Synthetic red iron oxide

Synthetic Iron Oxides. Iron oxide pigments have been prepared synthetically since the end of the seventeenth century. The first synthetic red iron oxide was obtained as a by-product of the production of sulfuric acid from iron sulfate containing slate. Later, iron oxide pigments were produced direcdy by the thermal decomposition of iron sulfates. In the 1990s, about 70% of all iron oxide pigments consumed are prepared synthetically. 

The largest volume of synthetic red iron oxide is produced by the two-step calcination of iron(II) sulfate. In the first step, the iron(II) sulfate heptahydrate is dehydrated to a monohydrate ... 

Synthetic red iron oxides are prepared in a variety of grades from light to dark. These are sold under a variety of names, eg, Indian red, Turkey red, and Venetian red. 

D 3280 WHITE ZINC PIGMENTS D 3322 PRIMER SURFACES D 3323 SOLVENT/FLAT WALL PAINTS D 3358 WATER BASED FLOOR PAINTS D 3383 SOLVENT/FLOOR PAINTS D 3425 INTERIOR SEMIGLOSS D 3451 POWDER COATINGS D 3619 ANHYDROUS AL-SILICATES D 3721 SYNTHETIC RED IRON OXIDE D 3724 SYNTHETIC BROWN FE-OXIDE... 

This is the largest class of synthetic iron oxide pigments. Synthetic red iron oxide pigment corresponds to the natural mineral hematite. It is prepared by mainly four processes ... 

Iron Oxide Reds. From a chemical point of view, red iron oxides are based on the stmcture of hematite, a-Fe202, and can be prepared in various shades, from orange through pure red to violet. Different shades are controlled primarily by the oxide s particle si2e, shape, and surface properties. Production. Four methods are commercially used in the preparation of iron oxide reds two-stage calcination of FeS047H2 O precipitation from an aqueous solution thermal dehydration of yellow goethite, a-FeO(OH) and oxidation of synthetic black oxide, Fe O. ... 

Like the natural iron oxide pigments, the synthetics are used for colouring concrete, bitumen, asphalt, tiles, bricks, ceramics and glass. They are also used extensively in house and marine paints. Because the shapes of the particles can be accurately controlled and the particle size distribution is narrow, synthetic iron oxides have a greater tinting strength than the natural ones and so, are chosen where paint colour is important, i. e., for top coats. Red iron oxides are used in primers for automobiles and steel structures. 

OSO . piitox] Red and yellow iron oxides synthetic iron oxidm for coatings and plastics natural red iron oxide for highly loaded coatiqgs, primers, industrial maintenance finishes, exterior applies., building inods., rubber, plastics. 

RED BURNT SIENNA BURNT UMBER CALCOTONERED COLCOTHAR COLLOIDAL FERRIC OXIDE FERRIC OXIDE INDIAN RED IRON(in) OXIDE IRON OXIDE RED IRON SESQUIOXIDE JEWELER S ROUGE MARS BROWN MARS RED NATURAL IRON OXIDES NATURAL RED OXIDE OCHRE PRUSSIAN BROWN RED IRON OXIDE RED OCHRE ROUGE RUBIGO SIENNA SYNTHETIC IRON OXIDE VENETIAN RED VITRIOL RED YELLOW OXIDE OF IRON... 

Ferric oxide (1882) n. Fe203. Iron (III) oxide. Stable anhydrous oxide of iron. This constitutes the major ingredient in the chemically prepared synthetic reds. Indian reds, iron oxides, etc., but in the natural red oxides the proportion of ferric oxide varies considerably and is frequently associated with hydrated forms of the oxide. 

Indian red (ca. 1753) n. Natural, Pigment Red 101 (77491). Synthetic Pigment Red 101 (77491). Crystalline copperas (ferrous sulfate in crystal form) is converted by calcinations to ferric oxide, producing a range of light to dark red oxide pigments. The dark shades are known as Indian red. Original Indian reds were a variety of natural red iron oxides obtained from India. 

Single-phase brown oxides of iron can be synthesized by controlled oxidation of black iron oxides. Different tones of brown can be prepared by controlling the oxidation process, and hence controlling the amount of Fe Og (red). Synthetic brown iron oxide is also synthesized by calcination of a-FeOOlT with controlled quantities of manganese compounds. These pigments are not widely used in... 

FuUer (1973) ejqtlains diat diis term refers to synthetic analogues of calcined yellow ochres or goethite (qq.v.) by thermal treatment of synthetic yellow iron oxides a series of red pigments can be produced. These pigments apparently differ from so-caUed copperas reds (thermally decomposed iron(II) sulfate hydrate) by having acicular (needle-like) particle morphology rather than a spheroidal shape. 

Fuller (1973a) describes a number of processes that result in synthetic iron oxides and hydroxides. For red iron oxides he details calcination of iron(II) sulfate hydrate (copperas reds), calcination of synthetic yellow iron oxides (ferrite reds), aqueous precipitation from iron(III) hydroxide nucleation in solutions of iron(II) salts and calcination of magnetite at about 370°C. For... 

A group of synthetically produced iron oxide pigments with colours in the yellow-red-violet-black range, the term typically qualified by a colour descriptor (such as Mars red ). The mars colours emerged in the eighteenth century. 

Heaton (1928) describes Turkey red pigments as Ughter shades of synthetically produced iron oxides obtained by calcination of iron salts at low to medium temperatures. 

Red iron oxides [natural and synthetic ferric oxide (Fe203)] [AI2O2, Si02, 2H2O Fc203 arui Fe203]. Haematite is the red iron oxide available in earth s crust. The synthetic type has an excellent resistance to chemicals. It has excellent opacity and light fastness. 

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. 

Iron Oxides. In addition to the black iron oxide, there are several natural and synthetic yellow, brown, and red oxides. As a class, they provide inexpensive but dull, lightfast, chemically resistant, and nontoxic colors. The natural products ate known as ocher, sieima, umber, hematite, and limonite. These include varying amounts of several impurities in particular, the umbers contain manganese. Their use is limited because of low chroma, low tinting strength, and poor gloss retention. 

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