Treatment of wastewater containing ciprofloxacin using the hybrid treatment approach based on acoustic cavitation

Abstract

The present work investigates the treatment of wastewater containing an antibiotic, ciprofloxacin (CIP), using acoustic cavitation (AC) coupled with other advanced oxidation processes (AOPs). For the laboratory scale degradation study, operating parameters like drug concentration, operating pH, and initial temperature were initially optimized and then used in hybrid approach of AC in combination with AOPs. At 15 m/L initial drug concentration, neutral pH of 7, and ambient temperature of 30°C, optimum CIP degradation of 13.66% was obtained within 120 min of operation. The intensification of the AC‐based approach was subsequently achieved using other oxidants like H2O2, potassium persulphate (KPS), and O3. The combination of AC with H2O2 and KPS resulted in 44.30% and 35.41% CIP degradation, respectively, while AC combined with ozone resulted in almost complete degradation of CIP within 90 min of treatment with a maximum cavitational yield of 4.761 × 10−6 mg/J. The cost estimation for the optimized treatment approaches revealed that AC combined with ozone is the best process for degradation with the least operational cost of 8.7 Rs/L (105 US $/m3). Complete degradation of CIP with AC + O3 based approach at much lower costs opens a window for implementation in the pharmaceutical industries.