Blended red oxides of iron

BLENDED RED OXIDES of IRON (1309-37-1) Violent reactions with powdered aluminum (thermite reaction), hydrogen peroxide, calcium disilicide (thermite reaction), ethylene oxide (may cause explosive polymerization), calcium hypochlorite, hydrazine, hydrogen trisulfide, powdered magnesium. Incompatible with powdered calcium carbide, carbon monoxide, chlorides, guanidinium perchlorate, metal acetylides. Contact with the explosive hydrazinium diperchlorate or ammonium perchlorate can be made more heat-, shock-, or friction-sensitive. Incompatible with aluminum-magnesium-zinc alloys. 

Synonyms cas 1309-37-1 bauxite residue black oxide of iron blended red oxides of iron Burntisland... 

Iron Browns. Iron browns are often prepared by blending red, yellow, and black synthetic iron oxides to the desired shade. The most effective mixing can be achieved by blending iron oxide pastes, rather than dry powders. After mixing, the paste has to be dried at temperatures around 100°C, as higher temperatures might result in the decomposition of the temperature-sensitive iron yellows and blacks. Iron browns can also be prepared directiy by heating hydrated ferric oxides in the presence of phosphoric acid, or alkaU phosphates, under atmospheric or increased pressure. The products of precipitation processes, ie, the yellows, blacks, and browns, can also be calcined to reds and browns. 

Brown oxides are manufactured either by blending mixtures of the red, yellow, and black oxides or by precipitation of an iron salt with alkaU followed by partial oxidation of the precipitate. The result is a mixture of red Fe202 [1309-37-1] and black Fe O [1309-38-2] FeO Fe202-... 

Transparent yellow iron oxide has the a-FeO(OH) (goethite) structure on heating it is converted into transparent red iron oxide with the a-Fe203 (hematite) structure. Differential thermogravimetric analysis shows a weight loss at 275 °C. Orange hues develop after brief thermal treatment of yellow iron oxide and can also be obtained by blending directly the yellow and red iron oxide powders. 

Colour correction of cutaneous preparations that have a covering colour (zinc oxide or titanium dioxide), may be desired for cosmetic reasons. The colour of the skin can be approximated by a mixture of ferric oxides. Zinc oxide mixtures can be made skin coloured with a mixture of yellow, red and brown or yellow, red and black ferric oxide. Because of the large variation in skin colours it is only possible to give some suggestions for such mixtures. For instance for 100 mL zinc oxide cutaneous suspension, 1 g of an iron oxide concentrated orange-like blend (Table 12.14) will probably do. 

The oldest known use of paint dates to approximately 23,000 BC in the eave paintings near Lascaux, France. These drawings were made with pastes of natural iron oxides and manganese oxides ground with crude mortars and pestles and mixed with water. Egg whites, animal fat, or marrow were possible binders. Wood ash, siderite (iron carbonate), and chalk may have been used as well to round out the primitive color palette of black, red, yellow and blends thereof. 

Iron oxides, which were undoubtedly components of these prehistoric paints, still find application today as low-cost, low-toxicity pigments in paint, plastics, rubbers and cosmetics. The three main colours available are red (haematite-, Fe203), yellow (goethite FeO.OH) and black (magnetite-, Fe304), and other colours can be produced by blending these three. The oxides are generally prepared by precipitation from aqueous solution ... 

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