Copper-acetate

To prepare pure acetic acid (glacial acetic acid), the crude aqueous product is converted into the sodium salt, the latter dehydrated by fusionf and then heated with concentrated sulphuric acid anhydrous acetic acid, b.p. 118°, distils over. Only the preparation of aqueous acetic acid and of crystalline copper acetate is described below. 

To 2 ml. of the ester in a test-tube add slightly more than the same volume of a cold saturated aqueous copper acetate solution. The blue colour of the latter turns immediately to a pale green. Now shake the tube vigorously in order to produce an emulsion of the ester in the aqueous layer. Scratch the sides of the tube with a rod, and shake vigorously as before. Crystallisation may be delayed for about 5 minutes, but, when once started, rapidly gives a copious precipitate... 

Copper salt, (a) Add aqueous copper acetate solution to an aqueous solution of glycine. Note the formation of a blue colour which is considerably deeper than the colour of the original copper acetate solution. On heating the solution, blue needles of the copper salt usually separate. 

Barfoed s reagent Is prepared by dissolving 13-3 g. of crystallised neutral copper acetate in 200 ml. of 1 per cent, acetic acid solution. The reagent does not keep well. 

Paris green, see Copper acetate arsenate(III) (1/3) Pawellite, see Calcium molybdate(VI)(2—)... 

Valentinite, see Antimony(III) oxide Verdigris, see Copper acetate hydrate Vermillion, see Mercury(II) sulflde Villiaumite, see Sodium fluoride Vitamin B3, see Calcium (+)pantothenate Washing soda, see Sodium carbonate 10-water Whitlockite, see Calcium phosphate Willemite, see Zinc silicate(4—)... 

Theophrastos (272—287 Bc) studied the utilisation of acetic acid to make white lead and verdigris [52503-64-7]. Acetic acid was also weU-known to alchemists of the Renaissance. Andreas Libavius (ad 1540—1600) distinguished the properties of vinegar from those of icelike (glacial) acetic acid obtained by dry distillation of copper acetate or similar heavy metal acetates. Numerous attempts to prepare glacial acetic acid by distillation of vinegar proved to be in vain, however. 

High purity acetaldehyde is desirable for oxidation. The aldehyde is diluted with solvent to moderate oxidation and to permit safer operation. In the hquid take-off process, acetaldehyde is maintained at 30—40 wt % and when a vapor product is taken, no more than 6 wt % aldehyde is in the reactor solvent. A considerable recycle stream is returned to the oxidation reactor to increase selectivity. Recycle air, chiefly nitrogen, is added to the air introducted to the reactor at 4000—4500 times the reactor volume per hour. The customary catalyst is a mixture of three parts copper acetate to one part cobalt acetate by weight. Either salt alone is less effective than the mixture. Copper acetate may be as high as 2 wt % in the reaction solvent, but cobalt acetate ought not rise above 0.5 wt %. The reaction is carried out at 45—60°C under 100—300 kPa (15—44 psi). The reaction solvent is far above the boiling point of acetaldehyde, but the reaction is so fast that Httle escapes unoxidized. This temperature helps oxygen absorption, reduces acetaldehyde losses, and inhibits anhydride hydrolysis. 

Copper acetate, ferrous acetate, silver acetate [563-63-3] basic aluminum acetate, nickel acetate [373-02-4] cobalt acetate, and other acetate salts have been reported to furnish anhydride when heated. In principle, these acetates could be obtained from low concentration acetic acid. CompHcations of soHds processing and the scarcity of knowledge about these thermolyses make industrial development of this process expensive. In the eady 1930s, Soviet investigators discovered the reaction of dinitrogen tetroxide [10544-72-6] and sodium acetate [127-09-3] to form anhydride ... 

Catalysts. Iodine and its compounds ate very active catalysts for many reactions (133). The principal use is in the production of synthetic mbber via Ziegler-Natta catalysts systems. Also, iodine and certain iodides, eg, titanium tetraiodide [7720-83-4], are employed for producing stereospecific polymers, such as polybutadiene mbber (134) about 75% of the iodine consumed in catalysts is assumed to be used for polybutadiene and polyisoprene polymeri2a tion (66) (see RUBBER CHEMICALS). Hydrogen iodide is used as a catalyst in the manufacture of acetic acid from methanol (66). A 99% yield as acetic acid has been reported. In the heat stabiH2ation of nylon suitable for tire cordage, iodine is used in a system involving copper acetate or borate, and potassium iodide (66) (see Tire cords). 

Kupfer-asche, /. copper scale, -azetat, n. copper acetate, -azetylen, n. copper acetylide. -bad, n. copper bath, -barre, /. copper bar copper ingot, -belze, /. copper mordant, -blatt, n. copper foil, -blau, n. blue verditer, azurite. -blech, n. sheet copper, copper foil, -blel, n. copper-lead alloy, -bleiglanz, m. Min.) cuproplumbite. -bleivitriol, m. linarite. -blende, /. tennantite. -blute, / copper bloom (capillary cuprite), -braim, n. tils ore (earthy ferruginous cuprite),... 

The mother liquor contains only 2-3 g. more of the diketone, which can be separated as the copper derivative by shaking an ethereal extract with a saturated aqueous solution of copper acetate,... 

Place the prepared copper acetate solution in the beaker and add 10 mL of 20 per cent potassium iodide solution. Set the stirrer in motion and add distilled water, if necessary, until the platinum plate electrode is fully immersed. Use a saturated calomel reference electrode, and carry out the normal potentiometric titration procedure using a standard sodium thiosulphate solution as titrant. 

Does HCN actually exist in Odontosyllis enopla as an activator of luminescence Its existence appears likely based on the following two observations. (1) Using benzidine-copper acetate reagent (Feigl, 1960), a faint positive response of HCN was obtained from... 

A hydroxy and an arylthio group can be added to a double bond by treatment with an aryl disulfide and lead tetraacetate in the presence of trifluoroacetic acid." Manganese and copper acetates have been used instead of Pb(OAc)4. ° Addition of the groups OH and RSO has been achieved by treatment of alkenes with O2 and a thiol (RSH)." Two RS groups were added, to give vie- dithiols, by treatment of the alkene with a disulfide RSSR and Bp3-etherate."° This reaction has been carried... 

In the present study, we report the synthesis, characterisation and catalytic properties (in selective oxidation reactions) of copper acetate, copper tetradecachlorophthalocyanine and copper tetranitrophthalocyanine encapsulated in molecular sieves Na-X, Na-Y, MCM-22 and VPI-5. Both molecular oxygen and aqueous HjOj have been used as the oxidants. The... 

Table 3 Oxidation of phenols (TON ) with Oj over copper acetate-based catalysts at 298 K...

The oxidation of phenol, ortho/meta cresols and tyrosine with Oj over copper acetate-based catalysts at 298 K is shown in Table 3 [7]. In all the cases, the main product was the ortho hydroxylated diphenol product (and the corresponding orthoquinones). Again, the catalytic efficiency (turnover numbers) of the copper atoms are higher in the encapsulated state compared to that in the "neat" copper acetate. From a linear correlation observed [7] between the concentration of the copper acetate dimers in the molecular sieves (from ESR spectroscopic data) and the conversion of various phenols (Fig. 5), we had postulated [8] that dimeric copper atoms are the active sites in the activation of dioxygen in zeolite catalysts containing encapsulated copper acetate complexes. The high substratespecificity (for mono-... 

P-Benzilmonoxime. Boil 10 g. of the pure a-monoxime for 15 minutes with 1 g. of dried animal charcoal in a quantity of pure benzene just sufficient to dissolve the a-monoxime at the boiling point. Filter off the charcoal and allow the filtrate to stand. The p-monoxime -f 0-5 CgH, crystallises slowly on cooling a further crop can be obtained by evapora tion of the mother liquid. An excellent yield of the p-monoxime, m.p. 112°, is obtained. The pure S-oxime causes no colour change with aqueous - alcoholic copper acetate solution if it is contaminated with the a-oxinie, a greenisli colour is produced. 

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