Boron trifluoride disposal

The alternate process, the vapor phase method, is carried out at higher pressures (450 psi) and temperatures (750—800°F), and hence, the vapor phase. Producers have been using a boron trifluoride catalyst but any trace water corrodes it unmercifully. Most have now switched to a crystalline aluminosilicate zeolyte catalyst, a more expensive but hardier catalyst. The newer catalyst is also noncorrosive and nonhazardous, cheaper to handle, and produces no waste streams to dispose of... 

Some boron trifluoride is evolved during the first part of the refluxing it may be disposed of by absorption in water in a gas trap [cf. Org. Syntheses, Coll. Vol. 2, 3 (1943)]. 

Method A 50 /jl (ca 250 ng) of the stock solution or of the purified extract is transferred into a reaction tube. One ml of boron trifluoride is added to the methanol, the cap is closed, and the tube is kept on a block heater (80°C) for 10 min. Two ml of water and 2 ml of -hexane are added. After thorough mixing, the layers are left to separate. Using disposable glass Pasteur pipettes, the upper layer is transferred to a clean, small vial. The extraction is repeated another two times with 2-ml portions of n-hexane. The hexane extracts are taken to dryness with a nitrogen stream, and the residue is dissolved in 1 -2 ml of injection solvent. Ochratoxin A is confirmed by the presence of an OA-methyl ester peak at delayed retention time and the disappearance of the OA peak (62). 

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. 

Solutions of boron trifluoride should be labeled and disposed of according to your institution s disposal guidelines. For more information on disposal procedures, see Chapter 7 of this volume. 

Tosylhydrazones such as (149), containing a suitably disposed olefinic group, cyclize to bicyclic azo-compounds [e.g. (150)] on treatment with boron trifluoride etherate. The allyl silanes (151) and (152) each undergo a highly stereoselective Prins-type reaction on treatment with trifluoroacetic acid, whereas other acid catalysts give mixtures. ... 

Disposal of boron trifluoride may be accomplished by slowly discharging the gas into a countercurrent flow caustic scrubber or other suitable vessel containing approximately 15-35 percent potassium hydroxide or other caustic solution. The system must contain a vacuum break, reverse flow trap, or check valve to prevent caustic solution from drawing back into the cylinder. 

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