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5032334 
Technical Report 
Sulfur Mustard Degradation on Ambient and Moist Concrete 
Brevett, CA; Sumpter, KB 
2008 
GRA and I 
e 0 
The reactivity, rate, and products for sulfur mustard were measured on ambient and moist concrete using C13 solid-state magic-angle-spinning nuclear magnetic resonance (SSMAS NMR). Three samples of concrete made by the same formulation, but differing in age and alkalinity, were used. A portion of sulfur mustard directly formed 8 to 31% vinyl moieties on the newer, more alkaline concrete sample. The balance of the sulfur mustard degraded to thiodiglycol and 1,4-oxathiane via the intermediate sulfonium ions CH-TG, H-TG, H-2TG, and O(CH2CH2)2S(+)CH2CH2OH on all of the concrete samples. The degradation of sulfur mustard occurred more quickly at elevated temperatures and with added water; half-lives on ambient substrates at 22 deg C ranged from 3.5 to 54 weeks on ambient concrete, with no reaction on ambient limestone. On moistened substrates the degradation half-lives at 22 deg C ranged from 75 to 350 hr. The Arrhenius activation energies were 47 kJ/mol on ambient concrete and 86 kJ/mol on moist concrete. The toxic sulfonium ions, which were the first product of the degradation, persisted for months to years on concrete at 22 deg C and weeks to months on concrete at 35 deg C.