H2O2/[CnMIm]HCO3对CEES的消毒动力学及机理

合成了4种不同烷基链长的1-烷基-3-甲基咪唑碳酸氢盐(C_nMIm]HCO₃, n=2, 4, 6, 8)离子液体(ILs), 并以H₂O₂水溶液(质量分数30%)为氧化剂, 研究了H₂O₂在C_nMIm]HCO₃离子液体、 H₂O和C₂H₅OH中对芥子气模拟剂2-氯乙基乙基硫醚(CEES)的消毒能力, 考察了离子液体烷基链长、 H₂O₂/CEES摩尔比和反应温度对消毒率的影响, 并对反应活化能和产物进行了分析. 结果表明, H₂O₂在不同溶剂中对CEES的消毒能力依次为BMIm]HCO₃>EMIm]HCO₃>HMIm]HCO₃>OMIm]HCO₃>C₂H₅OH>H₂O. 对于CEES在BMIm]HCO₃中形成的20 mg/mL的毒剂溶液, 当n(H₂O₂)∶n(CEES)=10时, H₂O₂可在30 min内消毒99.58%的CEES, 且该体系具有一定的低温(243 K)消毒能力. 该反应为一级反应, 活化能为15.59 kJ/mol, 低于单一过碳酸钠与CEES的反应活化能. 化学发光测试结果表明, 在碳酸氢根活化过氧化氢(BAP)体系中, 咪唑基离子液体可抑制亚砜被超氧阴离子(·O^-₂)过度氧化为砜.

Kinetics and Mechanism of Decontamination Reaction of CEES in H2O2/[CnMIm]HCO3†

A series of environmentally benign 1-n-alkyl-3-methylimidazolium bicarbonate ionic liquids(ILs)(C_nMIm]HCO₃, n=2, 4, 6, 8) was synthesized and hydrogen peroxide was employed in decontamination against 2-chloroethyl ethyl sulfide(CEES, a mustard agent simulant) in these ILs. The influencing factors such as ILs alkyl chain length, oxidant/CEES molar ratio and temperature were tested and the activation energy, reaction product in H₂O₂/BMIm]HCO₃ was analyzed. The results indicated that the solvents species can affect decontamination efficacy against CEES and they were in the following sequences: BMIm]HCO₃>EMIm]HCO₃>HMIm]HCO₃>OMIm]HCO₃>C₂H₅OH> H₂O. In H₂O₂/BMIm]HCO₃ system, 99.58% of the CEES was oxidized mainly to corresponding sulfoxide after 30 min at the concentration of 20 mg/mL and O/S molar ratio of 10. The apparent activation energy of CEES oxidized by H₂O₂/BMIm]HCO₃ was 15.59 kJ/mol. Moreover, the superoxide radical anion(·O^-₂) could be produced and oxidized ILs to 2-imidazolone, which inhibited the formation of corrosive sulfone. The result indicated that H₂O₂/BMIm]HCO₃ system may be a new option for decontamination against CEES.