Phosgene cylinders

The condensation of dimethylaniline with phosgene yields, besides the p,p product, considerable quantites of the o,o and o,p compounds. The phosgene necessary for the reaction is taken from a phosgene cylinder, 3 and a small excess of dimethylaniline is used in order to be sure that all of the hydrogen chloride formed is taken up. 

Specifications for phosgene cylinders have been described [1318] and should be constructed according to regulatory standards, such as British Standard 5405 [277a]. 

Leaking phosgene gas can be destroyed by spraying the contaminated zone with large volumes of water. Although the reaction is slow, the excess of water helps to suppress dispersion [1318]. Water should not be sprayed directly onto phosgene cylinders, however, since this may increase the size of the leak as a result of the formation of corrosive HCI [1318,1486]. 

In particular, it should be noted that a phosgene sample containing only 0.1% of carbon dioxide, as measured in the liquid phase, would produce a vapour containing more that 11% CO 2, owing to the higher volatility of COj relative to COClj- This COj, and other very volatile contaminants, can be removed by distillation or by simple "bleeding" of the phosgene cylinder. 

CAS-No [75-44-5] carbonic dichloride carbon oxychloride carbonyl chloride chloroformyl chloride PHOSGENE (cylinder) COCIj... 

This incident occmred on January 23, 2010, about 2 00 a.m. at a DuPont facility in Belle, WV. The hose failttre occrrned as the operator was observing 1 ton phosgene cylinders in the phosgene shed. He anticipated he would need to switch supply cylinders soon. DuPont and the CSB estimated that about 2 poimds of phosgene escaped to the atmosphere from the hose failrtre [5]. 

Containers of phosgene solutions should be stored in secondary containers, and phosgene cylinders should be stored in a cool, well-ventilated area separate from incompatible materials. 

All the precautions necessary for the safe handling, shipping and storage of any compressed gas cylinder must be observed with phosgene cylinders. 

Pressure relief devices are prohibited for use on phosgene cylinders. 

Warming Cylinders to Help Remove Contents. Phosgene cylinders may be heated by warm air or warm water to facilitate removal of their contents. Never use steamy boiling watery or direct flame to remove contents. Never under any circumstances allow the outside of a cylinder to reach temperatures above 125°F (51.7 C). 

The standard valve outlet connection in the United States and Canada for phosgene cylinders is Connection CGA 660. The limited standard connection is Connection CGA 160. [8]... 

Phosgene was used tactically as a delayed or immediate action casualty gas. It was first employed by the Germans in WWI (Dec, 1915) in cylinders under the name D-Stoff. The French iater (1916) employed phosgene as an artillery shell filler (Collingite). During the remainder of the war it was the Allies principal war gas, used also in trench mortars, bombs, and projector drums (Ref 2)... 

Phosgene from a commercial cylinder was used (Matheson Company or Ohio Chemical Company). For the preparation of a solution of phosgene in toluene see Organic Syntheses ... 

The ester is made by adding benzyl alcohol slowly to a preformed solution of phosgene in toluene at 12-16°C, toluene solvent finally being distilled off under vacuum. When discoloured phosgene was used (probably containing iron salts from corrosion of the cylinder), a violent explosion occurred during the distillation phase, presumably involving iron-catalysed decomposition of the chloroformate ester. 

White Star (British WWI Cylinder Gas) Phosgene (50%) and Chlorine (50%) Mixture ... 

Is each receipt of material checked Yes. The supplier once sent a cylinder of phosgene. Since then, a test is performed by the maintenance staff. In addition, the fusible plugs are inspected for evidence of leakage, before a cylinder is hooked up. 

Describe an informal safety review process for using a cylinder of phosgene to charge gaseous phosgene to a reactor. Review up to the reactor only. 

Phosgene is a highly toxic gas. All safety precautions must he followed during its preparation and handling. It is stored and shipped in leak-free steel cylinders in the complete absence of any water (or moisture). 

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. 

Uses Was the first toxic gas used in World War I. German chlorine attack near Ypres, April 2, 1915. Later replaced by more effective gases. May be used in cylinders and shells in mixture with phosgene or chlorpicrin. 

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