Arsenic vesicants hydrolysis

For military purposes, unmodified arsenic vesicants are classified as persistent. However, agent vapors rapidly react with high humidity to lose most of their vesicant properties. Limited solubility slows the hydrolysis of liquid agents. Some hydrolysis products are highly toxic and extremely persistent (see Section 4.4.5). Evaporation rates range from near that of water down to that of light machine oil. 

Heat from a fire will increase the amount of agent vapor in the area. A significant amount of the agent could be volatilized and escape into the surrounding environment before it is consumed by the fire. Actions taken to extinguish the fire can also spread the agent. Combustion or hydrolysis of arsenic vesicants will produce volatile, toxic decomposition products (see Section 4.4.5). 

Steam is an effective method of destroying arsenic vesicants. However, care must be taken to limit the spread of the agent and to guard against production of the toxic and potentially vesicating hydrolysis products (see Section 4.4.5). 

Arsenical Vesicants are persistent agents. However, agent vapors rapidly react with high humidity to lose most of their vesicant properties. Limited solubility slows the hydrolysis of liquid agents. 

Vapors from Arsenical Vesicants have a density greater than air and tend to collect in low places. Liquids are persistent but are rapidly decomposed by water. These agents are absorbed into porous material, including painted surfaces, and these materials could continue to re-release vapor after exposure has ceased. Agent vapor is rapidly decomposed by moisture in the air. The rate of hydrolysis of liquid agents is limited by their low solubility in water. The liquid density of these agents is greater than that of water. 

Hydrolysis Arsenical Vesicants produce hydrogen chloride (HC1) and... 

It hydrolyses in acidic medium to form HC1 and nonvolatile (solid) chlorovinylarsenious oxide, which is a less potent vesicant than ED. Hydrolysis in alkaline medium, as in decontamination with alcoholic caustic or carbonate solution, produces acetylene and trisodium arsenate (Na3AS04). 

Reactivity Hydrolysis products Hydrochloric acid and chlorovinyl arsenous oxide, a vesicant. The latter is a nonvolatile solid that is not readily washed away by rains. Strong alkalies destroy these blister-forming properties. 

Properties Oily liquid having a geranium odor. Sp. gr. 1,88. B. P. 190°. A persistent, violent vesicant, highly toxic (arsenical poison). Can be used in liquid or vapor form, in other words, in shells, bombs, or as a spray. Decomposed by hydrolysis. Alcoholic sodium hydroxide spray used as means of destroying the product in the field, after first washing down with water. 

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