Boron trifluoride cylinders

Boron trifluoride method. Fit a 1 litre three-necked flask with a gas inlet tube, a gas outlet leading to an alkali trap (compare Fig. 11,8, laori for the unabsorbed boron trifluoride), and stopper the third neck. Place 68 g. (73 ml.) of pure, anhydrous acetone (1) and 255 g. (236 ml.) of A.R. acetic anhydride in the flask and cool in a freezing mixture of ice and salt. Connect the gas inlet tube through an empty wash bottle to a cylinder of commercial boron trifluoride (2), and bubble the gas through the reaction mixture at such a rate that 250 g. is absorb in about 5 hours (2 bubbles per second). Pour the reaction mixture into a solution... 

Boron trifluoride may be purchased in cylinders from Har-shaw Chemical Company, Cleveland, Ohio. 

The addition of a gas to a reaction mixture (commonly the hydrogen halides, fluorine, chlorine, phosgene, boron trifluoride, carbon dioxide, ammonia, gaseous unsaturated hydrocarbons, ethylene oxide) requires the provision of safety precautions which may not be immediately apparent. Some of these gases may be generated in situ (e.g. diborane in hydroboration reactions), some may be commercially available in cylinders, and some may be generated by chemical or other means (e.g. carbon dioxide, ozone). An individual description of the convenient sources of these gases will be found under Section 4.2. 

The required volume of dry xylene is measured into a graduated cylinder and a portion is transferred to a reagent bottle. The appropriate amounts of liquified phenol and boron trifluoride-phenol complex are similarly measured out and quickly transferred to the same reagent bottle. After each of the additions, the cylinder is washed well with the remaining portion of the xylene... 

Boron trifluoride, BF3. Mol. wt. 67.82, b.p. —101°. Supplier Harshaw. The reagent is available in cylinders and can be bubbled into a reaction mixture. 

Boron trifluoride is available commercially in cylinders, e.g., from the Imperial Smelting Corporation Ltd., 37 Dover Street, London, W. 1, and from Matheson Company Inc., East Rutherford, N. J., U.S.A. It is advantageous to bubble the gas through 95 per cent, sulphuric acid. Boron trifluoride acetic acid complex, largely BF,.2CH,COOH, containing about 40 per cent. BF is obtainable from Imperial Smelting Corporation Ltd. 

Now, connect the gas-intel tubing through a clean and empty wash-bottle to a filled cylinder of commercial boron trifluoride and allow the gas (BFg) to bubble through the reaction mixture, at the rate of 2 bubbles per second, so that 2.5 g is absorbed in about 65-75 minutes duration. 

Boron trtfluorlde forms complexes with ether, acidic acid, phenol, etc. Forms monohydrate and/or dIhydrate with substandard water. The cfihydrate is a corrosive liquid with melting point at 6 C. TLV is maximum and must not be exceeded. Lung edema symptoms usually develop several hours later and are aggravated by ph ical exertion rest and hospitalization essential. Do not spray leaking cylinder wittt water (to avoid corrosion). The boron trifluoride dltq rate has HI no. 80 and UN no. 2851. 

Boron Trifluoride - BF3, 7637-07-2 inhalation poison, irritant, nonflammable bp = -100"C [-148"F] er = NA sp g = 2.3 ceiling PEL = 1 ppm. irritating to eyes and respiratory system. Animals have been shown to have kidney damage after high exposures. Baseline physical should stress respiratory system, eyes, and kidneys. Tests should include a chest X-ray, pulmonary function test. Cylinders with a slow leak can be allowed to leak into an efficient fume hood for disposal, or seal the cylinder and return to the vendor. Produces a thick white smoke by interaction with moisture in humid air, but otherwise insufficient data on warning properties. On EPA hst of extremely hazardous substances, 40 CFR Section 302. 

Boron trifluoride should be handled in the laboratory using the "basic prudent practices" described in Chapter 5.C, supplemented in the case of work with gaseous boron trifluoride with the procedures of Chapter 5.H. All work with boron trifluoride should be conducted in a fume hood to prevent exposure by inhalation, and splash goggles and impermeable gloves should be worn to prevent eye and skin contact. Cylinders of boron trifluoride should be stored in locations appropriate for compressed gas storage and separated from alkali metals, alkaline earth metals, and other incompatible substances. Solutions of boron trifluoride should be stored in tightly sealed containers under an inert atmosphere in secondary containers. 

In the event of accidental release of boron trifluoride gas, evacuate the area, and if the cause of the release is a leaking cylinder, remove the cylinder to a fume hood or open area if it is possible to do so safely. Positive pressure air-supplied respiratory protection and protective elothing may be necessary to deal with a leaking cylinder of boron trifluoride, and emergency response personnel should be notified. 

Cylinders containing excess boron trifluoride should be returned to the manufacturer. 

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