Comparative analysis of conventional light source and LED array combined with the catalyst for degradation of antibiotics

In this study, the LED array system (UV and visible light) was established, and the theoretical light distribution of the reactor was simulated in MATLAB. The light field of the conventional light source is more uniform than that of the LED array, and the light field uniformity of the LED array can optimize by increasing the number of LED. Various combinations of light sources and catalysts were subjected to batch experiments in laboratory-scale reactors. All experiments are consistent with the Langmuir-Hinshelwood model, where k UV-LEDs array [P25-Sulfamethazine] =0.0018 min −1 and k Blue-LEDs array [Ag3PO4-Tetracycline] =0.0077 min −1 . In comparison experiments, conventional light sources exhibited faster dynamics compared to LED array light sources, where k Mercury lamp [P25- Sulfamethazine] =0.0209 min −1 and k Xenon lamp [Ag3PO4- Tetracycline] =0.0221 min −1 . Besides, all experiments are analyzed for electric energy per order ( E EO ). Specifically, the E EO value of the xenon lamp is 121 times that of the blue- LEDs array when the tetracycline concentration is 50 mg/L. The UV–vis of the catalyst is also coupled with the emission spectrum of the light source to evaluate the figures-of-merit of the system. The figures-of-merit ratio of the mercury lamp to the UV-LEDs array is 58.4, and the figures-of-merit ratio of the xenon lamp to the blue-LEDs array is 69.8. The obtained model can be applied to different reactors. This work demonstrates that the photocatalytic system driven by the LED array is superior to the conventional light source system regarding photon utilization rate and sustainability.