Surface Tension Measurements by Pendant Drop Method of 10 Pure Long-Chain Alkanes and Alcohols for Temperatures up to 573.15 K

Abstract

As the main components of synthetic hydrocarbons obtained using gas to liquid conversion technologies, long-chain alkanes and alcohols play an important role in the Fischer−Tropsch process. So the reliable surface tension data of these fluids are significant for the understanding and eventual improvement of synthesis efficiency. In the present study, a new high temperature and high pressure pendant drop apparatus was developed and tested with n-heptane at temperatures from (303.15 to 473.15) K, and a good agreement between the experimental data and the literature data could be found. With the new apparatus, the experimental surface tension measurements of ndodecane, n-hexadecane, 2,2,4,4,6,8,8-heptamethylnonane, n-octacosane, squalane, 1-dodecanol, 1,12-dodecandiol, 2-butyl-1-octanol, 1-hexadecanol and 2hexyl-1-decanol were performed under saturation conditions over the temperature range from 303.15 K (348.15 K for n-octacosane and 1-hexadecanol, 373.15 K for 1,12-dodecandiol) to 573.15 K. The combined expanded uncertainties of temperature and surface tension with a level of confidence of 0.95 (k = 2) are estimated to be 20 mK and less than 1.5% over the entire temperature, respectively. Furthermore, the surface tension data were correlated with the modified van der Waals equation, and the average absolute deviations are within 0.65%. On the basis of the correlations, the comparisons of our experimental data with the available literature data were discussed, and the satisfactory agreement revealed that the experimental results of this work were reliable and reasonable.

Solvents and Stabilization in Ionic Liquid Films

“…Surface tension was measured using the pendant drop method. The values we observe are either very close to known literature values or expected from known trends in the physical properties of mixtures. − …”

Decrease in the Surface Tension of Nanobubble Dispersion in Water: Results of Surface Excess of Bulk Nanobubbles at Interfaces

“…The measurement results in the figure correspond to those after 0 s of retention time described in the following part of this paragraph. A decreasing tendency with an increase in retention time, which is an elapsed time from the moment of droplet formation, however, was observed in some reports. − The time evolution of surface tension for NB dispersion has been examined. Figure exhibits the time evolution of surface tension from 0 to 1440 s of retention time for pure water and NB dispersions of two different number concentrations, 1.78 × 10 9 and 4.36 × 10 9 mL –1 .…”

“…In principle, the influence of evaporation from the surface of water drop is inevitable in the PD method. In the case of measuring a high volatility liquid, the needle and water drop is sealed in a gas-tight cuvette to suppress the evaporation. , Such a measurement setup enables an equilibrium of vapor atmosphere and results in an equilibrium of surface tension eventually . The surface tension measured in an open system adopted in this study, however, does not reach such an equilibrium.…”

Energetic and Structural Characterizations of the PET–Water Interface as a Key Step in Understanding Its Depolymerization

“…We obtained work of adhesion values of 85.3 and 86.1 mJ m –2 for the amorphous and crystalline systems, respectively. The experimental liquid–vapor surface tension of dodecane is about γ LV = 23.8 mJ m –2 . Using this result and eq , we obtained a value for cos θ greater than 1, meaning that the solid–liquid work of adhesion PET–dodecane is maximum.…”

“…We obtained work of adhesion values of 85. m −2 . 81 Using this result and eq 4, we obtained a value for cos θ greater than 1, meaning that the solid−liquid work of adhesion PET−dodecane is maximum. These results agree with the experimental observations.…”