Mustard oxidative decontamination

Both hydrolysis and oxidation can be speeded up by catalysts. Wagner-Jauregg et al. (1955) and Gustafson and co-workers (1959,1962,1963) have investigated the use of copper as a catalyst for the hydrolysis of nerve agents and sulphur mustard. Iron has been studied as a catalyst of oxidative decontamination the reader is referred to Yang et al (1992) for detailed comments. 

The oxidative decontamination process for mustard, a CWA threat of major concern, targeted by us and others, is selective sulfoxidation, eq 1, because the sulfoxide has been known for decades to be far less toxic than mustard itself (2, 3). 

Gonzaga, R, Perez, E., Rico-Lattes, L, and Lattes, A. 2001. New microemulsions for oxidative decontamination of mustard gas analogues and polymer-thickened half-mustard. New J Chem, 25, 151-155. 

One such decontaminant is supertropical bleach (STB). STB is a mixture of chlorinated lime and calcium oxide containing about 30% available chlorine. It can be used either as a dry mix or as a slurry to decontaminate some equipment surfaces and terrain. The dry mix is prepared with two parts bleach to three parts earth by volume. A slurry typically consists of 40 parts STB to 60 parts by weight of water. This material is then sprayed or swabbed on the contaminated surface (see Bleaching agents). STB is an effective decontaminant for mustard, lewisite, and VX. It is less effective against nerve agents other than VX. 

Under environmental conditions, CWAs (vesicant agents, sulfur mustard (H, HD and HT) and lewisite (L) nerve agents, GA, GB, GD and VX) can undergo multiple-degradation processes such as hydrolysis, oxidation, dehydration and photolysis. These baseline degradation reactions can vary in rate and completeness, depending upon reaction temperature and pH, as well as the presence of free radicals and catalysts. Knowledge of these baseline reaction parameters has formed the basis for many modern decontamination procedures. 

The contractor, Western Research Partnerships, Calgary, AB (Chem-Security Ltd. and Western Research Ltd. Both companies are now a part of BOVAR Inc., Calgary) supplied and operated a transportable incinerator which was used to thermally treat the scrap waste and emptied, decontaminated ordnance items and to bum mustard. Lewisite was chemically destroyed by peroxide oxidation in a transportable facility and the arsenic salt by-products were stabilized in concrete for on-site disposal in a marked landfill. 

Sulfur mustards are oxidized with strong oxidants and are hydrolyzed with alkali, generally producing reaction products that are less toxic. Reactions with chlorine or chlorinating agents such as NaOCl or Ca(OCl)2 yield nontoxic products. This reaction is suitable to inactivate and decontaminate sulfur mustards. The physical, chemical, and toxic properties of mustard gas and a few selective compounds of this class are outline below. 

Three types of chemical mechanisms have been used for decontamination water/soap wash oxidation and acid/base hydrolysis.9 Mustard (HD) and the persistent nerve agent VX contain sulfur molecules that are readily subject to oxidation reactions. VX and the other nerve agents (tabun [GA], sarin [GB], soman [GD], and GF) contain phosphorus groups that can be hydrolyzed. Therefore, most chemical decontaminants are designed to oxidize mustard and VX and to hydrolyze nerve agents (VX and the G series).1 Water and Water/Soap Wash... 

The M258A1 Skin Decontamination Kit is designed to remove and neutralize liquid chemical agents on the skin. The kit consists of three number 1 liquid packets and three number 2 liquid packets (Figure 16-36). The number 1 packet will neutralize G-series nerve agents by hydrolysis, and the number 2 packet will neutralize VX and mustard agents by oxidation.41... 

Key words Amino acids. Catalytic oxidation under ambient conditions, 2-chloroethyl ethyl sulfide, Co-catalysis by copper. Decontamination, Effect of ligands, Gold complexes. Mustard gas, Perfluorinated solvents. Solvent effect. Sulfoxide, Thioether... 

Prasad, G.K., Mahato, T.H., Singh, B., et al., 2007a. Decontamination of sulfur mustard on manganese oxide nanostructures. AIChE J. 53 (6), 1562-1567. 

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