Comparison of activated carbons Norit RB4W and Filtrasorb 400 for the removal of vancomycin from water
摘要
Misuse of antibiotics and their presence in wastewater have led to the emergence of antibiotic resistant bacteria. Vancomycin residue in water from hospital use, is associated with the appearance and spread of vancomycin resistant bacteria, i.e. considered as a serious threat for human health. This study assessed physicochemical properties of two activated carbons and linked them to their vancomycin adsorptive performance. The influence of contact time (0–168 h), pH (3–11), adsorbent dosage (100–1000 mg), temperature (15–45 °C), and initial vancomycin concentration (5–100 μg/mL) were investigated. The equilibrium of vancomycin adsorption was reached at 120 h for both Filtrasorb 400 and Norit RB4W. The sorbents exhibited peak performance at a solution pH of 5. The highest vancomycin removal efficiency was attained with 600 mg of Filtrasorb 400 at 24 h. It achieved an almost complete removal of vancomycin from solution. 1000 mg of Norit RB4W reduced vancomycin’s concentration from 48.9 to 25.6 μg/mL (47.64%). Temperature modification showed no statistically significant effect on vancomycin concentration of Norit RB4W and control samples at 24 h. However, Filtrasorb 400 presented a notable increase in removal efficiency with increasing temperature. Moreover, removal efficiency was found to be inversely proportional to initial vancomycin concentration. Physisorption was likely to be the prevalent mechanism of vancomycin removal from aqueous samples. Filtrasorb 400 demonstrated superior performance in removing vancomycin from water as it contains wider mesopores as well as higher mesopore content and larger specific surface area, compared to Norit RB4W.