Ferrous titanate

The hberated iodine, as the complex triiodide ion, may be titrated with standard thiosulfate solution. A general iodometric assay method for organic peroxides has been pubUshed (253). Some peroxyesters may be determined by ferric ion-catalyzed iodometric analysis or by cupric ion catalysis. The latter has become an ASTM Standard procedure (254). Other reducing agents are ferrous, titanous, chromous, staimous, and arsenite ions triphenylphosphine diphenyl sulfide and triphenjiarsine (255,256). 

The liberated iodine may be titrated using std thiosulfate soln, or, in trace analysis, detd by spectrophotometric methods. Other reducing agents commonly used in peroxide analysis are hydriodic acid, ferrous, titanous, stannous, and arsenious ions. Also (recently), triphenylphos-phine, which is oxidized to triphenyl phosphine oxide. The excess triphenyl phosphine may be detd gravimetric ally, tit rime trically, or spectro-photometrically... 

Note 3 The explosive oils may be analyzed for nitrate mcro en uiiu nicro uirro Li by the ferrous-titanous procedure described in Ref 11, PP1384 1391... 

Requirements and tests for Pyroxylin type NC are described in Specs listed here as Refs 51 52 and for Technical NC(for use in organic coatings) in Ref 53. Several US std tests are described in Ref 55. In Ref 49 is described detn of N content of NC by IR spectrophotometry and in Ref 55 detn of NC by chromous chloride reduction. One of the latest methods on detn of N content in NC by ferrous-titanous titration is described in Ref 44. This test will be included in the next edition of US Military Standard Spec... 

Detn of N in NC by ferrous-titanous titrimetric method) 37)S.Sandi G.Flanquart, ChimAnal(Paris) 39, 20-4(1957) CA 51, 7943 (1957)(Detn of N in NC, NG, PETN, etc by titration with ferrous sulfate soln using the dead-stop end point method) 38)Y.Lacroix er al, MP 39, 459-68(1957) CA 52, 19688(1958)... 

Certain difficulties in the application of titania enamels arise as a result of their reduced colour stability. Even small amounts of Fe cause undesirable yellow colouring. Of some help is oxidation to Fe which does not form the ferrous--titanate colouring complex. Similar unfavourable efiects are also exhibited by other impurities (Cr, Ta, >Jb, W). 

Hydroxylation by the Metal lon—Oxygen Systems. A monosubsti-tuted benzene was suspended in aqueous solution of a metal salt through which oxygen was bubbled. Two aromatic compounds (toluene and anisole) were treated this way with each of four metal salts (ferrous sulfate in the presence of EDTA, titanous chloride, cuprous chloride and stannous pyrophosphate) a third compound (fluorobenzene) was oxidized with the ferrous, titanous, and cuprous systems, and a fourth aromatic compound (nitiobenzene) was treated with ferrous ion with EDTA. The initial concentration of the metal ion was varied. 

Metal Ion-Oxygen Systems. Hydroxylation of aromatic compounds occurs during the autoxidation not only of ferrous ion but also of other metal ions. The ions we have investigated are all capable of undergoing one-electron oxidation. [This is well known for ferrous, titanous, and cuprous ions and has recently been demonstrated also for stannous ion (43).] The main problem in elucidating the course of the hydroxylations is determining the nature of the hydroxylating species. 

The principal ore of titanium is ilmenite or ferrous titanate (FeTiOa), and this is the ore mainly used for the production of ferrotitanium by a smelting process. However, its use directly for the production of titanium tetrachloride would be extremely wasteful of chlorine, since a high proportion of this reagent would be used for the production of unwanted ferric chloride. Consequently, chlorination generally involves the less plentiful ore of titanium, rutile, the dioxide (TiOa), which is found in the form of black river and beach sands. This is mixed with ground charcoal or petroleum coke, briquetted, and volatile material removed by heating to 500 to 800°C. Chlorination can be carried out at 700 to 1000°C in a conventional vertical furnace, and the reaction is sufficiently exothermic for it to proceed without the application of external heat, except to raise the temperature of the reactants initially. The reaction may be represented approximately as ... 

Ilmenite. Ferrous titanate, Fe0.Ti02 m.p. 1365°C. This mineral is the principal constituent of the heavy minerals in the beach sands of Australia and elsewhere it is thus the chief source of titania, which is used in the ceramic industry as an opaciher and as a constituent of some ceramic dielectrics. Image Furnace. Apparatus for the production of a very high temperature in a small space by focusing the radiation from the sun (solar furnace) or from an electric arc (arc-image furnace) by means of mirrors and/or lenses. Such furnaces have been used for the... 

Ammonium fluoride 45 230-266 110-130 - - - - plus suspended ferrous titanate (ilmenite)... 

Titanium dioxide is also produced from ilmenite. Ilmenite is also termed ferrous titanate (FeTiOg). It is reacted with sulfuric acid. The temperature of the reaction is maintained in the range of 150°C-180°C. The result of this... 

Iron Titanates. Ferrous metatitanate [12168-52-4] FeTiO, mp ca 1470°C, density 472(0), an opaque black soHd having a metallic luster, occurs in nature as the mineral ilmenite. This ore is used extensively as a feedstock for the manufacture of titanium dioxide pigments. Artificial ilmenite may be made by heating a mixture of ferrous oxide and titanium oxide for several hours at 1200°C or by reducing a titanium dioxide/ferric oxide mixture at 450°C. 

Ferrous orthotitanate [12160-20-2] Fe2Ti04, is orthorhombic and opaque. It has been prepared by heating a mixture of ferrous oxide and titanium dioxide. Ferrous dititanate [12160-10-0] FeTi20, is orthorhombic and has been prepared by reducing ilmenite with carbon at 1000°C. The metallic ion formed in the reaction is removed, leaving a composition that is essentially the dititanate. Ferric titanate [1310-39-0] (pseudobrookite), Fe2TiO, is orthorhombic and occurs to a limited state in nature. It has been prepared by heating a mixture of ferric oxide and titanium dioxide in a sealed quartz tube at 1000°C. 

Redox (reduction-oxidation) titrimetry is used primarily for nitrate detns. Five systems are in current use ferrous sulfate—dichromate, io dome trie, periodic acid oxidation (NaOH titrant), K permanganate, and titanous chloride-ferric ammonium sulfate. The ferrous sulfate— dichromate system is used for MNT DNT detns (Vol 2, C162-Lff Vol 6, F17-Rff Ref 17). In the iodometric procedure, the sample (ie, NG) is treated in a C02 atm with a satd soln of Mn chloride in coned HC1, the vol reaction products are bubbled thru a K iodide soln, and the liberated iodine is titrated with standard thiosulfate soln (Refs 1 17). The periodic... 

The prescribed analytical method for determining nitrogen content in PETN is the MIL-STD-286 Method 209.3. The ferrous chloride-titanous chloride method described for NG in Vol 6, G106-7 is also applicable to PETN... 

Note It has been claimed in the Progr Rept 20-365 that none of the existing methods of reduction of nitrate by titanous ion are accurate when analyzing AN. The modification proposed in the rept is not as accurate as ferrous sulfate or other methods and for this reason cannot be recommended References on Ammonium Nitrate> Analytical Procedures ... 

Oxidation processes involving the subsequent titration of an excess of ferrous sulphate,2 oxalic acid (in the presence of silver sulphate as catalyst), titanous chloride,4 or of the quantity of iodine liberated from potassium iodide,5 are also available but are less satisfactory. In the last-named method a large excess of potassium iodide is necessary to obtain complete reaction in a short time. The reaction may be accelerated by the addition of potassium chloride6 or ammonium chloride with 20 per cent, by weight of the latter salt present a large excess of the iodide is not necessary and the liberated iodine may be titrated after fifteen minutes.7... 

Diazotization has been reported for all the pyrazolopyridines, and in some cases the salts have been isolated. A 7-aminopyrazolo[4,3-c]pyridine (191a) was converted to the corresponding hydroxy compound with sodium nitrite in hot glacial acetic acid.159 Analogous products were obtained from a 3-aminopyrazolo[3,4-b]-15 and 2-aminopyrazolo[l,5-a]pyridine.186 Decomposition of diazonium salts with hydrobromic acid afforded 3-bromo-pyrazolo[3,4-c]-u0 or -[4,3-bjpyridines111 deamination of 3-aminopyra-zolo[3,4-h]pyridines was achieved via treatment of the diazonium salts with hypophosphorous acid,10 titanous chloride,238 or ferrous ammonium sulfate.238 Kocevar et al.236 have made a detailed study of the reactions of the latter diazonium salt. 

PEROVSKITE. The mineral perovskite is calcium titanate, essentially CaTiCL, with rare earths, principally cerium, proxying for Ca, as do both ferrous iron and sodium, and with colunibiuni substituting for titanium, ll crystallizes in die orthorhombic system, but witli pseudo-isometric character fracture subconchoidal to uneven brittle hardness, 5.5 specific gravity. 4 luster, adamantine color, various shades of yellow to reddish-brown or nearly black transparent to opaque. It is found associated with chlorite or serpentine rocks occurring in the Urals, Baden, Switzerland, and Italy, It was named for Von Perovski. 

Other typical reagents generated for coulometric titrations are hydrogen and hydroxyl ions, redox reagents such as ceric, cuprous, ferrous, chromate, ferric, manganic, stannous, and titanous ions, precipitation reagents such as silver, mercurous, mercuric, and sulfate ions, and complex-formation reagents such as cyanide ion and EDTA [8-10]. 

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