Treatment of chemical warfare agents by combined sodium percarbonate with tetraacetylethylenediamine solution

Abstract

Treatment of chemical warfare agents (CWAs) including soman (GD), mustard (HD) and VX by combined sodium percarbonate and tetraacetylethylenediamine (SPC/TAED) solution was investigated. The optimal pH value for the degradation of HD and VX were about 7.5–9.0 and 8.5–9.5, respectively. The decontamination efficiency of GD increased as the pH value increases. To obtain a decontamination percentage of >99%, the molar ratio between active oxygen and CWAs needed to be at least 3, 2, 10 for GD, HD and VX, respectively. The SPC/TAED aqueous solution was used to effectively decompose CWAs in the temperature range between 0°C and 45°C. As indicated by the products analysis using gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS) and ion chromatography (IC), the degradation of GD was revealed to be a perhydrolysis process; oxidation of C and S atoms and elimination of HCl were involved during the degradation of HD, while VX degradation process was through oxidation of C, S and N atoms and cleavage of CC, CN, CS and PS bonds. The porous and non-porous materials (e.g., concrete, alkyd paint coating, glaze floor, etc.) contaminated by CWAs could be decontaminated by the SPC/TAED aqueous solution.