响应面法研究水体中溶解性组分对双酚A光解的复合影响

在紫外光照射条件下,以双酚A(BPA)为模型化合物,采用响应面法(Response Surface Methodology,RSM)研究水环境中代表性可溶组分(腐殖酸(Humic acid,HA)、Fe3+、NO- 3 和Cl-)对BPA光解的复合影响。结果表明,HA、Fe3+是影响BPA光降解的显著因素,其次是NO- 3和Cl-。HA、NO- 3和Cl-对BPA的光解起抑制作用,而Fe3+为促进作用(P < 0.05)。这些代表性可溶性组分共存于水体中时表现出交互作用。作为显著性因素,Fe3+分别与Cl-或HA复合时抑制BPA的光解,HA-Cl-以及HA-NO- 3共存时则表现为促进作用。作为非显著性因素,NO- 3和Fe3+以及NO- 3和Cl-之间显示出拮抗作用。自由基猝灭实验证明,作为最重要的影响因素,HA对BPA光解的影响主要是通过其激发三重态进行的。利用天然水样得到的模型预测值和实验值之间显示较好的一致性,表明该模型可用于估算BPA在所用天然水样中的光解,但也有一定的局限性。

Multivariate effects of dissolved water components on Bisphenol-A photodegradation with response surface methodology

Multivariate effects of representative dissolved components (i.e., HA (Humic acid), Fe3+, NO- 3 and Cl-) on Bisphenol-A (BPA) photodegradation under simulated UV light irradiation was studied with Response Surface Methodology (RSM). Results showed that HA and Fe3+ were the significant factors affecting the photodegradation of BPA, followed by NO- 3 and Cl-. HA, NO- 3and Cl- significantly inhibited the photolysis of BPA, while Fe3+ promoted it (P < 0.05). When HA, Fe3+, NO- 3 and Cl- co-existed in the water environment, an interaction on the photolysis of BPA was established. As significant factors, the combination of Fe3+ and Cl- or HA respectively inhibited the photodegradation of BPA, while the coexistence of HA-Cl- or HA-NO- 3 showed promoting effect. As non-significant factors, there were antagonistic effects between NO- 3 and Fe3+or between NO- 3 and Cl-. Radical scavenging experiments unveiled that the most important factor HA on BPA photodegradation was mainly attributed to triplet-excited DOM. The predicted value of the model obtained from the natural water sample was in good agreement with the experimental value, indicating that the model can be used to estimate the photolysis of BPA in the natural water sample used, but it also has certain limitations.