American Method of Manufacture
The Chemical Warfare Service investigated carefully the three methods (German, French, and English) and finally adopted the Levinstein process. The following discussion is taken from a report originally made during construction, Sept., 1918.
The Levinstein reactor consisted of a jacketed and lead-lined vessel or steel tank, 8 feet 5 inches in diameter and 14 feet tall. The reactor contained 1,400 feet of lead pipe (outside diameter 2⅜ inches), made up into five coils, giving a total cooling surface of 1,200 square feet. The finished charge of such a reactor is 12 tons.
Ethylene was introduced through lead injectors, of which there were 16, each suspended from its own opening in the top and hanging so that the end of the injector tube was 12 inches from the bottom of the reactor. The nozzle of the injector was ³/₁₆ inch outside diameter and ethylene was introduced through it at 40 pounds pressure.
In starting the reaction, enough sulfur chloride was introduced into the reactor to cover the central nozzles. Ethylene was now introduced, and as the reaction proceeded sulfur chloride was added in sufficient quantities to give a high rate of reaction. Brine or cold water was introduced through the cooling coils and jacket to keep the reacting temperature at 35° C.
When the charge was completed, the ethylene was turned off so that only a small amount bubbled through the nozzles and the charge syphoned off to the settling tank. These were constructed of iron, 8 feet in diameter and 19 feet tall. They were provided with iron coils by which the liquid may be cooled down, or the sulfur, which precipitates in the bottom, melted. The tank was large enough to hold six complete charges of mustard gas and all the sulfur from these charges was allowed to accumulate before removal of the sulfur. The supernatant mustard gas was drawn off from above this sulfur to storage tanks.
Among the factors which influence the reaction are the following:
A temperature of over 60° C. in lead will decompose the product slowly when sulfur chloride is present.
The presence of iron decomposes the product rapidly at a temperature of 50° C. and probably at a considerably lower temperature.
The purity of the product is dependent upon the time of reaction. There is always a slow reaction between the mustard gas and sulfur chloride, and because of this the charge should be completed in 8 hours.