Decomposition of adsorbed VX on activated carbons studied by 31P MAS NMR.
The fate of the persistent OP nerve agent O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX) on granular activated carbons that are used for gas filtration was studied by means of 31P magic angle spinning (MAS) NMR spectroscopy. VX as vapor or liquid was adsorbed on carbon granules, and MAS NMR spectra were recorded periodically. The results show that at least 90% of the adsorbed VX decomposes within 20 days or less to the nontoxic ethyl methylphosphonic acid (EMPA) and bis(S-2-diisopropylaminoethane) {(DES)2}. Decomposition occurred irrespective of the phase from which VX was loaded, the presence of metal impregnation on the carbon surface, and the water content of the carbon. Theoretical and practical aspects of the degradation are discussed.
Columbus
Ishay
I
Departments of Organic Chemistry and Physical Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness Ziona 74100, Israel.
Waysbort
Daniel
D
Shmueli
Liora
L
Nir
Ido
I
Kaplan
Doron
D
D000327:Adsorption; D002244:Carbon / Q000737:chemistry*; D002619:Chemical Warfare Agents / Q000032:analysis / Q000737:chemistry*; D003666:Decontamination / Q000379:methods; D006813:Humidity; D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation / Q000379:methods; D009946:Organothiophosphorus Compounds / Q000032:analysis / Q000737:chemistry*; D010759:Phosphorus Isotopes / Q000032:analysis*
D002244:Carbon; D002619:Chemical Warfare Agents; D009946:Organothiophosphorus Compounds; D010759:Phosphorus Isotopes; C009680:VX-agent