Degradation of the Blister Agent BIS(2-Chloroethyl) Sulfide and Simulant 2-Chloroethyl Phenyl Sulfide on Concrete

The degradation of the Chemical Warfare Agent sulfur mustard, bis(2-chloroethyl) sulfide, and the half-mustard simulant, 2- chloroethyl phenyl sulfide was studied on ambient and moist concrete using 13C solid-state magic-angle-spinning nuclear magnetic resonance (SSMAS NMR). Two samples of concrete made by the same formulation, but differing in age and surface alkalinity, were used. The 2-chloroethyl phenyl sulfide hydrolyzed to form the 2-hydroxyethyl phenyl sulfide, which then formed the ether on all of the concrete samples. The sulfur mustard formed minor amounts of vinyl species on the newer, more alkaline concrete samples. The sulfur mustard eventually degraded to thiodiglycol and 1,4-oxathiane via the intermediate sulfonium ions H-2TG and O(CH2CH2)2S(+)CH2CH2OH on all of the concrete samples.