Resumen de Hydroxyl radical based degradation of ciprofloxacin in aqueous solution
Murtaza Sayed, Luqman Ali Shah, Javed Ali Khan, Noor Samad Shah, Hasan M Khan, Rafaqat Ali Khan, Abdur Rahman Khan, Asad M Khan
This study reports the degradation of ciprofloxacin (CIP) by means of ionizing radiations. Kinetic studies with aqueous concentrations of 4.6, 10, 15, 17.9 mg/L reveals that degradation of CIP follows pseudo-first order kinetics and the decay constant increased with decrease in initial concentration of CIP. The removal efficiency, represented by G-value, decreased with increasing absorbed dose and increased with higher [CIP]0 concentration at a given absorbed dose. The effects of bubbling CIP solution with N2, N2O or air on CIP degradation were also studied. The influence of various radical scavengers like tert-butanol, iso-propanol, HCO3- , CO3(2-) , NO3- and NO2- as radical scavengers in N2- saturated solutions of CIP indicated that 'OH were more closely associated with the radiolytic decomposition of CIP than other radicals, such as e-aq or ·H. The pH value of aqueous media played a crucial role in the degradation of CIP. It was observed that degradation efficiency was higher under acidic condition compared to degradation in natural or alkaline media. F-, CH3COO- and HCOO- were formed as a result of CIP degradation that were analyzed by ion-chromatography.
