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Oxalic acid, basicity

By reacting aluminum hydroxide with oxalic acid, basic aluminum oxalate can be produced, which is thermally stable to 330°C, losing 51% of its mass on decomposition at temperatures above 450°C. It is reported to have a flame-retarding and smoke-suppressing action similar to ATH, but because of its increased thermal stability, it can be used in polyamides and thermoplastic polyesters. However, unlike magnesium hydroxide, in these polymers it does not cause hydrolytic degradation.2... [Pg.166]

Urea oxalate is also sparingly soluble in amyl alcohol and since urea is soluble in this alcohol, the property may be utilised in separating urea from mixtures. An aqueous extract of the mixture is rendered slightly alkaline with sodium hydroxide solution and extracted with ether this removes all the basic components, but not urea. The residual aqueous solution is extracted with amyl alcohol (to remove the urea) upon adding this extract to a solution of oxalic acid in amyl alcohol crystalline urea oxalate is precipitated. [Pg.442]

Oxalate Acid Number. A metal soap solution is treated with a measured excess of organic acid. Potassium oxalate solution is added to precipitate the metal and the total sample is back-titrated with alkaU to determine its acidity. Acidity is expressed ia acid number units, equivalent to mg KOH per g. A neutral soap gives a 2ero acid number, an acidic soap solution a positive acid number, and a basic soap solution a negative acid number. [Pg.220]

Seventy grams of pinylamine nitrate are treated with a solution of 10 grams of sodium nitrite in 100 c.c. of water for some time. The yellowish oil which separates is distilled with steam, and the distillate is shaken with an oxalic acid solution in order to remove basic compounds, and again distilled with steam. Pinocarveol has the following characters —... [Pg.138]

Another Hydrogenation with Platinum Oxide. JACS, 55, 2694. This method is used to reduce those hydrox-mandelonitriles in the amphetamine section. It uses low pressure and can be used on about any reducible compound. It can also use palladium oxide as the catalyst. A solution of 35.8 g of phenyl-2-propanol in 250 ml of 80% ethanol containing 7.3 g of HCl is hydrogenated for 3 hours in a Parr hydrogenation bottle at 3,5kg/cm or 50 p.s.i, over 0,5 g of platinum oxide (or palladium oxide Raney nickel may also work) or an equimolar ratio of analog catalyst for about 3 hours. Filter off the catalyst and rinse with a little water to wash all the product from the catalyst. Dilute the filtrate to 1 liter of volume with water and extract twice with ether to remove any acid insoluble material. The ether extracts do not contain product. The aqueous layer is made alkaline with solid NaHCOs to a pH of 8-9 and the basic oil which separates is extracted with two 300 ml portions of ether. This ether solution is dried over MgS04, and filtered, then evaporated to remove the ether. To convert to the oxalate, add ether to the crude product and add to a solution of 9.6 g of oxalic acid dihydrate in a small volume of methanol. Give ample... [Pg.34]

Another electron transfer experiment in a system designed by man was carried out by J. W. Dobereiner in 1831. Ddbereiner prepared an aqueous solution containing oxalic acid and iron(III) oxide and exposed it to sunlight in a small glass bulb. He observed evolution of tiny gas bubbles and precipitation of a solid, and was able to identify the gas as C02 and the precipitation as a basic iron(II) oxide, known as Humboldtite [21]. Dobereiner found similar reactions for the salts of Pt, Ag, Ir, and ruled out the correponding dark reactions by careful control experiments. [Pg.7]

Ferric hydroxide is readily soluble in mineral acids yielding the corresponding ferric salt, and in ferric chloride solution yielding oxy compounds which are acidic in their behaviour, decomposing carbonates, and can therefore hardly be termed basic chlorides.3 It dissolves in aqueous oxalic acid to an extent directly proportional to the concentration of the acid, no definite basic oxalate being formed at 25° C. from solution.4 It does not combine with carbon dioxide when freshly precipitated and suspended in water.5... [Pg.125]

Payakoff carried out the synthesis of various oxalate complexes by mechanical activation of the solid oxalic acid with hydroxides and basic salts [35], He demonstrated that the synthesis proceeded with the formation of honey-like mass from which solid complex crystal hydrates are crystallized relatively easily under aging of activating mixtures at room temperature. Ultrafine and highly reactive catalysts, pigments and other compounds of practical importance were obtained by thermal decomposition of the mentioned complexes. [Pg.4]


See other pages where Oxalic acid, basicity is mentioned: [Pg.164]    [Pg.134]    [Pg.869]    [Pg.102]    [Pg.546]    [Pg.167]    [Pg.67]    [Pg.8]    [Pg.9]    [Pg.234]    [Pg.13]    [Pg.331]    [Pg.4]    [Pg.296]    [Pg.449]    [Pg.209]    [Pg.137]    [Pg.449]    [Pg.123]    [Pg.443]    [Pg.136]    [Pg.334]    [Pg.456]    [Pg.638]    [Pg.70]    [Pg.1185]    [Pg.1318]    [Pg.119]    [Pg.871]    [Pg.114]    [Pg.551]    [Pg.174]    [Pg.285]    [Pg.96]    [Pg.45]    [Pg.134]    [Pg.382]    [Pg.97]    [Pg.443]    [Pg.264]   
See also in sourсe #XX -- [ Pg.70 , Pg.97 , Pg.142 ]




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Oxalic acid, acidity

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