Critical Surface Tension and Specific Surface Free Energy of Clathrate Hydrate

Abstract

The specific surface free energy (γ sv ) of a solid is the work required to create a unit area of a solid in a vacuum. γ sv is a fundamental physical quantity that plays a central role in cohesion, adhesion, and premelting of a solid and other phenomena like the nucleation work of a solid phase. However, due to experimental difficulties, no specific surface free energy values have been reported for clathrate hydrates. Here we applied the "Zisman plot" to the determination of the critical surface tension, γ c , of ice and tetrahydrofuran (THF) hydrate. The γ c value of ice was found to be very similar to the value reported by Adamson et al. (J. Colloid Interface Sci. 1970, 34, 461−468) for the same homologous series. Then we used the measured γ c value of THF hydrate and the γ sv values of ice reported in the literature to deduce the γ sv value of THF hydrate. The deduced γ sv value of THF hydrate was somewhat lower than that of ice and in the range from 60.4 to 124.2 mJ/m 2 , with an average of 92.3 mJ/m 2 .

Surface Science in the Research and Development of Hydrate-Based Sustainable Technologies

“… − Some properties of the QLL such as diffusion coefficient and interfacial tension can be estimated based on computer simulations. − A question of fundamental importance is how the surface premelting affects the specific surface free energy (γ sv ) of hydrates. Maeda et al was the first research group attempting to estimate γ sv of hydrates using a semiempirical method . They found a γ sv = 60.4–124.2 mJ·m 2 for tetrahydrofuran (THF) hydrate at 277 K. These values of THF hydrate is slightly lower than that of ice, which confirming the similarity between the surfaces of hydrate and ice, i.e.…”

“…Maeda et al was the first research group attempting to estimate γ sv of hydrates using a semiempirical method. 70 They found a γ sv = 60.4−124.2 mJ•m 2 for tetrahydrofuran (THF) hydrate at 277 K. These values of THF hydrate is slightly lower than that of ice, which confirming the similarity between the surfaces of hydrate and ice, i.e. both surfaces are covered by a QLL.…”

Cellulose nanofiber‐based emulsion coatings with enhanced hydrophobicity and surface adhesion for preserving anthocyanins within thermally processed blueberries packed in aqueous media

“…Briefly, fruit was washed by the fresh produce detergent and sequentially treated in 1% (wt/vol) Tween 80, 0.5% (wt/vol) TA, or FA, and 1% (wt/vol) CaCl 2 ·2H 2 O for 10 min, respectively (T80 → TA → CaCl 2 or T80 → FA → CaCl 2 ). CST provides the specific surface free energy of a solid and is determined by measuring the contact angle (θ) of different ST ranges of reference liquids on the surface of solid (Wei & Maeda, 2021). CST of blueberry surface was obtained by extrapolation from Zisman's plot, which was built using water (72.9 dynes/cm at 22°C), formamide (58.4 dynes/cm at 22°C), and 1‐methyl naphthalene (38.9 dynes/cm at 22°C) as reference liquids.…”

“…CaCl 2 ). CST provides the specific surface free energy of a solid and is determined by measuring the contact angle (θ) of different ST ranges of reference liquids on the surface of solid (Wei & Maeda, 2021). CST of blueberry surface was obtained by extrapolation from Zisman's plot, which was built using water (72.9 dynes/cm at 22 C), formamide (58.4 dynes/cm at 22 C), and 1-methyl naphthalene (38.9 dynes/cm at 22 C) as reference liquids.…”

Particles’ Organization in Direct Oil-in-Water and Reverse Water-in-Oil Pickering Emulsions

“…The mass fraction of alcohol was varied between 10 and 20 wt.% which corresponded to liquid/vapor surface tension ranging between 41 and 31 mJ m −2 . The critical surface energy of the particles was determined as the value of the liquid/vapor surface tension corresponding to the mixture containing the minimum amount of propan-2-ol, at which the particles sunk into the liquid [ 25 , 26 ].…”