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Emulsions carbon dioxide

In a 250 ml. conical flask mix a solution of 14 g. of sodium hydroxide in 40 ml. of water and 21 g. (20 ml.) of pure benzaldehyde (Section IV,115). Add 15 g. of hydroxylamine hydrochloride in small portions, and shake the mixture continually (mechanical stirring may be employed with advantage). Some heat is developed and the benzaldehyde eventually disappears. Upon coohiig, a crystalline mass of the sodium derivative separates out. Add sufficient water to form a clear solution, and pass carbon dioxide into the solution until saturated. A colourless emulsion of the a or syn-aldoxime separates. Extract the oxime with ether, dry the extract over anhydrous magnesium or sodium sulphate, and remove the ether on a water bath. Distil the residue under diminished pressure (Fig. 11,20, 1). Collect the pure syn-benzaldoxime (a-benzald-oxime) at 122-124°/12 mm. this gradually solidifies on cooling in ice and melts at 35°. The yield is 12 g. [Pg.719]

Vinylidene Chloride Copolymer Latex. Vinyhdene chloride polymers are often made in emulsion, but usuaUy are isolated, dried, and used as conventional resins. Stable latices have been prepared and can be used direcdy for coatings (171—176). The principal apphcations for these materials are as barrier coatings on paper products and, more recently, on plastic films. The heat-seal characteristics of VDC copolymer coatings are equaUy valuable in many apphcations. They are also used as binders for paints and nonwoven fabrics (177). The use of special VDC copolymer latices for barrier laminating adhesives is growing, and the use of vinyhdene chloride copolymers in flame-resistant carpet backing is weU known (178—181). VDC latices can also be used to coat poly(ethylene terephthalate) (PET) bottles to retain carbon dioxide (182). [Pg.442]

CIS of potassium permanganate in 2000 c.c. of water is placed in a, and an emulsion of 100 grams of the hydrocarbon in 600 c.c. of water is gradually added in small portions. The mixture is kept cool by means of a current of cold water, and shaken continuously. The oxidation products are then treated as follows The liquid is filtered from manganese oxide, and evaporated to about 1000 c.c., saturated with carbon dioxide, and the neutral and unaltered compounds removed ly extract jn with ether in the usual manner. The crude pinonic acid is separated from its potassium salt by sulphuric acid and is then extracted with ether. If /S-pinene be present, nopinic acid will be present... [Pg.43]

Alkalinity and Lime Content. The whole mud alkalinity test procedure is a titration method which measures the volume of standard acid required to react with the alkaline (basic) materials in an oil mud sample. The alkalinity value is used to calculate the pounds per barrel unreacted excess lime in an oil mud. Excess alkaline materials, such as lime, help to stabilize the emulsion and also neutralize carbon dioxide or hydrogen sulfide acidic gases. [Pg.662]

NOTE In simple filming amine formulations ODA is the most widely employed ingredient. Formulations are typically available as 100% concentrated flakes, 2 to 5% strength aqueous solutions, or 5 to 10% strength emulsions. Solid ODA should be stored without exposure to air because it gradually reacts with carbon dioxide to form ODA carbonate, which is white and crumbly in composition. [Pg.539]

One attractive approach to photochemical conversion and storage of solar energy is photofixation of carbon dioxide to C-1 organic compounds (formic acid, formaldehyde, methanol, and methane). Photoreduction of CO2 to formic acid and formaldehyde has been demonstrated by using n-type Bi2S3 and CdS semiconductor powders (particle size 300 00 mesh) as photoelectrocatalysts in emulsions... [Pg.270]

The majority of hydraulic fracturing treatments are performed using water-based fluids foams (with nitrogen or carbon dioxide as the gas phase) have been used extensively in recent years to reduce formation damage. Oil-external emulsions have also been used for... [Pg.16]

Once the emulsifier is well blended into the carbohydrate melt, the flavoring material is added. An emulsion is formed using a flat bladed turbine type agitator (about 4i inches in diameter). The time of agitation is typically about 5 min. The next step involves pressurization of the extrusion vessel with either nitrogen or carbon dioxide. While others have mentioned pressurization of the vessel for extrusion, Miller and Mutka (8) have optimized this parameter for encapsulation efficiency, they found 7-50 psi most suitable for improving encapsulation efficiency. At pressures above 100 psi, they found some emulsions broke and encapsulation efficiency was very poor. [Pg.108]

The environmentally benign, nontoxic, and nonflammable fluids water and carbon dioxide (C02) are the two most abundant and inexpensive solvents on Earth. Water-in-C02 (w/c) or C02-in-water (c/w) dispersions in the form of microemulsions and emulsions offer new possibilities in waste minimization for the replacement of organic solvents in separations, reactions, and materials formation processes. Whereas the solvent strength of C02 is limited, these dispersions have the ability to function as a universal solvent medium by solubilizing high concentrations of polar, ionic, and nonpolar molecules within their dispersed and continuous phases. These emulsions may be phase-separated easily for product recovery (unlike the case for conventional emulsions) simply by depressurization. [Pg.135]

Adamsky, F. A. Beckman, E. J. Inverse Emulsion Polymerization of Acrylamide in Supercritical Carbon Dioxide. Macromolecules 1994, 27, 312. [Pg.173]

Foams, in the form of froths, are intimately involved and critical to the success of many mineral-separation processes (Chapter 10). Foams may also be applied or encountered at all stages in the petroleum recovery and processing industry (oil-well drilling, reservoir injection, oil-well production and process-plant foams). A class of enhanced oil recovery process involves injecting a gas in the form of a foam. Suitable foams can be formulated for injection with air/nitrogen, natural gas, carbon dioxide, or steam [3,5]. In a thermal process, when a steam foam contacts residual crude oil, there is a tendency to condense and create W/O emulsions. Or, in a non-thermal process, the foam may emulsify the oil itself (now as an O/W emulsion) which is then drawn up into the foam structure the oil droplets eventually penetrate the lamella surfaces, destroying the foam [3], See Chapter 11. [Pg.227]

Jacobson GB, Lee CT, Johnston KP et al (1999) Enhanced catalyst reactivity and separations using water/carbon dioxide emulsions. J Am Chem Soc 121 (50) 11902—11903... [Pg.6]

When sodium carbonate, one of the most commonly used alkali in film developers, comes into contact with acid, carbon dioxide gas is released which can cause blistering in the emulsion of both film and paper. The problem is more critical in film where it is appears as a pinhole, usually in dense areas of silver deposits such as the sky. [Pg.103]


See other pages where Emulsions carbon dioxide is mentioned: [Pg.175]    [Pg.227]    [Pg.1141]    [Pg.197]    [Pg.174]    [Pg.363]    [Pg.1514]    [Pg.69]    [Pg.293]    [Pg.350]    [Pg.99]    [Pg.309]    [Pg.320]    [Pg.357]    [Pg.252]    [Pg.547]    [Pg.31]    [Pg.292]    [Pg.227]    [Pg.1141]    [Pg.44]    [Pg.338]    [Pg.780]    [Pg.24]    [Pg.1048]    [Pg.616]    [Pg.205]    [Pg.84]    [Pg.371]    [Pg.316]    [Pg.174]    [Pg.203]    [Pg.1048]   
See also in sourсe #XX -- [ Pg.303 ]




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