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Hydroxyacetic acid, oxidative

Reactions and Uses. The common reactions that a-hydroxy acids undergo such as self- or bimolecular esterification to oligomers or cycHc esters, hydrogenation, oxidation, etc, have been discussed in connection with lactic and hydroxyacetic acid. A reaction that is of value for the synthesis of higher aldehydes is decarbonylation under boiling sulfuric acid with loss of water. Since one carbon atom is lost in the process, the series of reactions may be used for stepwise degradation of a carbon chain. [Pg.517]

Organic acid oxidation in conjugation with oxidation of CaS03 slurry was studied for seven acids. Degradation of adipic acid and other aliphatic and sulfo carboxylic acids was least at pH 4.3 with 1.0 mM dissolved Mn and greatest at pH 5.5 without Mn. Hydroxypropionic and hydroxyacetic acids inhibited sulfite oxidation and were less subject to degradation. Fumaric acid degraded faster than the other alternatives. [Pg.243]

Organic acids are normally stable to oxidation, but laboratory and pilot plant results (18) have shown that adipic acid oxidizes in conjugation with sulfite oxidation in the scrubber. This paper reports oxidative degradation rate of adipic acid as a function of pH and Mn concentration (19). Results are also presented on sulfopropionic, sulfosuccinic, succinic, hydroxypropionic, and hydroxyacetic acids (20). [Pg.245]

Hydroxyacetic and hydroxypropionic acids inhibited sulfite oxidation at concentrations as low as 10 mM. At pH 5.0, 0.3 mM Mn was sufficient to overcome the inhibiting effects of 10 mM hydroxyacetic acid (HA4, HA5). In general, the hydroxy acids had little effect on the oxidation rate in the presence of 1 mM Mn. [Pg.260]

HYDROXIDE de POTASSIUM (French) (1310-58-3) see potassium hydroxide. HYDROXY No. 253 (25154-52-3 84852-15-3) see nonylphenol. HYDROXYACETIC ACID (79-14-1) C2H4O3 Combustible solid.Dust may form explosive mixture with air (Fire Rating 1). Aqueous solution is a medium-strong organic acid. Incompatible with sulfuric acid, caustics, ammonia, aliphatic amines, isocyanates, alkylene oxides, epichloro-hydrin, strong oxidizers. In heat of decomposition (above 212°F/100°C) or fire, carbon dioxide and carbon monoxide may be formed. [Pg.565]

HYDROXYACETIC ACID (79-14-1) Combustible solid. Dust forms an explosive mixture with air. Aqueous solution is a medium-strong organic acid. Incompatible with sulfuric acid, caustics, ammonia, aliphatic amines, isocyanates, alkylene oxides, epichlorohydrin, strong oxidizers. [Pg.638]

The rate of ceric oxidation of substituted benzilic (2,2-diphenyi-2-hydroxyacetic) acid in sulfuric add, aqueous perchloric/acetic add and acetonitrile is the subject of two reports from Hanna and Sarac (1977a, b). The reaction proceeds like the other a-hydroxycarboxylic acids by oxidative decarboxylation, producing substituted benzo-phenones and COj. The primary interest in the first of these two reports (Hanna and Sarac 1977a) is in the organic chemical aspects of the reactions. However, it is observed that the relative rates vary with the media in the order H2SO4 > HC104/acetic acid > acetonitrile. Although little mechanistic information exists, it is apparent that the oxidation proceeds via an inner-sphere, electron transfer process. [Pg.370]

Formic and acetic acids are most attractive, but would probably be volatile under scrubber conditions (8). Succinic and lactic acids would not be cost-effective if purchased at market price. Fumaric acid is more subject to oxidative degradation. Phthalic and Benzoic acids may give undesirable aromatic degradation products. Therefore, the most useful buffers appear to be hydroxypropionic, sulfosuccinic, fumaric, sulfopropionic, adipic, and hydroxyacetic. [Pg.253]

The combination of A -bromoacetamidc, silver acetate, and dry acetic acid has been shown to be superior to Woodward s procedure for the rfy-hydroxylation of olefins. Work up of the reaction mixture is simply effected by hydrolysis of the dioxolenium ion, followed by cleavage of the hydroxyacetate intermediate with lithium aluminium hydride. The use of a co-oxidant, such as sodium chlorate or hydrogen peroxide, allows the addition of catalytic quantities of osmium tetroxide to prepare c/y-diols from olefins. However the reaction is often complicated by further oxidation of the glycol to the a-ketol. The use of tertiary amine A -oxides, particularly A -methylmorpholine A -oxide, prevents this oxidation and gives higher yields of the desired product (Table 6). Another variation on this theme employs... [Pg.21]

On the other hand, the oxidation of propanal to lactic acid involves five steps (1) acetaliza-tion of propanal (2) conversion of acetal to a vinyl ether (3) oxidation of the vinyl ether to a-hydroxyacetal (4) hydrolysis of the acetal to a-hydroxy propanal and (5) oxidation of the latter to lactic acid over Pt/C. All of the steps are feasible with heterogeneous catalysts, and an overall yield of over 80% to lactic acid was reported however, these methods are laborious (Dakka and Goris, 2006). [Pg.261]


See other pages where Hydroxyacetic acid, oxidative is mentioned: [Pg.516]    [Pg.625]    [Pg.640]    [Pg.1146]    [Pg.285]    [Pg.324]    [Pg.253]    [Pg.233]    [Pg.6]    [Pg.75]    [Pg.121]    [Pg.146]    [Pg.11]    [Pg.27]    [Pg.65]    [Pg.173]    [Pg.173]    [Pg.173]    [Pg.173]    [Pg.173]    [Pg.328]    [Pg.1012]    [Pg.13]   


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3-Hydroxyacetals

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