AbstractAn engineering study was performed to evaluate the use of ultraviolet light and hydrogen peroxide to destroy caustic-neutralized VX nerve agent in the U.S. chemical agent stockpile as an alternative to incineration. Whereas caustic neutralization completely destroys VX, (3-ethyl-S-2-(diisopropylamino)ethyl methylphosphonothiolate, the reaction leaves a complex two-phase mixture containing organic phosphates and organosulfur compounds which require treatment prior to ultimate disposal. Studies performed in laboratory-scale (320-mL), bench-scale (10-L) and pilot-scale (20-L) reactors demonstrated that the principal products of the caustic neutralization-ethyl methylphosphonic acid (EMPA), methylphosphonic acid (MPA), 2-(diisopropylamino)ethyl sulfide (RSR), disulfide (RSSR) and the other mixed sulfides-could be oxidized to inorganic sulfate, phosphate, ammonia and carbon dioxide. The reaction was zero order above 1000 mg/L and pseudo first order below. To mineralize 10,000 lb of VX per day to less than 10 mg/L organic carbon would require more than 1100 lamps of 30 kW each.