Investigation of COD removal from tetracycline aqueous solutions with chitosan using response surface methodology

In this study, the removal of chemical oxygen demand (COD) from tetracycline (TC) aqueous solutions with chitosan was optimized and investigated using response surface methodology. For this aim, the central composite design was used to optimize the four variable factors (sorbent dosage (0.5-1.0 g), time (15-45 min), pH (3-9) and initial TC concentration (100-300 mg/L)) for the removal of COD from TC aqueous solutions by chitosan. According to the response surface methodology (RSM) analysis results, optimum conditions for maximum COD removal efficiency were determined as 298 mg/L for initial TC concentration, 15.5 min for contact time, 8.3 for pH and 0.5 g for sorbent dosage. The maximum COD removal efficiency under optimum conditions was determined as 91.3%. As a result, experiments showed that chitosan were a good adsorbent for COD removal from TC aqueous solutions. Keywords: Chitosan, Optimization, Removal, Tetracycline, COD