Ghodsi Soudabeh, Esrafili Ali, Sobhi Hamid Reza, Rezaei Kalantary Roshanak, Gholami Mitra, Maleki Ramin
Department of Environmental Health Engineering, School of Public Health, Isfahan University of Medical Sciences, Isfahan, Iran.
Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran.
AMB Express. 2021 Dec 3;11(1):161. doi: 10.1186/s13568-021-01324-3.
Contamination of water with bacteria is one of the main causes of waterborne diseases. The photocatalytic method on the basis of bacterial inactivation seems to be a suitable disinfectant due to the lack of by-products formation. Herein, g-CN/FeO/Ag nanocomposite combined with UV-light irradiation was applied for the inactivation two well-known bacteria namely, E. coli and B. subtilis. The nanocomposite was prepared by a hydrothermal method, and subsequently it was characterized by XRD, FT-IR, SEM, EDX and PL analyses. The optimum conditions established for the inactivation of both bacteria were as follows: nanocomposite dosage 3 g/L and bacterial density of 10 CFU/mL. In the meantime, the efficient inactivation of E. coli and B. subtilis took 30 and 150 min, respectively. The results also revealed that inactivation rate dropped with an increase in the bacterial density. It is also pointed out that OH˚ was found out to be the main radical species involved in the inactivation process. Finally, the kinetic results indicated that the inactivation of E. coli and B. subtilis followed the Weibull model. It is concluded that CN/FeO/Ag nanocomposite along with UV-light irradiation is highly effective in inactivating E. coli and B. subtilis bacteria in the aqueous solutions.
细菌污染水是水传播疾病的主要原因之一。基于细菌灭活的光催化方法由于不产生副产物，似乎是一种合适的消毒剂。在此，将g-CN/FeO/Ag纳米复合材料与紫外光照射相结合，用于灭活两种著名的细菌，即大肠杆菌和枯草芽孢杆菌。该纳米复合材料采用水热法制备，随后通过XRD、FT-IR、SEM、EDX和PL分析对其进行表征。确定的两种细菌灭活的最佳条件如下：纳米复合材料用量3 g/L，细菌密度10 CFU/mL。同时，大肠杆菌和枯草芽孢杆菌的有效灭活分别需要30分钟和150分钟。结果还表明，灭活率随细菌密度的增加而下降。还指出，OH˚被发现是灭活过程中主要的自由基物种。最后，动力学结果表明，大肠杆菌和枯草芽孢杆菌的灭活遵循威布尔模型。得出结论，CN/FeO/Ag纳米复合材料与紫外光照射相结合在灭活水溶液中的大肠杆菌和枯草芽孢杆菌方面非常有效。
