating U-tube densimeter. Secondly, we report a study of the effect of water contamination on the viscosity of TOTM, performed using an Ubbelhode viscometer under atmospheric pressure. Finally, in order to support the use of TOTM as a reference liquid for the calibration of capillary viscometers, values of its surface tension, obtained by the pendant drop method, are provided.

Compounds

#	Formula	Name
1	C33H54O6	tris(2-ethylhexyl) trimellitate
2	H2O	water

Datasets

The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type	Compound-#	Property	Variable	Constraint	Phase	Method	#Points
POMD	1	Mass density, kg/m3 ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid		Liquid	Vibrating tube method	16
POMD	1 2	Viscosity, Pa*s ; Liquid	Temperature, K; Liquid Mass fraction - 2; Liquid	Pressure, kPa; Liquid	Liquid	Capillary tube (Ostwald; Ubbelohde) method	15
POMD	1 2	Viscosity, Pa*s ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid	Mass fraction - 2; Liquid	Liquid	Vibrating wire viscometry	94
POMD	1 2	Surface tension liquid-gas, N/m ; Liquid	Temperature, K; Liquid	Mass fraction - 1; Liquid	Liquid Gas	Pendant drop shape	7
POMD	1 2	Surface tension liquid-gas, N/m ; Liquid	Temperature, K; Liquid	Mass fraction - 2; Liquid	Liquid Glass	Pendant drop shape	2

Thermodynamics Research Center / ThermoML | Fluid Phase Equilibria

Tris(2-ethylhexyl) trimellitate (TOTM) as a potential industrial reference fluid for viscosity at high temperatures and high pressures: New viscosity, density and surface tension measurements

Diogo, J. C. F.[Joao C. F.], Avelino, H. M. N. T.[Helena M. N. T.], Caetano, F. J. P.[Fernando J. P.], Fareleira, J. M. N. A.[Joao M. N. A.], Wakeham, W. A.[William A.]

ABSTRACT