Kinetics of In-situ Degradation of Nerve Agent Simulants and Sarin on Carbon with and without Impregnants

  • Received : 2005.06.23
  • Accepted : 2005.09.07
  • Published : 2005.09.30

Abstract

Room temperature kinetics of degradation of nerve agent simulants and sarin, an actual nerve agent at the surface of different carbon based adsorbent materials such as active carbon grade 80 CTC, modified whetlerite containing 2.0 and 4.0 % NaOH, active carbon with 4.0 % NaOH, active carbon with 10.0 % Cu (II) ethylenediamine and active carbon with 10.0 % Cu (II) 1,1,1,5,5,5-hexafluoroacetylacetonate were studied. The used adsorbent materials were characterized for surface area and micropore volume by $N_2$ BET. For degradation studies solution of simulants of nerve agent such as dimethyl methylphosphonate (DMMP), diethyl chlorophosphate (DEClP), diethyl cyanophosphate (DECnP) and nerve agent, i.e., sarin in chloroform were prepared and used for the uniform adsorption on the adsorbent systems using their incipient volume at room temperature. Degradation kinetics was monitored by GC/FID and was found to be following pseudo first order reaction. Kinetics parameters such as rate constant and half life were calculated. Half life of degradation with modified whetlerite (MWh/NaOH) system having 4.0 % NaOH was found to be 1.5, 7.9, 1206 and 20 minutes for DECnP, DEClP, DMMP and sarin respectively. MWh/NaOH system showed maximum degradation of simulants of nerve agents and sarin to their hydrolysis products. The reaction products were characterized using NMR technique. MWh/NaOH adsorbent was also found to be active against sulphur mustard.

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