Red ferric oxide

Over time and at the relatively high temperatures involved in the steam-CR system, some red ferric oxide is also formed from ferric... 

The presence of red ferric oxide usually indicates an inactive pit but black oxide infers active pitting. Condensate receivers are common points for oxygen infiltration (especially in smaller boiler plants). 

FeS04 + 6H20 + 02 = 4FeOOH + 4H2S04 The pigment can be used in this form, or calcined to a red ferric oxide pigment. 

Although most pharmaceutical colorants in use today are of synthetic origin, a few are obtained from natural mineral and plant sources. For example, red ferric oxide is mixed in small proportions with zinc oxide powder to prepare calamine, giving the latter its characteristic pink color, which is intended to match the skin tone upon application. 

Ferrous sulphide has a bluish black appearance, reminiscent of that of magnetic oxide, but it is not magnetic. Density 4 67. It is stable when heated in hydrogen or in the absence of air, but when heated in air it readily oxidises to ferrous sulphate, whilst at red heat all the sulphur is expelled, red ferric oxide remaining. 

Fretting is of course not a form of corrosion, but it is often confused with corrosion, and can sometimes be associated with serious corrosion. It is in fact a form of oxidative wear which occurs when solid surfaces, usually metallic, rub together in a low-amplitude oscillation. The damage can be very severe. With metals it is characterized by pitting which resembles corrosion, and with ferrous metals there is a characteristic production of red ferric oxide. 

Indian red. (iron saffron). A red (maroon) pigment made by calcining copperas to obtain red ferric oxide. Fine particle size. 

A clear orange-red ferric oxide sol flows out of the bottom, in striking contrast to the almost colorless influent. 

Trade Names Containing Aqueous Pigment 50-9430 Colormatch ED-70272 Colormatch ED-70273 Colormatch EDC-70411 See also Iron oxide red Ferric oxide... 

Pigment red 102. See Iron oxide red Ferric oxide Pigment red 104... 

Indian Red. A red ferric oxide pigment made by calcining ferrous sulphate. Indiana Method. A technique for the determination of the quantity of entrained air in concrete on the basis of the difference in the unit weights of a concrete sample with and without air. The name derives from the fact that air-entrained cement was first used to any extent in Indiana, USA. (Proc. A.S.T.M., 47, 865,1947.)... 

Istra. Trade-name a high-alumina CEMENT (q.v.) made in Yugoslavia. Italian Red. One of the red ferric oxide pigments. 

Fig. 11.30 Infrared spectra of (a) red ferric oxide (Fe203) and (b) yellow ferric oxide (Fe203 H2O).

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