Carbon tetrafluoride disposal

Disposal of nitrogen trifluoride can be accomplished by combustion with a fuel such as activated charcoal, hydrocarbons, or metals at elevated temperatures. Reactions with activated charcoal produce nitrogen and carbon tetrafluoride. Carbon bed temperatures must be maintained above 1000°F (538°C) to assure reaction and to prevent gas adsorption. Similarly, nitrogen trifluoride streams can be scrubbed by introducing the gas through a packed bed of nickel or Monel turnings maintained above 1000°F (538°C), followed by caustic scrubbing. 

Since the volatile gases include sulfur tetrafluoride and thi-onyl fluoride, which possess toxicities comparable to that of phosgene, caution must be exercised in their disposal. A suitable procedure is to condense the volatile gases in a trap cooled in a mixture of acetone and solid carbon dioxide, and then to allow this material to pass slowly through an empty polyethylene bottle, which serves as a safety trap, and into a stirred aqueous potassium hydroxide solution. 

Xenon tetrafluoride and hexafluoride are very powerful oxidizing agents also. They are particularly dangerous because they react with water, giving explosive xenon trioxide. [See Cautions under the syntheses of XeF and XeO solution. The best way to dispose of xenon tetrafluoride or hexafluoride is to rinse the vessel [e.g., a protective trap) first with carbon tetrachloride and then with plenty of water, otherwise explosions may occur.)... 

Like xenon hexafluoride or xenon tetrafluoride, krypton difluoride reacts with water, giving highly explosive hydrolysis products. The best way for disposing of krypton difluoride is to allow it to react with carbon tetrachloride (see caution note under xenon tetrafluoride procedure). 

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