六氯苯在水相、冰相和有机相中的光化学转化

以低压汞灯为光源研究了六氯苯(HCB)在水相、 冰相和有机溶剂中光转化的动力学过程, 分析了反应产物, 探讨了反应机理, 考察了H₂O₂, NO₂^-, Fe²⁺对水相/冰相中HCB光转化的影响. 结果表明, 在低压汞灯照射下, HCB在3个体系中的光转化速率大小为有机相>水相>冰相; H₂O₂ 促进水相中HCB的光转化而抑制冰相中HCB的光转化; NO₂^-对HCB在水相/冰相中的光化学转化均起抑制作用; Fe²⁺对水相中HCB的光转化有促进作用, 而对其在冰相中的光转化无影响; 六氯苯在3个体系中光转化的机理均为逐级脱氯过程.

Photoconversion of Hexachlorobenzene in Water,Ice and Organic Phase

The photoconversion kinetics of hexachlorobenzene(HCB) was studied under UV irradiation by using low-pressure mercury lamp as light source. The photoproducts were analyzed and on this basis the photoconversion mechanism was proposed. Also, the effects of H₂O₂, NO₂^-, Fe²⁺ on the photoconversion in water/ice were investigated, respectively. The results show that the photoconversion rates of HCB in the three systems under the irradiation changed as follows: organic phase>water>ice; H₂O₂ promotes the photoconversion of HCB in water but inhibits it in ice; NO₂^- has inhibition effect on the photoconversion of HCB both in water and in ice; Fe²⁺ promotes the photoconversion of HCB in water but has no effect in ice; the photoconversion mechanism of HCB is a step-by-step dechlorination process.