Anhydrous iron oxide

As shown in Figure 2, adsorption of dispersants on particle surfaces can increase 2eta potential further, enhancing electrostatic repulsion. Increased repulsion between particles is evidenced by lower viscosity in concentrated slurries, or decreased settling rates in dilute suspensions. The effect of added dispersants on settling of (anhydrous) iron oxide particles is shown in Figure 3. 

Anhydrous calcium sulfate Anhydrous gypsum. See Calcium sulfate Anhydrous iron oxide. See Ferric oxide Anhydrous lanolin. See Lanolin... 

CAS 1309-37-1 (anhyd.) EINECS/ELINCS 215-168-2 Synonyms Anhydrous iron oxide Cl 77491 Colloidal feme oxide Ferric oxide red Ferrosoferric oxide Iron (III) oxide Iron oxide red Iron s uioxide Natural iron oxides Natural red oxide Pigment brown 6 Pigment brown 7 Pigment ted 101 Pigment red 102 Red iron oxide R iron Irioxide Yellow ferric oxide Classificatbn Inorganic color syn. iron oxide Emprical FCiOj... 

Anhydrous hydroiodic acid. See Hydriodic acid Anhydrous iron oxide. See Ferric oxide Anhydrous Lanolin Grade 1, Anhydrous Lanolin Grade 2 Anhydrous Lanolin HP-2050 Anhydrous Lanolin P.80-, Anhydrous Lanolin P95 RA Anhydrous Lanolin P95, Anhydrous Lanolin Superfine, Anhydrous Lanolin Technical, Anhydrous Lanolin USP Cosmetic AA, Anhydrous Lanolin USP Cosmetic, Anhydrous Lanolin USP Deodorized AAA, Anhydrous Lanolin USP Superfine] Anhydrous... 

Synonyms Anhydrous iron oxide Cl 77491 Colloidal ferric oxide Ferric oxide red Ferrosoferric oxide... 

Gleitzer C (1997) Electrical properties of anhydrous iron oxides. In Electrical Properties of Oxide Materials, Key Engineering Materials, 125-126, 355-417 Gleitzer C, Nowotny J, Rekas M (1991) Surface and bulk electrical properties of the hematite phase Fe203. Appl Phys A Mat Sci Proc 53 310-316... 

Anhydrous FeF is prepared by the action of Hquid or gaseous hydrogen fluoride on anhydrous FeCl (see Iron compounds). FeF is insoluble in alcohol, ether, and ben2ene, and sparingly soluble in anhydrous HF and water. The pH of a saturated solution in water varies between 3.5 and 4.0. Low pH indicates the presence of residual amounts of HF. The light gray color of the material is attributed to iron oxide or free iron impurities in the product. 

Wet preparation of red iron oxides can involve either a hydrothermal process (see Hydrothermal processing) or a direct precipitation and growth of iron oxide particles on specially prepared nucleating seeds of Fe202- In the hydrothermal process, iron(II) salt is chemically oxidized to iron(III) salt, which is further treated by alkahes to precipitate a hydrated iron(III) oxide gel. The gel can be dehydrated to anhydrous hematite under pressure at a temperature around 150°C. 

Aluminium fluoride (anhydrous) [7784-18-4] M 84.0, m 250°. Technical material may contain up to 15% alumina, with minor impurities such as aluminium sulfate, cryolite, silica and iron oxide. Reagent grade AIF3 (hydrated) contains only traces of impurities but its water content is very variable (may be up to 40%). It can be dried by calcining at 600-800° in a stream of dry air (some hydrolysis occurs), followed by vacuum distn at low pressure in a graphite system, heated to approximately 925° (condenser at 900°) [Henry and Dreisbach J Am Chem Soc 81 5274 1959]. 

To a mixture of 100 ml of liquid ammonia and about 80 mg of black iron oxide was added 0.78 g (0.02 atom) of potassium. When all of the potassium had reacted, 3.3 g of N,N-dimethyl-N -(2-pyridyl)ethylenediamine was added. After the addition of 75 ml of dry toluene the ammonia was removed on the steam bath. To the cooled and stirred mixture was added 4.26 g of p-chlorobenzyl chloride, and the reaction mixture was stirred on the steam bath for 11 hours. It was then filtered and concentrated to an oil. This concentrate was taken up in ether, and the ethereal solution was washed with water, dried over sodium sulfate, and concentrated. Distillation gave 2.96 g of yellow liquid. Treatment of this distillate with an equivalent quantity of hydrogen chloride in absolute alcohol and precipitation by the addition of anhydrous ether gave 2.33 g of the N,N-dimethyl-N -(4-chlorobenzyl)-N -(2-pyridyl)ethylenediamine hydrochloride. 

Immense deposits of a variety known as red fossil ore occur in the United States, containing from 30 to 50 per cent, of iron and from 0-4 to 0 7 of phosphorus. Red ochre is another form of anhydrous ferric oxide, but the term is also used for a variety of turgite. 

When iron is attacked by fused sodium peroxide, dark red, tabular crystals of a monohydrate, Fe203.H20, are obtained, of density 3 8 at 27° C. The hydrate is magnetic, and when heated to low redness a magnetic form of anhydrous ferric oxide is obtained.3... 

Gravimetric Methods.—If the iron is already in solution, it is first oxidised to the ferric condition and precipitated as ferric hydroxide by addition of ammonia to the boiling solution. The precipitate is well washed, dried in an oven, ignited in a crucible, and weighed as anhydrous ferric oxide, Fe203. 

The sequence of decarbonation processes is determined by the presence of iron oxides (hematite) and the water content of the fluids. In pure anhydrous siderite-chert rocks with an excess of quartz the following transformations... 

I. Preparation of Reduced Iron (Cobalt, Nickel) (245). 2. Pr ara-tion of Pyrophoric Iron (246). 3. Preparation of Iron(II) Oxide (246). 4. Preparation of Macrocrystalline Iron(III) Oxide (246). 5. Preparation of Nickel(III) Oxide (247). 6. Preparation and Properties of Sodium Ferrite (247). 7. Preparation of Anhydrous Cobalt (Nickel) Chloride in an Ethanol Solution (247). 8. Preparation of Anhydrous Iron(IlI) Chloride in a Fluidized Bed (247). 9. Preparation of Potassium Trioxalatoferrate(III) (247). 10. Preparation of Tetraamminecarbonatocobalt(III) Nitrate (248). 

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