盐酸羟胺和酒石酸强化Fe^2＋/Na2S2O8体系降解双酚A

Enhancement on bisphenol A(BPA) degradation in Fe^(2+)/Na_2S_2O_8 system with hydroxylamine and tartaric acid

Fe^(2+)/Na_2S_2O_8(persulfate,PS)体系中存在Fe^(2+)易发生沉淀且Fe^(3+)无法还原的问题,以典型的持久性有机污染物双酚A(bisphenol A,BPA)为研究对象,分别考察络合剂酒石酸(tartaric acid,TA)和还原剂盐酸羟胺(hydroxylamine,HA)强化Fe^(2+)/PS体系对双酚A降解过程的影响。在Fe^(2+)/TA/PS体系、Fe^(2+)/HA/PS体系及Fe^(2+)/TA/HA/PS体系中分别考察了盐酸羟胺投加量、酒石酸投加量、体系pH作用范围等因素的影响,同时对氧化作用机理加以分析。研究表明:酒石酸和盐酸羟胺均能提高双酚A在Fe^(2+)/PS体系中的去除率,且均具有最优值;络合剂酒石酸起到长期促进作用,而还原剂盐酸羟胺起到短期促进作用。探针实验表明络合剂和还原剂共同强化的体系中·OH和SO_(4·)^-仍然是主要的氧化物种。当PS投加量均为2.64 mmol·L-1时,30 min内Fe^(2+)/TA/HA/PS体系中SO_(4·)^-的生成量为11.3μmol·L-1,而Fe^(2+)/PS体系中SO_(4·)^-的生成量为1.4μmol·L-1,表明体系通过加速了自由基生成速率从而加快了双酚A的降解。研究结果表明Fe^(2+)/TA/HA/PS体系在中性条件下实现了对双酚A的强化降解,显著优于Fe^(2+)/PS体系。

In order to solve the problems that Fe^2＋ tends to precipitate and it is difficult to achieve the circulation between Fe3＋ and Fe^2＋ in Fe^2＋/Na2S2O8 （PS） system, tartaric acid （TA） as a chelating gent and hydroxylamine （HA） as a reducing agent were used in Fe^2＋/PS system to enhance the degradation of bisphenol A （BPA）, a typical persistent organic pollutant. In Fe^2＋/TA/PS system, Fe^2＋/HA/PS system and Fe^2＋/TA/HA/PS system, dosages of TA and HA, pH range test and probe test were investigated and the results are as follows： both TA and HA could improve the removal rate of BPA in Fe^2＋/PS system and had the optimum dosage. A long-term improvement occurred for chelating agent TA, while a short-term improvement occurred for reducing agent HA. Probe tests showed that ·OH and SO4·- were still main oxide species in Fe^2＋/TA/HA/PS system. At PS dosage of 2.64 mmol·L-1, Fe^2＋/TA/HA/PS system produced 11.3 μmol·L-1 SO4·- in 30 min, while Fe^2＋/PS system only produced 1.4 μmol·L-1, which indicated that the BPA degradation was enhanced by accelerating the free radical formation. The results also showed that Fe^2＋/TA/HA/PS system could enhance the BPA degradation under neutral conditions, and was remarkable superior to Fe^2＋/PS system.