Studies of the rate of water evaporation through adsorption layers using drop shape analysis tensiometry

Drying rate variations of latex dispersions due to salt induced skin formation

“…Due to the adsorption of SDS molecules on the latex particles the apparent CMC value was higher than CMC for SDS in pure water (8.4 mmol/L at 20 • C) [31]. There are reports in the literature on reduction of the evaporation rate of water by adsorbed dense alkane and/or protein surface layers but no significant influences from the presence of SDS surface layers have been observed [32]. It is also unlikely that variations between the samples in the amount of accumulated latex particles at the top surface caused the observed differences in the initial evaporation rate.…”

Diffusion-controlled evaporation of sodium dodecyl sulfate solution drops placed on a hydrophobic substrate

“…The critical micelle concentration (cmc) of SDS in pure water at 25°C was determined as 8.0-8.2 mM [9]. However, there are only a few reports on the use the drops of the aqueous SDS surfactant solutions during the evaporation studies [10][11][12][13]. Birdi and Vu studied the evaporation of sessile drops of aqueous solutions of ionic detergents, sodium dodecyl sulfate (SDS), and cetyltrimethylammonium bromide (CTAB), placed on a glass surface in order to determine the role of electrostatic interactions present at the liquid-glass interface.…”

“…In contrast to the experimental findings given above, Lunkenheimer and Zembala studied the water evaporation retardation by using soluble surfactants such as sodium salts of myristic, palmitic, perfluorodecanoic acid and also SDS in comparison with insoluble n-decanol monolayer in a vapor pressure osmometer and determined that the soluble surfactants have only limited effect on evaporation retardation which was much less than insoluble monolayers since they cannot form densely packed compact adsorption layers [12]. Fainerman et al studied the rate of water evaporation from drops covered by adsorbed layers of some proteins and surfactants using drop shape analysis tensiometry [13]. They concluded that the adsorbed layers of ordinary surfactants, SDS and C 14 (EO) 8 did not affect the water evaporation rate remarkably when compared with the insoluble n-dodecanol monolayer which decreased the water evaporation rate by 20-25% [13].…”

Vacuum evaporation of surfactant solutions and oil-in-water emulsions

“…The water film between droplets is closely related to these interactions, especially at high oil concentrations, i.e. at the end of the evaporation process [25,32]. Water films are thicker when ionic surfactants are employed [23,24], because of the high electrostatic repulsions between oil droplets.…”

“…High heat transfer rates increase the evaporation rate, with a subsequent decrease of the condensate quality [13,19,30,31]. The effect of operating pressure has also been investigated, at constant heat transfer rates [16,32]. No clear conclusion has been reached, but likely a decrease in the working pressure increases the condensate quality.…”