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Acid continued sulfo

In a continuous model river test system it can be shown that after passage through a sewage treatment plant ester sulfonates have no significant influence on the qualitative and quantitative composition of the biocenosis of a receiving water [113]. All the investigations into the environmental fate of a-sulfo fatty acid esters demonstrate that aquatic toxicity is alleviated by their fast ultimate biodegradability, which allows them to be classified as environmentally compatible. [Pg.495]

The next step in the manufacture is ripening, whose object is to convert the triester, the primary cellulose acetate, to a secondary acetate having an average of about 2.35-2.40 acetyl and no sulfo groups (if any sulfuric acid is used in pretreatment) per anhydroglucose unit. While the cellulose sulfo-acetate is still in the acetylizer, sufficient water is added to react with the excess anhydride and start the hydrolysis of the ester. Usually the water is used as a solution of sodium or magnesium acetate, which increases the pH and promotes hydrolysis. The temperature is raised to about 70-80°C, by direct injection of steam to speed up the reaction. Hydrolysis is continued until the desired acetyl content is obtained. When this value is reached, an aqueous solution of magnesium or sodium acetate is added to cool the batch and stop the hydrolysis. It is then ready for precipitation. For example,... [Pg.450]

Effect of Sulfuric Acid on Organic Compounds. The continuing controversy regarding the constitution and formation of the so-called sulfo acids, etc., makes it appropriate to discuss in somewhat more detail those reactions of sulfuric acid on organic compounds in which so-called copulated compounds are formed. [Pg.121]

Emulsion polymerization typically refers to the polymerization of a nonaqueous material in water. The polymerization of a water-soluble material in a nonaqueous continuum has been called inverse emulsion polymerization. The inverse emulsion polymerization technique is used to synthesize a wide range of polymers for a variety of applications such as wall paper adhesive, waste water fiocculant, additives for oil recovery fluids, and retention aids. The emulsion polymerization technique involves water-soluble polymer, usually in aqueous solution, emulsified in continuous oil phase using water in oil emulsifier. The inverse emulsion is polymerized using an oil- or water-soluble initiator. The product is a colloidal dispersion of sub-microscopic particles with particle size ranging from 0.05 to 0.3 pm. The typical water-soluble monomers used are sodium p-vinyl benzene sulfonate, sodium vinyl sulfonate, 2-sulfo ethyl acrylate, acrylic acid, and acrylamide. The preferred emulsifiers are Sorbitan monostearate and the oil phase is xylene. The proposed kinetics involve initiation in polymer swollen micelles, which results in the production of high molecular weight colloidal dispersion of water-swollen polymer particles in oil. [Pg.1065]

Nafion resins have high chemical and thermal stability. The maucimum continuous operation temperature of Nafion-H is about 430 K in anhydrous systems. The maximum temperature in aqueous systems is 420 — 510 K. Besides its thermal and chemical stability, the feature that makes Nafion type polymers catalytically useful is their high acid strength of the acid form of polymers (Nafion-H ). Since the sulfo group is attached to a highly electron-withdrawn perfluoroalkyl backbone, a relatively high polarization of O-H bond results. Thus, Hammett Ho acidity function value of Nafion-H was estimated to be -10 —12, which is comparable to or stronger than that of 96-100% sulfuric acid. ... [Pg.174]


See other pages where Acid continued sulfo is mentioned: [Pg.394]    [Pg.396]    [Pg.466]    [Pg.494]    [Pg.516]    [Pg.288]    [Pg.411]    [Pg.412]    [Pg.27]    [Pg.107]    [Pg.257]   
See also in sourсe #XX -- [ Pg.251 , Pg.554 ]




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4 -sulfo

Acidity continued

Acids continued

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