Chromium fluorides

Cr(02CCH3)2]2,2H20. Red insoluble compound formed from sodium ethanoate and CrC)2 in aqueous solution. The most stable Cr(II) compound contains a Cr —Cr bond, chromium fluorides... 

The higher chromium fluorides, CrFstrong oxidizing agents, immediately hydrolysed by water,... 

Mordant Dyes. MetaUizable azo dyes are appHed to wool by the method used for acid dyes and then treated with metal salts such as sodium chromate [7775-11-5] sodium dichromate [10588-01-9] and chromium fluoride [1488-42-5] to form the metal complex in situ. This treatment usually produces a bathochromic shift ia shade, decreases the solubUity of the coloring matter, and yields dyeiags with improved fastness properties. The chromium salts can be appHed to the substrate before dyeiag (chrome-mordant or chrome-bottom method), together with the dye ia a single bath procedure (metachrome process), or as a treatment after dyeiag (afterchrome process). 

Chromic Acid Electrolysis. Alternatively, as shown in Figure 1, chromium metal may be produced electrolyticaUy or pyrometaUurgicaUy from chromic acid, CrO, obtained from sodium dichromate by any of several processes. Small amounts of an ionic catalyst, specifically sulfate, chloride, or fluoride, are essential to the electrolytic production of chromium. Fluoride and complex fluoride catalyzed baths have become especially important in recent years. The cell conditions for the chromic acid process are given in Table 7. 

It may also be prepared by pyrolysis of 1,1-difluoroethane at 725°C over a chromium fluoride catalyst in a platinum tube or by the action of zinc dust on bromodifluoroethane at 50°C. 

Fluor-, of or combined with fluorine, fluoro-, fluo-, fluoride of (see instances following),. ammonium, n. ammonium fluoride, -an-thenchinon, n. fluoranthenequinone. -anti-mon, n. antimony fluoride, -arson, n. arsenic fluoride, -baryum, n. barium fluoride, -benzol, n. fluorobensene, fluobenaene. -bor, n. boron fluoride. -borsMure, /. fluo-boric acid. -brom, n. bromine fluoride, -chrom, n. chromium fluoride, -eisen, n. iron fluoride. 

For formation of anticorrosive and adhesion-improving protective layers on metals the cleaned surface is treated with aqueous acidic solution containing molybdate, chromium fluoride, phosphate, acetate, and Zn ions. As dispersant a mixture of 60% alkali salt of a phosphate ester, 20% alkylpolyglucoside, and 20% fatty alcohol ethoxylate was applied. This method passivates the metal surface by formation of an anticorrosive and protective layer that improves adhesion of subsequent coatings. 

Galvez, J.L., Dufour, J., Negro, C., and Lopez-Mateos, F. Determination of iron and chromium fluorides solubility for the treatment of wastes from stainless steel mill, Chem. Eng. J., doi 10.1016/j.cej 03.014, 2007. 

Welding Fumes, gases oxides of cadmium, chromium, fluorides, iron, manganese, nickel, nitrogen, vanadium, by-products from fluxes, coatings, electrodes... 

These are classified as those with a requirement below one pg (microgram) per day. Elements in this class include boron, chromium, fluoride, iodine, molybdenum, nickel, selenium, cobalt and manganese. Cobalt is part of vitamin (see above). However, there appear to be no recommended dietary intakes for any of these except molybdenum. 

One of the most useful ways of introducing fluorine into organic compounds is the replacement of the hydroxyl group in alcohols hydroxy compounds, and carboxylic acuis Methyl alcohol reacts with anhydrous hydrogen fluoride at 100 500 °C in the presence of aluminum fluoride [60, 61], zinc fluoride [62] chromium fluonde [63], or a mixture of aluminum and chromium fluorides [64] to give a 20-78% yield of fluoromethane Attempted fluonnations of higher alcohols by this method failed [60]... 

Yield.—70—80% theoretical (70—-80 gms.). Dyes wool brown with chrome mordants, chromium fluoride giving the best shades. (J. S. C I, 3, 141.)... 

A solution containing 10% of chromium fluoride and 5% of sodium acetate. 

From the results of these and other subsequent tests—in some cases that with chromium fluoride solution (11)—the nature of the colouring matter is decided in accordance with Table XLIV on p. 427. 

With each of these four groups the procedure is as described later. In the first place, however, the colouring matter is investigated with reference to its tintorial properties by means of dyeing tests on non-mordanted cotton or wool, on wool mordanted with aluminium sulphate and cream of tartar, on wool mordanted with chromium fluoride and cream of tartar, on cotton mordanted with tannin and then with tartar emetic, on cotton mordanted with aluminium acetate and on cotton mordanted with chromium acetate. 

Basic mordant colouring matters (gallocyanin, etc.), if treated with salted caustic soda and then with formic acid, behave like basic colouring matters, except that they are extracted less completely. The acid extracts give with tannin a finer and less distinct precipitate. To distinguish them from ordinary basic colouring matters use is made of the fact that they are precipitated by chromium fluoride. 

Chromium fluoride (10 grams of chromium fluoride and 5 grams of sodium acetate in 100 c.c of water). 

Wisconsin Johnson Matthey, Inc., Alfa Aesar, Ward Hill, Massachusetts (6) chromium(III) chloride Blue Grass Chemical Specialties, LP, New Albany, Indiana, McGean-Rohco, Inc., Cleveland, Ohio (7) chromium diboride Johnson Matthey, Inc., Ward Hill, Massachusetts (8) chromium dioxide DuPont, DuPont Diversified Businesses, Newport, Delaware (9) chromium 2-ethylhexanoate OM Group, Inc., Franklin, Pennsylvania, The Shepherd Chemical Company, Cincinnati, Ohio (10) chromium fluoride Atotech... 

Antimony, arsenic, barium, boron, chromium, fluoride, manganese, mercury, molybdenum, nitrate, sodium, sulfate... 

Sualitative analysis of the screw heads did show the corroded film on Le screws was the metal fluorides. New screws were used in each run, and the necessary thermal corrections were made on the data for this side reaction. The deficiency of HF was used to make these corrections which amounted to the formation of roughly 0.0015 mole of iron and chromium fluorides. Since the AHf° of iron and chromium fluorides are nearly the same, the correction was made assuming only the formation of iron fluoride (AH/0 = —177.8 kcal./mole). As an additional check, an OF2-H2 run was made with the stainless steel screws replaced by nickel-... 

O2CI2N2RUC12H8, Ruthenium(II), dicarbo-nyldichloro(2,2 -bipyridine)-, 25 108 02CrF2, Chromium fluoride oxide, 24 67 O2F2U, Uranium(VI), difluorodioxo-,... 

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