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Vol. 2, No. 7
Eckert's Cartridges for Safe Phosgenations



Introduction / Applications / Phosgene and Substitutes / Instructions for Use / References
Instructions for Use

Instructions for Use (Cartridge for Production of 50 mmol Phosgene) Phosgene production begins at a temperature of 80°C, below which the gas is not produced. The reaction proceeds cleanly up to 110°C. The overall reaction time decreases with increased temperature. Using the flow graphic, you can determine the time required to melt the material, and the time of addition into the reaction vessel at several temperatures. For example, at 105°C, the solid requires 6 minutes to melt, followed by production of a steady stream of phosgene over the course of 17 minutes (a rate of addition of approximately 3mmol/min).

All manipulations should be carried out in a well-ventilated fume hood.

  1. Heat an oil bath to a constant temperature between 80 and 110°C; do not exceed 110°C!
  2. Remove the cap from the cartridge.
  3. Connect the cartridge to a reaction vessel via a gastight adapter (available in starter kit 51,978-2).
  4. Clamp the cartridge vertically to a stand, and immerse the cartridge in the oil bath as far as the contents of the cartridge (max. depth: 3 cm).
  5. Use the entire contents of the cartridge; do not stop midway! The end of the reaction can be estimated from the graphic; a white residue will remain at the bottom of the cartridge after the reaction is completed.
  6. Once phosgene production has ceased, remove the cartridge from the oil bath, and disconnect it from the reaction vessel.

Disposal of Waste

After the reaction is completed, the residue in the cartridge can be neutralized by treatment with 10mL ethanol. After 30 minutes, the ethanol solution can be disposed of with any chlorinated waste solvent, and the empty cartridge disposed of as solid waste. The phosgene-resistant adapter and tubing can be reused, if desired.

 




Rate and Duration of Phosgene Addition at Varying Temperatures for 0.05 mol Cartridge