Abstract:
PURE AQUEOUS SOLUTION OF POTASSIUM HEXACYANOFERRATE (III), SODIUM HEXACYANOFERRATE (III) AND SODIUM POTASSIUM HEXACYANOFERRATE (III) ARE PREPARED BY OXIDATION OF THE CORRESPONDING HEXACYANOFERRATE (II) SOLUTIONS WITH ACIDS CONTAINING THE GROUP (FE(CN)6) AND AN OXIDIZING AGENT HAVING AN OXIDATION POTENTIAL GREATER THAN +0.46 VOLT.
Abstract:
Metal silicates of Groups II to IV of the periodic system are hydrophobized by treating an aqueous suspension of the silicate with an organohalosilane with intensive stirring at 15* to 70* C. The precipitate is then filtered, washed, dried and tempered at 200* to 500* C.
Abstract:
Alkali ferrocyanides are prepared by converting calcium hexacyanoferrate (II) with an iron (II) salt to an iron (II) hexacyanoferrate (II), washing the complex with water until free of calcium ions and then reacting further with sodium, potassium or ammonium cyanide.
Abstract:
Berlin blue is produced by converting (a) calcium ferrocyanide, sodium ferrocyanide or magnesium ferrocyanide with (b) an iron II salt at a pH below 7 to an acidic iron II salt of ferrocyanic acid FeH2(Fe(CN)6). The calcium or sodium ions can be washed out of the precipitate of the ferrocyanic salt. The precipitate is treated with (c) an inorganic or organic potassium salt to form Berlin white and then oxidized to Berlin blue. Alternatively, (a), (b) and (c) can be reacted together at a temperature of 20* to 60*C. to form Berlin white directly.
Abstract:
Voluminous precipitates or suspensions are contacted countercurrently with liquid purification or extraction agents that hold the continuously supplied precipitate or suspension in the upwardly flowing liquid in a kind of fluidized bed. A suitable apparatus is also described.
Abstract:
An animal feed composition on the basis of a milk exchange material comprises, in addition to dry skimmed milk, animal and/or vegetable fats, emulsifying agent and nutrients an amount between 0.5 and 10 percent by weight relative to the total composition of a finely divided synthetic silicic acid. The addition prevents caking of the composition and improves the flow properties.
Abstract:
Berlin blue prodn. by reacting a ferrocyanide with a Fe(II) salt in an aq. medium having pH 7; converting the resulting acid salt into Berlin white by reaction with an inorg. or org. potassium salt at pH of 1 (or less) to 6; and oxidising this prod. to Berlin blue; is improved by using Mg2 Fe(CN)6 as a ferrocyanide. The reaction between Mg2 Fe(CN)6 and a Fe(II) salt can be carried out in an only slightly acidic medium so that there is no need to use an appts. made from a highly anti-corrosive matl. FeSO4 can be used as a Fe(II)-salt, because it does not form any insoluble salt with Mg. The quality of the prod. is good.