Fluorine boric oxide

BF3 is used extensively as a catalyst in various industrial processes (p. 199) and can be prepared on a large scale by the fluorination of boric oxide or borates with fluorspar and concentrated H2SO4 ... 

Borides are relatively inert, especially to non-oxidizing reagents. They react violently with fluorine, often with incandescence. Reaction with other halogens is not as violent and may require some heat. Resistance to oxidation, acids, and alkalis is summarized in Table 17.5. In oxidation conditions, a layer of boric oxide is formed on the surface which passivates it to some degree. Boric oxide melts at 450°C and vaporizes at 1860°C. It offers good protection up to 1500°C in a static environments but it has low viscosity at these temperatures and tends to flow under stress and the protection it offers is limited.f k l... 

Enamels - [BARIUMCOMPOUNDS] (Vol3) - [ALUMINUMCOMPOUNDS - ALUMINIUMOXIDE(ALUMINA) - CALCINED,TABULAR, AND ALUMINATE CEMENTS] (Vol2) - [TIN COMPOUNDS] (Vol 24) -aluminum fluoride in [FLUORINE COMPOUNDS,INORGANIC - ALUMINUM](Vol 11) -antimony compds in [ANTIMONY COMPOUNDS] (Vol 3) -borate in [BORON COMPOUNDS - BORON OXIDES, BORIC ACID AND BORATES] (Vol 4) -boric oxide in prepn of [BORON COMPOUNDS - BORON OXIDES, BORIC ACID AND BORATES] (Vo 14) -lithium for [LITHIUM AND LITHIUM COMPOUNDS] (Vol 15)... 

Boron forms strong bonds to fluorine (644kJmol ), usually combining with three or four fluorides in its compounds or salts. Several binary fluorides of boron are known including boron trifluoride, BF3, a stable gas of great industrial importance as a Lewis acid. Boron trifluoride is synthesized industrially by reaction of hydrofluoric acid with borates or boric oxides (equation 42). ... 

Basically all methods of preparation of boron trifluoride entail the reaction of a boron compound with a fluorine containing compound in the presence of an acid. In one major method of commercial preparation, boron trifluoride is produced from boric oxide and hydrofluoric acid (in the reaction B2O3 + 6HF -> 2BF3 + 3H2O) the product is purified and compressed before packaging in cylinders. Other methods of manufacture employ reactions between boron trichloride or boric and hydrofluoric acid. 

The technique is not viable for elements low in the periodic table (from fluorine downward) although there is research into the use of X-ray fluorescence for fluorine and boric oxide. To this end, a method has been developed for the determination of B2O3, which allows either a wet chemical or inductively coupled plasma (ICP) finish, the latter being based on methods for the pottery industry. Another wet (colorimetric) method for the determination of Hexavalent chromium has also been produced. Finally, in the area of black and nitride ceramics, a series of standards is appearing that allow their characterization using a mixture of X-ray fluorescence. X-ray diffraction, and special chemical speciation methods. 

AERO-CYANAMID (156-62-7) Combustible solid. Dust or powder forms explosive mixture with air. Contact with water, steam causes decomposition, forming acetylene gas, ammonia, and calcium hydrogen cyanamide. Violent reaction with strong oxidizers, fluorine, strong acids. Incompatible with barium peroxide, boric acid, dry hydrogen, hydrogen peroxide. Contact with all solvents tested also causes decomposition. 

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