Yellow prussiate of potash

Synonyms potassium hexacyanoferrate(II) tetrapotassium hexakis(cyano-C)ferrate(4—) yellow prussiate of potash... 

Tetrapotassium hexakiscyanoferrate trihydrate [14459-95-1], K4[Fe(CN)J H20, is an efflorescent lemon yellow compound known as yellow prussiate of potash. The anhydrous material [13943-58-3] is obtained at 70°C. The compound is soluble in water and acetone, but insoluble in alcohol, ether, and ammonia. It is oxidized to hexakiscyanoferrate(3—) by oxygen in acidic solution, or by oxidants such as ozone, C, Br2, H202, or MnO. A large number of insoluble or slightly soluble mixed salts of the general formula K2MII[Fe(CN)(5] and KMIII[Fe(CN)(5] are known, eg, M11 = cobalt(II)... 

Synonyms Ferrocyanide of potash, Yellow prussiate of potash. 

Potassium ferrocyanide, K4Fe(CN)6.3H20, is the most important salt of ferrocyanic acid, and is known in commerce by the more familiar name of yellow prussiate of potash.1 It results when a solution of... 

Porrocyanido of potassium (yellow prussiate of potash) gives a nearly white precipitate, becoming gradually blue in tho aV, and immediately 80 on tho addition of a little weak nitric acid or chlorino water. 

Potassium Ferrocyauide. Tetrapotassium hexakis-(cyano-C)ferrate(4 —) potassium hexacyanoferrate(II) yellow prussiate of potash. C6FeK4N4 mol wt 368.34. C 19.56%, Fe 15.16%, K 42.46%, N 22.82%. K4Fe(CN)(. Re-view of properties, chemistry and syntheses The Chemistry of Ferrocyanides, American Cyanamid Co. Beacon Press, New York, 1953) 112 p. 

Potassium Ferrocyanid—Yellow prussiate of potash—Potassii ferrocyanidum (U.S.)—Potassse prussias Hava (Br.)—K4[Fe(CN)i,J -)- 3 Aq—867.9 -F 54.—This salt, the source of the other cyanogen compounds, is-manufactured by adding organic matter (blood, bones, hoofs, leather, etc.) and iron to KjCOa in fusion or by other processes in which the N is obtained from the residues of the purification of coal-gas, from atmospheric air, or from am-inoniacal compounds. 

Tetrapotassium ferrocyanide Tetrapotassium hexacyanoferrate Tetrapotassium hexacyanoferrate (II) Tetrapotassium hexacyanoferrate (4-) Yellow prussiate of potash... 

Yellow prussiate of calcium Yellow prussiate of lime. See Calcium ferrocyanide Yellow prussiate of potash. See Potassium ferrocyanide... 

The term is generally used to refer to Prussian blue precipitated onto a barium sulfate, baryte (qq.v.) or similar base. Davidson (1880) says of Brunswick, Celestial and damp blues Brunswick or Celestial Blue is made by precipitating the alumine from a solution of alum by carbonate of soda, washing the precipitate, and adding sulphate of baryta, sulphate of iron, yellow prussiate of potash, and some bichromate of potash. When dried, this mixture is known as Brunswick or celestial blue but when the sulphate of baryta is left out, and the material is not dried, it is called damp blue. Heaton (1928) lists Bnmswick blue as a current synonym, a reduced Prussian blue . Mayer (1991) also indicates that it may contain some ultramarine blue (. v.). 

Salter (1869) discusses a pigment which he calls cobalt Prussian blue, although he reports that it was not in ordinary use. It appears to be essentially Prussian blue (q.v.) with the iron(III) replaced by cobalt (Fe replaced by Co " ), prepared by mixing yellow prussiate of potash. .. with a solution of oxalate of sesquioxide of cobalt . Salter further noted that it was described by Gmelin, but reported the product is. .. a dingy slate colour . 

Supposedly there was also a wet process involving mixing a dilute solution of cupric sulphate and ferrous sulphate, in proper proportions. .. with a quantity of ferrocyanide of potassium, not in excess (Salter, 1869), though clearly this is giving one of the copper hexacyanofenate(II) pigments copper dipotassium hexacyanoferrate(II) or dicopper hexacyanoferrate(II) hydrate. Terry (1893) also discriminates between Prussian black (calcined Prussian blue) and Prussiate black, the carbonaceous residue from making yellow prussiate of potash . 

Terry (1893) discriminates between Prussian black (calcined Prussian blue qq.v.) and Prussiate black, the carbonaceous residue from making yellow prussiate of potash . 

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