Experimental study of oxytetracycline degradation using Fenton-like processes

This study aimed to investigate the degradation efficiency of Oxytetracycline (OTC) using different Fenton processes. Fe2+ and nZVI reagents were used as Fenton reagents. To compare the effect on OTC degradation, Fenton process (FP), photo-Fenton process (P-FP), sono-Fenton process (S-FP) and sono–photo-Fenton process (S–P-FP) were applied. In addition, degradation products formed after OTC degradation by these methods, in which Fe2+ and nZVI reagents were used separately, were detected. UV-A, UV-B and UV-C lamps were used as UV light source. S-FP and S–P-FP used ultrasound with a frequency of 40 kHz and a power of 180 watts. In the use of Fe2+ and nZVI, the OTC removal efficiency (η) was determined as 45.64% and 50.28% for FP respectively, and in P-FP was 62.75%, 66.42% for UV-A light, 67.69%, 66.96% for UV-B, and 60.40%, 69.67% for UV-C. The η values were found as 86.30%, 87.75% (for UV-A), 90.28%, 89.55% (for UV-B) and 84.48%, 93.05% (for UV-C) in S–P-FP with ultrasound added. For S-FP, the η value recorded 74.86% and 77.51% for Fe2+ and nZVI application, respectively. The degradation products detected in the OTC different oxidation method were generally the same. The degradation product to be considered here is 2-Isopropyl-5-methyl-1-heptanol. LC50 and EC50 values of this product were quite low compared to other degradation products and OTC.