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Red cake

The principal vanadium-bearing ores are generally cmshed, ground, screened, and mixed with a sodium salt, eg, NaCl or Na2C02- This mixture is roasted at ca 850°C and the oxides are converted to water-soluble sodium metavanadate, NaVO. The vanadium is extracted by leaching with water and precipitates at pH 2—3 as sodium hexavanadate, Na V O, a red cake, by the addition of sulfuric acid. This is then fused at 700°C to yield a dense black product which is sold as technical-grade vanadium pentoxide. This product contains a minimum of 86 wt % V20 and a maximum of 6—10 wt % Na20. [Pg.382]

The red cake can be further purified by dissolving it in an aqueous solution of Na2C02- The iron, aluminum, and silicon impurities precipitate from the solution upon pH adjustment. Ammonium metavanadate then precipitates upon the addition of NH Cl and is calcined to give vanadium pentoxide of greater than 99.8% purity. [Pg.382]

The usual extraction procedure is to roast the crushed ore, or vanadium residue, with NaCl or Na2C03 at 850°C. This produces sodium vanadate, NaV03, which is leached out with water. Acidification with sulfuric acid to pH 2-3 precipitates red cake , a polyvanadate which, on fusing at 700°C, gives a black, technical grade vanadium pentoxide. Reduction is then necessary to obtain the metal, but, since about 80% of vanadium produced is used as an additive to steel, it is usual to effect the reduction in an electric furnace in the presence of iron or iron ore to produce ferrovanadium, which can then be used without further refinement. Carbon was formerly used as the reductant, but it is difficult to avoid the formation of an intractable carbide, and so it has been superseded by aluminium or, more commonly, ferrosilicon (p. 330) in which case lime is also added to remove the silica as a slag of calcium silicate. If pure vanadium metal is required it can... [Pg.977]

Vanadium usually is recovered from its ores by one of two processes, (1) leaching raw mineral with hot dilute sulfuric acid, and (2) roasting ore with common salt to convert vanadium into water soluble sodium vanadates. In the sulfuric acid leaching process, vanadium is extracted from acid leach liquors by solvent extraction with an aliphatic amine or an alkyl phosphoric acid in kerosene. The organic solvent extract then is treated with an aqueous solution of ammonia in the presence of ammonium chloride to convert vanadium into ammonium metavanadate. Alternatively, the organic extract is treated with dilute sulfuric acid or an aqueous solution of soda ash under controlled conditions of pH. Vanadium is precipitated from this solution as a red cake of sodium polyvanadate. [Pg.963]

Alternatively, ore is roasted with common salt and the residue leached with water or sodium carbonate solution. To this aqueous solution of sodium vanadates, sulfuric acid is added and pH is adjusted between 2 and 3. Vanadate precipitates as a red cake of sodium polyvanadate. [Pg.963]

The sodium polyvanadate obtained above by either method is decomposed thermally at 700°C producing a melt of vanadium pentoxide, V2O5. Pentoxide obtained at this stage is in impure form. Purified vanadium pentoxide is obtained by dissolving the red cake in sodium carbonate solution to precipitate ammonium metavanadate. The metavanadate is decomposed at 320 to 430°C to form highly purified vanadium pentoxide. [Pg.963]

Vanadium pentoxide is an intermediate in recovering vanadium from minerals (See Vanadium). Sodium polyvanadate, obtained as a red cake in one of the steps in extracting vanadium from its ores is calcined at 700°C in air to form a melt of vanadium pentoxide. Pentoxide is prepared in purified form by dissolving red cake in sodium carbonate solution followed by addition of an aqueous solution of ammonia and ammonium chloride. Ammonium metavanadate is precipitated which on decomposition at 320 to 430°C forms vanadium pentoxide. [Pg.965]

This is the recipe for my wedding cake, a bright red cake that says love" in the prettiest way. I believe that whatever lovejou put into the cake can be tasted. Our friends baked it for us, and instead of an elaborate decoration or cake topper, they used organic wildfowers to cover the cake, which went along with the casual tone of our wedding. [Pg.60]

The procedure is the same as in method II for NagSg. A hard, wine-red cake of KgS is formed on cooling the melt. [Pg.366]

The reaction mass, which converts to a solid red cake, is cooled and pulverized, washed briefly with a large amount of cold water and then with acetone (to remove excess FeCl3), and dried in vacuum. [Pg.1501]

The flask is detached and the red cake of phosphorus and diphosphorus tetraiodide is broken up by means of a glass rod into a coarse powder, preferably in an atmosphere of carbon dioxide. Although this mixture is quite inflammable, especially if some carbon disulfide remains, it may be ground quickly in a clean, dry mortar that is blanketed by a stream of carbon dioxide. [Pg.143]

Vanadium may be recovered, together with uranium, as an artificial carnotite or yellow cake , Na2O.2UO8.V2O5.nH2O, by the addition of sulphuric acid. Additional acid then precipitates the excess vanadium as V2OS or red cake . [Pg.42]

Phthalide. In a 1 litre bolt-head flask stir 90 g. of a high quality zinc powder to a thick paste with a solution of 0 5 g. of crystallised copper sulphate in 20 ml. of water (this serves to activate the zinc), and then add 165 ml. of 20 per cent, sodium hydroxide solution. Cool the flask in an ice bath to 5°, stir the contents mechanically, and add 73-5 g. of phthalimide in small portions at such a rate that the temperature does not rise above 8° (about 30 minutes are required for the addition). Continue the stirring for half an hour, dilute with 200 ml. of water, warm on a water bath imtil the evolution of ammonia ceases (about 3 hours), and concentrate to a volume of about 200 ml. by distillation vmder reduced pressure (tig. 11,37, 1). Filter, and render the flltrate acid to Congo red paper with concentrated hydrochloric acid (about 75 ml. are required). Much of the phthalide separates as an oil, but, in order to complete the lactonisation of the hydroxymethylbenzoic acid, boil for an hour transfer while hot to a beaker. The oil solidifles on cooling to a hard red-brown cake. Leave overnight in an ice chest or refrigerator, and than filter at the pump. The crude phthalide contains much sodium chloride. RecrystaUise it in 10 g. portions from 750 ml. of water use the mother liquor from the first crop for the recrystaUisation of the subsequent portion. Filter each portion while hot, cool in ice below 5°, filter and wash with small quantities of ice-cold water. Dry in the air upon filter paper. The yield of phthalide (transparent plates), m.p. 72-73°, is 47 g. [Pg.772]

Soft red winter (SRW), which is grown in the eastern third of the United States, is a high yielding wheat, but relatively low in protein, usually about 10%. SRW best provides flour for cakes, pastries, quick breads, crackers, and snack foods. This fall-seeded wheat constitutes about one-quarter of U.S. wheat exports. [Pg.354]

The FD C certified colors are all water-soluble dyes, but can be transformed into insoluble pigments known as lakes by precipitating the dyes with alurninum, calcium, or magnesium salts on a substrate of aluminum hydroxide. The lakes are useful in appHcations that require color whereas in dry form, such as cake mixes, or where water may be present and bleeding is a problem, such as food packaging. FD C Red Lake No. 3 was deHsted in Febmary... [Pg.437]

Aromatic mm is produced on the Island of Java in Indonesia. It derives its unique aromatic character from the addition of dried red Javanese rice cakes to the fermenting mash. After maturating for three to four years, the mm is shipped to Hokand for additional aging prior to blending and bottling. [Pg.83]

Consumers expectations depend on several factors including cultural background, past experiences, desire for color coordination, esthetic appeal, local customs, fads, etc. Thus, eg, a Texas red hot sold ia the South is often colored quite differently than one sold ia the North, Midwesterners prefer butter with a deep yellow color, and on birthdays the decoration on a boy s cake are often blue and those on a gid s are often pink. [Pg.440]

Rouge is a fine red powder of ferric oxide [1309-37-1] (Fe202). It is usually used in the cake form but is also impregnated in paper or cloth known as crocus cloth. [Pg.494]

The turbo-tray dryer can handle materials from thick slurries [1 million (N s)/m (100,000 cP) and over] to fine powders. It is not suitable for fibrous materials which mat or for doughy or tacky materials. Thin slurries can often be handled by recycle of dry product. Filter-press cakes are granulated before feeding. Thixotropic materials are red directly from a rotary filter by scoring the cake as it leaves the drum. Pastes can be extruded onto the top shelf and subjected to a hot blast of air to make them firm and free-ffowing after one revolution. [Pg.1215]

Acriflavin Mixture (Euflavin, 3,6-diamino-lO-metbylacridiniuni chloride) [8063-24-9] M 259.7, m 179-181 . Purified by dissolving in 50 parts of H2O, shake with a small excess of freshly ppted and washed Ag20. The mixture is set aside overnight at 0 and filtered. The cake is not washed. The pH of the filtrate is adjusted to 7.0 with HCl and evaporated to dryness. The residue is then crystd twice from MeOH, twice from H2O and dried at 120 X ,ax at 452nm has a loge value of 4.67. It is a red powder which readily absorbs H2O. The solubility is increased in the presence of proflavin. The dihydrochloride is a deep red crystn powder. It is available as a mixture of 3,6-diaminoacridinium chloride (35%) and its 10-metho-chloride (65%). [see Albert, The Acridines Arnold Press p. 346 1966 Chem Ber 45 1787 1912]. [Pg.94]

For the purpose of washing, the filter cake on the funnel is covered with ice water. After being allowed to remain in contact for a few seconds, the liquid is quickly drained under reduced pressure. The second portion of washing water should no longer be acid to Congo red. [Pg.11]

Monascus is cultivated on solid media in Asian countries to produce a red colorant named Anka and used as a food ingredient. A Chinese medical book on herbs published in the first century first mentioned the terms ang-kak and red mold rice. Red mold rice has been used as a food colorant or spice in cooking. In 1884, the French botanist Philippe van Thieghem isolated a purple mold on potato and linseed cakes and named it Monascus ruber. This ascomycete was so named because it has only one polyspored ascus. In 1895, Went isolated a mold from the red mold rice obtained from a market in Java, Indonesia. This fungus was named Monascus purpureus, after which several other species were isolated around the world. [Pg.413]


See other pages where Red cake is mentioned: [Pg.392]    [Pg.392]    [Pg.796]    [Pg.382]    [Pg.392]    [Pg.392]    [Pg.796]    [Pg.6941]    [Pg.392]    [Pg.392]    [Pg.796]    [Pg.382]    [Pg.392]    [Pg.392]    [Pg.796]    [Pg.6941]    [Pg.469]    [Pg.767]    [Pg.857]    [Pg.18]    [Pg.328]    [Pg.461]    [Pg.165]    [Pg.40]    [Pg.55]    [Pg.1472]    [Pg.597]    [Pg.521]    [Pg.94]    [Pg.412]    [Pg.469]    [Pg.767]   
See also in sourсe #XX -- [ Pg.977 ]

See also in sourсe #XX -- [ Pg.977 ]

See also in sourсe #XX -- [ Pg.42 ]




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