title: Optimized removal of antibiotic drugs from aqueous solutions using single, double and multi-walled carbon nanotubes.
abstract: In this study, experiments were carried out to investigate the use of as-synthesized single-walled (SWCNT), double-walled (DWCNT) and multi-walled carbon nanotubes (MWCNT) agglomerates for the removal of two antibiotics, Oxytetracycline (OXY) and Ciprofloxacin (CIP) from aqueous solution. The variations of key operating parameters on the removal process were assessed in order to find out the optimum conditions. It includes exposure time, solution pH, temperature, ultrasound assistance and desorption assays. The experimental results revealed that a moderate increase in adsorption was registered between pH 3 and 7 for both antibiotics. The application of ultrasound helped enhancing the removal capacities of OXY for all tested CNTs. For the case of MWCNTs, 1h of ultrasonication increased the adsorption capacity by 44.6%. As for CIP, the ultrasonic treatment did not enhance the overall adsorption, especially for the case of DWCNTS. The Brouers-Sotolongo equation was the best fitting isotherm model. The highest removal capacities were registered using SWCNTS for both antibiotics (724 mg/g for CIP and 554 mg/g for OXY). In addition, ethanol was the solvent that induced the highest desorption percent for the case of CIP (52% for MWCNTs). However, the desorption of OXY was negligible for all solvents (maximum 3.3% for DWCNTs using ethanol).
authors.affiliation: Laboratory of Green Chemistry, School of Engineering Science, Lappeenranta University of Technology, Sammonkatu 12, 50130, Mikkeli, Finland. Electronic address: chaker.necibi@lut.fi.
authors.forename: Mohamed Chaker
authors.initials: MC
authors.lastname: Ncibi
authors.affiliation: Laboratory of Green Chemistry, School of Engineering Science, Lappeenranta University of Technology, Sammonkatu 12, 50130, Mikkeli, Finland.
authors.forename: Mika
authors.initials: M
authors.lastname: Sillanpää
mesh_terms: D000327:Adsorption; D000900:Anti-Bacterial Agents / Q000302:isolation & purification*; D002939:Ciprofloxacin / Q000302:isolation & purification; D004350:Drug Residues / Q000302:isolation & purification; D006863:Hydrogen-Ion Concentration; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010118:Oxytetracycline / Q000302:isolation & purification; D016062:Porosity; D012996:Solutions; D012997:Solvents; D013816:Thermodynamics; D014465:Ultrasonics; D014867:Water; D014874:Water Pollutants, Chemical / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D037742:Nanotubes, Carbon; D012996:Solutions; D012997:Solvents; D014874:Water Pollutants, Chemical; D014867:Water; D002939:Ciprofloxacin; D010118:Oxytetracycline
keywords: Antibiotics; Carbon nanotubes; Desorption; Optimization; Removal