Biosorbents from tomato, tangerine, and maple leaves for the removal of ciprofloxacin from aqueous media

Ciprofloxacin is a fluoroquinolone antibiotic that is effective in vitro against Gram- positive and Gram-negative microorganisms. Since the ciprofloxacin, along with other pharmaceuticals, can influence the environment, the goal of this study was to examine the possibility of ciprofloxacin removal from water using biosorbents, an unconventional and cheaper subclass of adsorbents. For this purpose, the effect of ionic strength, pH, temperature, different mass of the used biosorbent, and physical- chemical characteristics of biosorbents on ciprofloxacin sorption was investigated. Biosorbents, used in this study, are the various waste products like maple leaves (ML), tangerine peel (TP), and tomato waste (TW) (seeds and peel). Sorption parameters of ciprofloxacin were determined by linear, Freundlich, and Dubinin-Radushkevich isotherms. The highest value of the sorption coefficient, Kd, shows the maple leaves, while the minimum achieves a sample of tangerine peel. These values correspond to the analysis and distribution of pore size, where the tangerine peel sample has the lowest specific surface area. The obtained results indicated the potential of investigated biosorbents to sorption of ciprofloxacin, which ultimately can contribute to environmental protection and the disposal of waste products.