A novel chitosan-coated Fe–Cu CNS loaded with CMC–Alginate composite for adsorptive removal of ciprofloxacin from water

Indiscriminate usage of antibiotic, Ciprofloxacin (CIPRO) poses a serious environmental threat by accumulating in the water bodies. A novel clay-nanosheet supported with Fe-Cu nanocomposite was developed for CIPRO removal using an eco-friendly approach. This composite was immobilised in a biodegradable chitosan-coated Alginate-CMC matrix to form nanocomposite beads for ease of usage in the column reactors. About 90% CIPRO removal was attained through batch mode under optimal conditions (20 mg/L CIPRO; bead loading 2000 mg/L; bead weight 0.15 g; contact period 300 min; and pH - 6). Effect of various environmental factors such as salts NaCl and CaCl2 (0.05, 0.1, 0.2, 0.5 and 1 M), and micro contaminants humic acid and polyethylene (1, 2, 3, 4 and 5 M) on CIPRO adsorption by NC beads was studied. Pseudo-second order kinetics was observed by the removal process and Langmuir isotherm by the adsorption with a maximum removal capacity of 485.58 mg/g. The effects of various reaction parameters such as the flow rate (1, 2 and 3 mL/min), initial CIPRO concentration (20, 40 and 60 mg/L) and bed height (3, 5 and 7 cm) were studied in the column reactors. The residual toxicity of composite beads interacted CIPRO solution was analysed with environmentally relevant algae such as Chlorella sp. and Scenedesmus obliquus, and the studies confirmed significant reduction in their toxic effects.