Desorption from water

E] Gas absorption aud desorption from water aud organics plus vaporization of pure liquids for Raschig riugs, saddles, spheres, aud rods, dp = nominal pacldug size, Cp = dry pacldug surface area/volume, = wetted pacldug surface area/volume. Equations are dimensionally consistent, so any set of consistent units can be used. <3 = surface tension, dynes/cm. 

Electron-Stimulated Desorption from Water ice Fiims... 

The efficiency of this type of reactor was examined by Maruoka (1982) and Stichlmayr (1979) using the C02 desorption from water in air as a case study. The mass transfer efficiency for each stage was defined as... 

Determine the individual HTUs for the liquid and gas resistances at the bottom and top of the tower. Vendor data for carbon dioxide desorption from water for 2-in FR packing, when corrected to the temperature and system physical properties for this example, give// = 0.83 ft and Hu = 0.80 ft. 

E] Studied oxygen desorption from water into N2. Packing 0.22-mm-diameter stainless-steel mesh. 

Example 8.1.4 Sherwood and Holloway (1940) determined the mass-transfer behavior in O2 desorption from water from a series of Raschig rings of sizes 0.5", 1.0", 1.5" and 2" in a column of diameter 20" at 25 °C. Sherwood et al. (1975), have considered a particular example from this study for 2" Raschig rings, wherein, at superficial liquid and gas velocities of = 0.542 cm/s, (vi ) = 26.3 cm/s and a packed height of 15.5 cm, the values of Hocp and Notp were found to be 29.26 cm and 0.529, respectively. We employ this worked example from Sherwood et al. (1975) to illustrate the application of the axial dispersion analysis just provided. Determine the true values of Hd and Not for this case, given the Henry s law constant for O2 and water at 20 °C and 30 °C to be 4.01 X 10 and 4.75 x lO atm/mole fraction, respectively. You are given that (A.eft.r) = 0.0148 ft Vs. 

Sherwood and Holloway [61] also studied the desorption of oxygen from water. 

Tadaki and Maeda (Tl) examined the desorption of carbon dioxide from water in a bubble-column and analyzed the experimental results under the assumption that while the gas phase moves in piston flow, the liquid undergoes axial mixing that can be characterized by the diffusion model. (Shulman and Molstad, in contrast, assumed piston flow for both phases.) Only poor agreement was obtained between the theoretical model and the experimental... 

The analytical methods for a-sulfo fatty acid esters reported in the literature deal with the determination of the surfactants in different matrices like detergents or product mixtures from the fabrication. The methyl esters of a-sulfo fatty acids can be separated from a mixture of different surfactants together with sulfonated surfactants by adsorption on an anionic exchanger resin such as Dowex 1X2 or 1X8. Desorption from the exchanger resin is successful with sodium hydroxide (2%) in a 1 1 mixture of isopropanol and water [105]. 

We have found that at 60Z R.H. the water concentration In the paint film has increased by l.OZ (m/m) in comparison with that In the wet paint (after correction for the Increase In solid content after spraying). The rate of water absorption by or desorption from the paint layer Is illustrated in Figure 2. 

Figure 2. Rate of water absorption by or desorption from an unplgmented paint layer.

RICEWQ was the first model developed for agrochemical runoff from paddy fields, incorporating aircraft application, dissipation by drift, adhesion on leaf surfaces, and dissipation from the leaf surface in addition to the processes affecting degradation and transport in sediment and paddy water. An important parameter, desorption from sediment to paddy water, is not considered, although this is not as important as other parameters in paddy fields such as sedimentation rate, behavior of SS, etc. 

Figure 261 shows the absorption and the regeneration process schematically. During Absorption the concentrated salt solution is distributed over an exchange surface, which is in contact with an air stream. The air will be dehumidified and the salt solution will be diluted by the absorbed water vapour. During regeneration the diluted solution becomes concentrated again by desorption from a hot air stream. 

Yamashita et al. [33] also studied the effect of BSA on transport properties in Caco-2 assays. These authors observed that the permeability of highly lipophilic molecules could be rate-limited by the process of desorption from the cell surface into the receiving solution, due to high membrane retention and very low water solubility. They recommended using serum proteins in the acceptor compartment when lipophilic molecules were being assayed - a common circumstance in discovery settings. 

Durable changes of the catalytic properties of supported platinum induced by microwave irradiation have been also recorded [29]. A drastic reduction of the time of activation (from 9 h to 10 min) was observed in the activation of NaY zeolite catalyst by microwave dehydration in comparison with conventional thermal activation [30]. The very efficient activation and regeneration of zeolites by microwave heating can be explained by the direct desorption of water molecules from zeolite by the electromagnetic field this process is independent of the temperature of the solid [31]. Interaction between the adsorbed molecules and the microwave field does not result simply in heating of the system. Desorption is much faster than in the conventional thermal process, because transport of water molecules from the inside of the zeolite pores is much faster than the usual diffusion process. 

The stoppers for vials contain a certain amount of water, which depends on the composition of the stoppers. De Grazio and Flynn [1.86] showed, that the selection of the polymer, the additives for the vulcanization, and the filler influence the adsorption and desorption of water. However even the best possible mixture increases the RM in 215 mg sucrose from 1.95 % to 2.65 % during 3 months storage time at room temperature. Other stopper mixtures show an increase up to 1.7 %. Pikal and Shah [1.87] demonstrated, that the desorption of water from the stopper and the absorption of water by the product depends, in the equilibrium state, on the mass and water content of the stopper and the water content and sorption behavior of the dry product. 

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