Lewisite polymerized

The forward reaction is favored because lewisite oxide and polymerized lewisite oxide are insoluble. In a basic solution, the trauj-lewisite isomer is cleaved by the hydroxyl ion to give acetylene and sodium arsenite this reaction may occur even at low temperatures (Rosenblatt et al, 1975 Clark, 1989). C/5-lewisite heated to over 40° C reacts with sodium hydroxide to yield vinyl chloride, sodium arsenite, and acetylene (Rosenblatt et al, 1975). In aqueous solution, the cA-isomer imdergoes a photoconversion to the trans-isomer (Rosenblatt et ah, 1975). Epstein (1956) reported that the toxic trivalent arsenic of lewisite oxide in standing water is converted to the less toxic pentavalent arsenic. 

Lewisite will rapidly react with water to form chlorovinylarsonous acid (CVAA). CVAA will slowly convert to the arsinoxide form and polymerization reactions can also occur. Earlier studies indicated that animals (species not specified) exposed to lewisite either topically or via injection were found to have measurable levels of CVAA in the urine and throughout the digestive system (Waters and Williams, 1950). 

Once formed, lewisite oxide and polymerized lewisite oxide are relatively insoluble in water. Once dry, the oxide will probably not readily redissolve or form the acid in the environment. The degradation products (and impurities) of lewisite are listed in the Appendix, Table A2. 

Reaction of the dihydroxy compound is slower, eventually forming lewisite oxide (chlorovinyl arsenous oxide) and polymerized lewisite oxide ... 

The production of two equivalents of chloride occurs within 3 min at 20°C at 5°C, the reaction is 90% complete within 2 min, and the completion of the reaction requires several hours. The hydrolysis rate constant is reported as Imin at 20°C. Hydrolysis of 2-chlorovinyl arsine oxide is slower, resulting in lewisite oxide (chlorovinyl arsenous oxide) and polymerized lewisite oxide ... 

This method is based on the interaction of Lewisite with sulphur at high temperature, which produces a tough polymeric mass, appropriate to bury in special burial grounds. The reaction goes according to the following scheme ... 

Lewisite Interaction with Ethylene Glycol Monomethacrylic Ester and Its Subsequent Polymerization. 

During long term storage, Mustard -Lewisite mixtures undergo profound change. Tough polymeric products, which may amount to 33% of each mixture, are formed. There are substantial differenes between mixtures of different provenance. Therefore, it is very difficult to choose a method universally suitable for destruction of these chemicals. Russian research on destruction of Mustard -Lewisite mixtures has revealed two technologies of special interest. 

Sulphurization in the Presence of N-Methylpyrrolidone. Interaction of Mustard -Lewisite mixtures with sulphur at temperatures of 140-150 C is the essence of the process. A polymeric alloy, which softens at temperature 90-100 C, is produced. The resulting mass should be buried in special burial grounds. 

Polymerization with Ethylene Glycol Monomethacrylic Ester and Monoethanolamine. This interaction (equations for reactions of Lewisite with this ester and of Mustard with monoethanolamine are presented above) is carried out in presence of a hydrogen chloride acceptor. Azo-bis-isobutyronitrile is used as polymerization initiator. Duration of detoxification is 2-2.5 hours. 

The Russian chemical munitions stockpile contains appreciable amounts of mixtures of Lewisite with yperite. The mentioned polymerization processes show promise also for destruction of those agent mixtures. 

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