Synthesis of N-doped TiO2 nanoparticle and its application for disinfection of a treatment plant effluent from hospital wastewater

Disinfection is one of the most important stages of water and wastewater treatment. Today, the use of photocatalytic processes by sunlight as a sustainable way of water disinfection has been noted. The purpose of this study was to remove coliform and fecal coliform from the effluent of a hospi-tal sewage treatment plant using the solar/N-doped titanium dioxide (TiO2) process. In order to conduct the experiments, the raw samples (effluent of secondary sedimentation) were taken from the Ali Ibn Abi Talib hospital wastewater treatment plant in Zahedan City, Iran. N-doped TiO2 nanoparticles and the samples were poured into the reactor and then exposed to direct sunlight in summer. The results indicated that the photocatalytic process efficiency was enhanced by increas-ing reaction time and nanoparticles dosage. Furthermore, it was found that N-doped TiO2 nanopar-ticles and sunlight had a synergistic effect on the deactivation of coliform and fecal coliform. The number of coliforms and fecal coliforms bacteria cells decreased from 5 x 105 to 7 x 103 MPN/100 mL and 4 x 103 to 2 x 102 MPN/100 mL in the solar/N-doped TiO2 process after 150 min, respectively. It has been generally concluded that the solar/N-doped TiO2 process can effectively deactivate a wide range of real effluent microorganisms on a laboratory scale.

Automated summary

This study utilized solar/N-doped titanium dioxide (TiO2) process to remove coliform and fecal coliform from hospital sewage treatment plant effluent. The photocatalytic process efficiency was enhanced by increasing reaction time and nanoparticles dosage. After 150 minutes of solar/N-doped TiO2 treatment, the number of coliforms and fecal coliforms bacteria cells decreased significantly. Overall, the solar/N-doped TiO2 process effectively deactivated a wide range of real effluent microorganisms on a laboratory scale.