Environmental Management Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 16-1 Onogawa, Tsukuba, 305-8569, Japan.
Environmental Management Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 16-1 Onogawa, Tsukuba, 305-8569, Japan.
Water Res. 2019 Mar 1;150:40-46. doi: 10.1016/j.watres.2018.11.047. Epub 2018 Nov 21.
If photocatalytic water purification technologies will find practical applications, the impact of total dissolved solids in the source water on the activity of the photocatalyst must be evaluated. In this study, we evaluated the effects of SiO in water on a TiO ceramic photocatalyst; specifically, we determined the effects of SiO on the rate of photocatalytic degradation of formic acid (as a model contaminant) and on the rate of photocatalytic inactivation of Escherichia coli in an aqueous solution. Both the rate of formic acid degradation and the sterilization rate decreased with increasing SiO concentration. On the other hand, at a given SiO concentration, the activity of the photocatalyst did not decrease over the course of 120 h, and the surface structure of the photocatalyst did not change (i.e., no precipitate formed on the surface). The decreases in photocatalytic activity due to the presence of SiO could be recovered by flushing the experimental apparatus with distilled water. These results show that the reason for the lower photocatalytic activity in the presence of SiO than in its absence was due to adsorption of SiO onto the surface of the TiO photocatalyst and that SiO adsorption was an equilibrium process in water.
如果光催化水净化技术能够得到实际应用，那么必须评估原水中总溶解固体对光催化剂活性的影响。在这项研究中，我们评估了水中的 SiO 对 TiO 陶瓷光催化剂的影响；具体来说，我们确定了 SiO 对甲酸（作为一种模型污染物）光催化降解速率和水溶液中大肠杆菌光催化灭活速率的影响。甲酸的降解速率和杀菌速率均随 SiO 浓度的增加而降低。另一方面，在给定的 SiO 浓度下，光催化剂在 120 小时内的活性没有下降，并且光催化剂的表面结构没有变化（即，表面没有形成沉淀物）。用蒸馏水冲洗实验装置可恢复由于 SiO 的存在而导致的光催化活性的降低。这些结果表明，在存在 SiO 的情况下光催化活性较低的原因是 SiO 被吸附到 TiO 光催化剂的表面上，并且 SiO 的吸附是水中的一个平衡过程。
