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Volatility water

Ether solution. Contains water- insoluble amines. Aqueous solution. Will possess ammo, niacal odour of water-soluble amines present. Distil as long as distillate is alkaline to recover volatile water-soluble amines. [Pg.1097]

The distillate may contain volatile neutral compounds as well as volatile acids and phenols. Add a slight excess of 10-20 per cent, sodium hydroxide solution to this distillate and distil until the liquid passes over clear or has the density of pure water. The presence of a volatile, water-soluble neutral compound is detected by a periodic determination of the density (see Section XI,2) if the density is definitely less than unity, the presence of a neutral compound may be assumed. Keep this solution Si) for Step 4. [Pg.1098]

Aqueous solution. Distil. The distillate may contain volatile water-soluble acids. [Pg.1100]

The reaction is completed after 6—8 h at 95°C volatiles, water, and some free phenol are removed by vacuum stripping up to 140—170°C. For resins requiring phenol in only trace amounts, such as epoxy hardeners, steam distillation or steam stripping may be used. Both water and free phenol affect the cure and final resin properties, which are monitored in routine quaHty control testing by gc. OxaHc acid (1—2 parts per 100 parts phenol) does not require neutralization because it decomposes to CO, CO2, and water furthermore, it produces milder reactions and low color. Sulfuric and sulfonic acids are strong catalysts and require neutralization with lime 0.1 parts of sulfuric acid per 100 parts of phenol are used. A continuous process for novolak resin production has been described (31,32). An alternative process for making novolaks without acid catalysis has also been reported (33), which uses a... [Pg.297]

Specific gravity at 2J C Refractive index Efficiency proportions Cold flex lemp.(°C) Volatility Water extraction (%)" hO OCtane extraction (%r ... [Pg.332]

The steroid-loaded formulations are prepared by a patented solvent evaporation process (45,46). Basically, the wall-forming polymer and the steix>id are added to a volatile, water-immiscible solvent. The dispersion or solution is added to an aqueous solution to form an oil-in-water emulsion. The volatile solvent is then removed to afford solid microparticles. The microparticles are usually subd vided with sieves to isolate fractions of the desired diameters. It is i nper-ative that a reliable and reproducible microencapsulation procedure be used to fabricate long-acting formulations. [Pg.16]

Direct emulsification A solution of the polymer within a volatile, water-immiscible organic solvent (or mixture of solvents), or a polymer melt is emulsified within a surfactant-containing aqueous phase. If used, the organic solvent is then removed by steam distillation to obtain the pseudolatices. [Pg.274]

Thermal conduction (also referred to as electrical conductive heating or in situ thermal desorption) supplies heat to the soil through steel wells or with a blanket that covers the ground surface. As the polluted area is heated, the contaminants are destroyed or evaporated. Steel wells are used when the polluted soil is deep. The blanket is used where the polluted soil is shallow. Typically, a carrier gas or vacuum system transports the volatilized water and organics to a treatment system. [Pg.629]

Experiment 2 Saturate distilled water with a rare gas and compare the intensity of the signal with that from air. The luminosity will be enhanced in the rare gas saturated solutions. For any gas atmosphere, add small amounts of volatile water-soluble solutes (e.g. alkyl series alcohols) and quantify the quenching of sonoluminescence as a function of both bulk quencher concentration and surface excess. Good correlation between the extent of quenching and the Gibbs surface excess should be observed. Explain the changes in sonoluminescence intensity when a rare gas atmosphere is used and the quenching of volatile solutes, in terms of simple thermodynamics. [Pg.393]

This method was first reported by Vanderhoff [82] for the preparation of artificial latexes. The polymer and drug are dissolved or dispersed in a volatile water-immiscible organic solvent, such as dichloromethane, chloroform, or ethyl acetate. This is emulsified in an aqueous continuous phase containing a surfactant, such as poly(vinylalcohol), to form nanodroplets. The organic solvent diffuses out of the nanodroplets into the aqueous phase and evaporates at the air/water interface, as illustrated in Figure 6. The solvent is removed under reduced pressure. The nanodroplets solidify and can be separated, washed, and dried to form a free-flowing powder. [Pg.5]

The Maxymillian Technologies, Inc. (formerly Clean Berkshires, Inc.), mobile thermal desorption system (TDS) uses rotary kiln technology to remove contaminants from excavated soils and sediments. Thermal desorption is a physical separation process designed to volatilize water... [Pg.770]

The concentration of butanoic add in milk fat is the principle of the widely used criterion for the detection and quantitation of adulteration of butter with other fats, i.e. Reichert Meissl and Polenski numbers, which are measures of the volatile water-soluble and volatile water-insoluble fatty adds, respectively. [Pg.87]

When we now compare these compounds with the corresponding sodium ones, we find very large differences between them the most striking being that, whereas the sodium compounds are all solid substances of low volatility, those of hydrogen are, without exception, very volatile. Water has the highest boiling point of them all, but... [Pg.92]

Fluid milk is commonly subjected to a combination steam injection/in-fusion and vacuum flash evaporation process to remove volatile off-flavor compounds. The process is designed to remove the same amount of water by the flash treatment as is added during steam injection/infu-sion, so that the composition of the milk remains unchanged. This treatment is most effective for removing volatile, water-soluble flavor compounds, such as those from weeds and feed consumed by the cow. The additional heat from this process usually provides further improvement in product shelf life. [Pg.743]

Activated charcoal High retention of nonpolar volatiles Water absorption. Artifact formation. Some difficulties with desorption Less used for aroma compounds... [Pg.1006]

Ether solution. Aqueous Contains solution. volatile water- Concentrate insoluble by distillation amines contains volatile water- soluble amines ... [Pg.1296]

Ether solution. Aqueous solution. Distil. Contains The distillate may volatile water- contain volatile water-insoluble acids, soluble acids. ... [Pg.1296]

Thermal desorption is a physical separation process. Waste is heated to volatilize water and organic contaminants. A carrier gas or vacuum system transports volatilized water and organics to the gas treatment system. The bed temperatures and residence times designed for these systems will volatilize selected contaminants without oxidation. Three types of thermal desorption are available ... [Pg.81]

Kirchner, J. G. Miller, J. M. Volatile water-soluble and oil constituents of Valencia orange juice. J. Agric. Food Chem., 1957, U, 283-291. [Pg.188]

In addition to the analysis of arson crime scene evidence, thermal desorption has been used for the analysis of residual volatile agents in street drugs and the analysis of stains on forensic evidence. Samples are heated to volatilize water and organic compounds. The organic analytes may then be separated by gas chromatography (Figure 22.2). [Pg.403]

Another important group of anisotropic composite membranes is formed by solution-coating a thin (0.5-2.0 xm) selective layer on a suitable microporous support. Membranes of this type were first prepared by Ward, Browall, and others at General Electric [52] and by Forester and Francis at North Star Research [17,53] using a type of Langmuir trough system. In this system, a dilute polymer solution in a volatile water-insoluble solvent is spread over the surface of a water-filled trough. [Pg.119]


See other pages where Volatility water is mentioned: [Pg.68]    [Pg.291]    [Pg.38]    [Pg.670]    [Pg.64]    [Pg.876]    [Pg.222]    [Pg.11]    [Pg.344]    [Pg.190]    [Pg.153]    [Pg.198]    [Pg.352]    [Pg.708]    [Pg.1100]    [Pg.1100]    [Pg.1745]    [Pg.338]    [Pg.338]    [Pg.254]    [Pg.282]    [Pg.126]    [Pg.231]   


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