Herrera Melián J A, Doña Rodríguez J M, Viera Suárez A, Tello Rendón E, Valdés do Campo C, Arana J, Pérez Peña J
Departamento de Química, Universidad de Las Palmas de Gran Canaria, Spain.
Chemosphere. 2000 Aug;41(3):323-7. doi: 10.1016/s0045-6535(99)00502-0.
In this paper we present the results of the photocatalytic disinfection of urban waste water. Two microbial groups, total coliforms and Streptococcus faecalis, have been used as indexes to test disinfection efficiencies. Different experimental parameters have been checked, such as the effect of TiO2, solar or UV-lamp light and pH. Disinfection of water samples has been achieved employing both UV-lamp and solar light in agreement with data shown by other authors. The higher disinfection rates obtained employing an UV-lamp may be explained by the stronger incident light intensity. Nevertheless no consistent differences have been found between TiO2-photocatalysis and direct solar or UV-lamp light irradiation at natural sample pH (7.8). At pH 5 the presence of TiO2 increases the relative inactivation rate compared with the absence of the catalyst. After the photocatalytic bacterial inactivation, the later bacterial reappearance was checked for total coliforms at natural pH and pH 5, with and without TiO2. Two h after the photocatalytic treatment, CFU increment was almost nill. But 24 and 48 h later an important bacterial CFU increment was observed. This CFU increment is slower after irradiation with TiO2 at pH 5 in non-air-purged samples.
在本文中，我们展示了城市废水光催化消毒的结果。使用了两个微生物组，即总大肠菌群和粪肠球菌，作为测试消毒效率的指标。检查了不同的实验参数，如二氧化钛的作用、太阳光或紫外灯光以及pH值。与其他作者的数据一致，使用紫外灯和太阳光都实现了水样的消毒。使用紫外灯获得的较高消毒率可能是由于更强的入射光强度。然而，在天然样品pH值（7.8）下，二氧化钛光催化与直接太阳光或紫外灯光照射之间未发现一致的差异。在pH值为5时，与不存在催化剂相比，二氧化钛的存在提高了相对失活率。在光催化细菌失活后，检查了在天然pH值和pH值为5时，有无二氧化钛情况下总大肠菌群的后续细菌再出现情况。光催化处理两小时后，菌落形成单位（CFU）的增加几乎为零。但在24小时和48小时后，观察到细菌CFU有重要增加。在未进行空气吹扫的样品中，在pH值为5时用二氧化钛照射后，这种CFU增加较慢。
