Application d'un reactif sulfovanadique en milieu acetique anhydre a l'etude analytique de quelques acides α-carbonyles ou α-hydroxyles
✍ Scribed by D. Pradeau; M. Hamon; M. Arnould
- Publisher
- Elsevier Science
- Year
- 1986
- Tongue
- English
- Weight
- 539 KB
- Volume
- 183
- Category
- Article
- ISSN
- 0003-2670
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✦ Synopsis
RfiSUMfi L'obtention d'un reactif sulfovanadique en milieu acetique anhydre a permis d'etudier les cin&iques d'oxydation d'acides cY-carbony& (glyoxylique, pyruvique, ph&ylglyoxylique) et d'acides cu-alcools (glycolique, lactique, mandklique, gluconique). L'etude de reproductibilite montre la possibilite d'une reaction immediate pouvant 8tre utilisee pour un dosage. Ser.11 l'acide lactique, qui s'oxyde selon une cinetique lente, ne se p&e pas P un dosage instantan& SUMMARY
(Application of a vanadium(V) reagent in anhydrous acetic acid to the determination of some a-carbonyl or or-hydroxyl carboxylic acids). The reagent is prepared from vanadium
pentoxide and sulfuric acid in anhydrous acetic acid medium. The oxidation kinetics of various cu-carbonyl (glyoxylic, pyruvic, phenylglyoxylic) and or-hydroxyl (glycolic, lactic, mandelic, gluconic) acids are described. A study of the reaction stoichiometry shows that the immediate reaction, corresponding to the consumption of 2-9 mol V(V) mol-' of acid, depending on the acid, is useful quantitatively, except for lactic acid which gives a slow non-stoichiometric reaction.