Adsorption kinetics of ciprofloxacin and ofloxacin by green-modified carbon nanotubes

• Published in: Environmental research 2023-09, Vol.233, p.116503-116503, Article 116503
• Main Authors: Oliveira, Mariana G., Spaolonzi, Marcela P., Duarte, Emanuele D.V., Costa, Heloisa P.S., da Silva, Meuris G.C., Vieira, Melissa G.A.
• Format: Article
• Language: English
• Subjects: Antibiotics; Artificial neural networks; Carbon nanotubes; Green functionalization; Multicomponent adsorption
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2023.116503

This paper investigated the uptake of CIP and OFL in single and multicomponent adsorptive systems using modified carbon nanotubes (CNTs) as adsorbent material. The characterization analyses of the pre- and post-process material by XPS, TG/DTG, FT-IR, SEM/EDS, and XRD helped in the elucidation of the mechanisms, indicating greater involvement of n-n and π -π interactions. In the kinetic studies, the simple systems with CIP and OFL were similar, both showed equilibrium time around 20/30 min and increased adsorptive capacity with increasing initial drug concentration. In the multicomponent system, different fractions of CIP and OFL were tested and the time to reach equilibrium also varied between 20 and 30 min. In general, the adsorption capacity of CIP is slightly lower than that of OFL under the conditions tested. The selectivity analysis of the system showed that the selectivity's of the two drugs are identical in equimolar fractions. The mathematical modeling of the kinetic data indicated that in monocomponent systems, the model of pseudo-second order (PSO) adequately described both CIP and OFL kinetics. Furthermore, with the implementation of Artificial Neural Networks (ANN), it was possible to obtain a more assertive prediction of the behavior of single and binary systems. [Display omitted] •Investigation of single and competitive adsorption of ciprofloxacin and ofloxacin.•Carbon nanotubes were functionalized with iron nanoparticles via the green route.•Ofloxacin showed a greater adsorption preference than ciprofloxacin.•The main adsorption mechanisms were hydrogen bonds, π-π, and n-π interactions.•Artificial neural network successfully predicted single and binary kinetic data.