可见光照FePz(dtnCl_2)_4活化过氧化氢降解对硝基苯甲酸

Photodegradation of 4-Nitro Benzoic Acid by Hydrogen Peroxide in the Presence of FePz(dtnCl_2)_4 under Visible Irradiation

应用高效液相色谱法和固相微萃取-气相色谱质谱联用法研究了可见光(λ>420 nm)和四(1,4-二噻英-5,6-二氯)-四氮杂卟啉铁(FePz(dtnCl2)4)存在下,过氧化氢降解无可见光吸收的有机底物对硝基苯甲酸和水杨酸的行为.研究表明,在酸性和中性水溶液中,FePz(dtnCl2)4能有效地活化过氧化氢来氧化降解对硝基苯甲酸和水杨酸以使其苯环结构发生破裂,降解反应速率随pH值增大而减小.这一结果证明,FePz(dtnCl2)4为可见光激发的活化过氧化氢催化剂,该体系对有机底物的氧化降解具有良好的适应性.

The photodegradation of 4-nitro benzoic acid and salicylic acid by hydrogen peroxide in the presence of iron-tetra （5, 6-dichloro-1,4-dithin） porphyrazine （FePz （dtnCl2）4 ） under visible irradiation （λ〉420 nm） was investigated in this paper by means of high performance liquid chromatography （HPLC） and solid-phase microextraction-gas chromatography-mass spectroscopy analysis （SPME-GC-MS）. The study suggests FePz（dtnCl2）4 can efficiently activate hydrogen peroxide to oxidative degrade 4-nitro benzoic acid and salicylic acid in acidic or neutral aqueous solution thought cleavage benzoic rings, in which increasing initial pH value lowers the photodegradation rate. These results demonstrate that the photoexcitation of substrates does not play a major role and that hydrogen peroxide activated by excitated FePz （dtnCl2）4 initiates the degradation process.