Rapid activation of basic hydrogen peroxide by borate and efficient destruction of toxic industrial chemicals (TICs) and chemical warfare agents (CWAs)

Abstract

The activation process of the B(OH)₃-activated H₂O₂ solution and its performance toward toxic industrial chemicals (TICs) and chemical warfare agents (CWAs) were investigated to find an efficient way to destroy TICs and CWAs. ¹¹B NMR analysis proved that B(OH)₃ reacted rapidly with basic H₂O₂ to produce peroxoborates ([B(OH)_(4-x)(OOH)_x]^-), and the proportional contents were closely related to the pH and temperature. ¹O₂ and ·O₂^- were generated, and their production increased exponentially with pH. TICs thioanisole and paraoxon were used as simulants of CWAs to investigate the decontamination performance and nucleophilic/oxidizing reactivity of the B(OH)₃-activated H₂O₂. Batch experiments proved that peroxoborates acted as the oxidants for the primary oxidation of the sulfide at a pH range of 8-12 and that ·O₂^- was responsible for the further oxidation of sulfoxide. Paraoxon degraded through OOH^--mediated S_N2 displacement with high stereo-selectivity, and the degradation rate increased exponentially with pH. Mustard gas, soman, and VX degraded effectively into nontoxic products in the B(OH)₃-activated H₂O₂ solution. A pH of 9-11 was recommended as the suitable acidity for developing the B(OH)₃-activated H₂O₂ solution to be a candidate for nucleophilic/oxidizing decontaminant, with advantages in rapid activation and low loss rate of reactive oxygen species.

Keywords: Chemical warfare agents; Decontamination; Hydrogen peroxide; Peroxoborates; Reactive oxygen species.