Facile Hydrolysis-Based Chemical Destruction of the Warfare Agents VX, GB, and HD by Alumina-Supported Fluoride Reagents

A facile solvent-free hydrolysis (chemical destruction) of the warfare agents VX (O-ethyl S-2-(diisopropylamino)ethyl methylphosphonothioate), GB (O-isopropyl methylphosphonofluoridate or sarin), and HD (2,2'-dichloroethyl Sulfide or Sulfur mustard) upon reaction with various solid-supported fluoride reagents is described. These solid reagents include different alumina-based powders such as KF/Al2O3. AgF/KF/Al2O3, and KF/Al2O3 enriched by so-called coordinatively unsaturated fluoride ions (termed by us as ECUF-KF/Al2O3). When adsorbed on these sorbents, the nerve agent VX quickly hydrolyzed (t(1/2) range between 0.1-6.3 h) to the corresponding nontoxic phosphonic acid EMPA as a major product (> 90%) and to the relatively toxic desethyl-VX (< 10%). The latter byproduct was further hydrolyzed to the nontoxic MPA product (t(1/2) range between 2.2-161 h). The reaction rates and the product distribution Were found to be strongly dependent on tile nature of the fluoride ions in the KF/Al2O3 matrix and on its Water content. All variations of the alumina-supported fluoride reagents Studied caused in immediate hydrolysis of the highly toxic GB (t(1/2) < 10 min) to form the corresponding nontoxic phosphonic acid IMPA. A preliminary stud), of the detoxification of HD on these catalyst Supports showed the formation of the nontoxic 1,4-thioxane as a major product together with minor amounts of TDG and vinylic compounds within a few days. The mechanisms and the efficiency of these processes were successful]), studied by solid-state P-31, C-13, and F-19 MAS NMR.