Penicillin Antibiotic (Ampicillin and Cloxacillin) Degradation Using Non-thermal Pencil Plasma Jet

In the present study, the efficacy of a non-thermal pencil plasma jet (NT-PPJ) producing arc plasma in degrading antibiotic drugs in artificial wastewater is investigated. Air is used as the plasma-forming gas. The plasma is electrically characterized, and the generated plasma species and radicals are identified using optical emission spectroscopy. Subsequently, the degradation of antibiotics in solution after plasma treatment is performed using high-performance liquid chromatography with a photodiode array detector (HPLC-PDA) and change in total organic carbon and chemical oxygen demand. The results obtained from HPLC-PDA demonstrate that plasma degradation of the antibiotic solution follows first-order degradation kinetics, with rate constants of 0.158 min -1 (ampicillin) and 0.366 min -1 (cloxacillin). Additionally, the reduction in total organic carbon (86.8% (ampicillin) and 78.6% (cloxacillin)) and chemical oxygen demand (67.1% (ampicillin) and 100.0% (cloxacillin)) supports the degradation of antibiotics using NT-PPJ. Plasma exposure for 9 minutes resulted in 76.10% and 99.99% degradation in ampicillin and cloxacillin solutions, with energy efficiency of 10.94 g kWh -1 and 14.38 g kWh -1 , respectively. The changes in physicochemical properties of the antibiotic solution support the removal of antibiotics through interaction with various plasma reactive species/radicals. Toxicity analysis indicates that plasma-degraded antibiotic solutions exhibit no toxicity towards freshwater algae. These findings suggest that NT-PPJ has enormous potential as an eco-friendly alternative for the degradation of various antibiotic drugs present in wastewater.