Optimization of Neutralization Conditions and Comparative Study of Nerve Agents and Simulants Using a Reaction Calorimeter

Studies on the safe disposal of nerve agents face limitations due to the restrictions and risks associated with their use. In this study, we optimized the neutralization conditions for nerve agents pinacolyl methylphosphonofluoridate (GD), ethyl dimethylphosphoroamidocyanate (GA), and ethyl N-2-diisopropylaminoethyl methylphosphonothiolate (VX), by conducting comparative neutralization reactions using simulants and a reaction calorimeter. The neutralization reactions of diethyl chlorophosphite (DECP), diphenyl chlorophosphite (DPCP), and butyryl chloride (BC) were compared using a reaction calorimeter. More than 2 equiv of KOH neutralized over 99% of the nerve agents. To prevent the formation of precipitates and make the process suitable for the disposal of nerve agents, the reaction was conducted at concentrations of ≤40% for GD and GA and ≤60% for VX. The neutralization enthalpy of each agent was determined based on the measured heat flow; similar heat flow patterns were observed for GD, GA, DECP, and BC.