Preparation of double-doped Cu, N-nano-TiO2 photocatalyst and photocatalytic inactivation of Escherichia coli in ballast water

Abstract

With more and more international economic exchanges, ship transport becomes more and more frequent, which further increases the exchange capacity of ship ballast water in different sea areas, thus causing more and more serious marine problems of alien microbial invasion. Therefore, in this paper, on the basis of microbial inactivation of ship ballast water treated by uv irradiation, the influencing factors of its catalytic activity were explored by adding photocatalyst TiO2 into the bacterial suspension, That is to change the catalytic activity of titanium dioxide noble metal and other modified substances and doping amount. Firstly, the UV-sterilization was used as a control, and the modified photocatalyst nano-TiO2 was added. It was found that the sterilization rate increased greatly, indicating that the photocatalyst-modified nano-TiO2 has a very strong reinforcing effect on ultraviolet sterilization. Secondly, the photocatalyst itself was changed. It was found that the amount of photocatalyst nano-TiO2 had a great influence on UV sterilization. Within a certain range, the more the photocatalyst nano-TiO2 is, the better the sterilization effect is. Finally, changing the external conditions of the photocatalyst, it was found that the photocatalyst nano-TiO2 had the best activity at higher temperature (33 °C), alkaline (pH=8.5) or neutral (pH=7.5) and long-wave ultraviolet radiation.