Náfrádi Máté, Alapi Tünde, Veres Bence, Farkas Luca, Bencsik Gábor, Janáky Csaba
Department of Inorganic, Organic and Analytical Chemistry, University of Szeged, Dóm Square 7-8, H-6720 Szeged, Hungary.
Department of Physical Chemistry and Materials Science, University of Szeged, Aradi Square 1, H-6720 Szeged, Hungary.
Materials (Basel). 2023 Aug 29;16(17):5920. doi: 10.3390/ma16175920.
The persulfate-based advanced oxidation process is a promising method for degrading organic pollutants. Herein, TiO and ZnO photocatalysts were combined with the peroxydisulfate ion (PDS) to enhance the efficiency. ZnO was significantly more efficient in PDS conversion and SO generation than TiO. For ZnO, the PDS increased the transformation rate of the trimethoprim antibiotic from 1.58 × 10 M s to 6.83 × 10 M s. However, in the case of TiO, the moderated positive effect was manifested mainly in O-free suspensions. The impact of dissolved O and trimethoprim on PDS transformation was also studied. The results reflected that the interaction of O, PDS, and TRIM with the surface of the photocatalyst and their competition for photogenerated charges must be considered. The effect of radical scavengers confirmed that in addition to SO, OH plays an essential role even in O-free suspensions, and the contribution of SO to the transformation is much more significant for ZnO than for TiO. The negative impact of biologically treated domestic wastewater as a matrix was manifested, most probably because of the radical scavenging capacity of Cl and HCO. Nevertheless, in the case of ZnO, the positive effect of PDS successfully overcompensates that, due to the efficient SO generation. Reusability tests were performed in Milli-Q water and biologically treated domestic wastewater, and only a slight decrease in the reactivity of ZnO photocatalysts was observed.
基于过硫酸盐的高级氧化工艺是一种很有前景的有机污染物降解方法。在此，将TiO和ZnO光催化剂与过二硫酸根离子（PDS）相结合以提高效率。在PDS转化和硫酸根生成方面，ZnO比TiO的效率显著更高。对于ZnO，PDS使甲氧苄啶抗生素的转化速率从1.58×10⁻⁶M s⁻¹提高到6.83×10⁻⁵M s⁻¹。然而，对于TiO，适度的积极作用主要体现在无氧悬浮液中。还研究了溶解氧和甲氧苄啶对PDS转化的影响。结果表明，必须考虑氧、PDS和甲氧苄啶与光催化剂表面的相互作用以及它们对光生电荷的竞争。自由基清除剂的作用证实，除了硫酸根外，即使在无氧悬浮液中羟基也起着重要作用，并且硫酸根对转化的贡献对于ZnO比对于TiO更为显著。作为基质的经生物处理的生活污水表现出负面影响，最有可能是由于氯离子和碳酸氢根的自由基清除能力。然而，对于ZnO，由于高效的硫酸根生成，PDS的积极作用成功地弥补了这一点。在超纯水和经生物处理的生活污水中进行了可重复使用性测试，仅观察到ZnO光催化剂的反应活性略有下降。
