title: Adsorption in a Fixed-Bed Column and Stability of the Antibiotic Oxytetracycline Supported on Zn(II)-[2-Methylimidazolate] Frameworks in Aqueous Media.
abstract: A metal-organic framework, Zn-[2-methylimidazolate] frameworks (ZIF-8), was used as adsorbent material to remove different concentrations of oxytetracycline (OTC) antibiotic in a fixed-bed column. The OTC was studied at concentrations of 10, 25 and 40 mg L(-1). At 40 mg L(-1), the breakthrough point was reached after approximately 10 minutes, while at 10 and 25 mg L(-1) this point was reached in about 30 minutes. The highest removal rate of 60% for the 10 mg L(-1) concentration was reached after 200 minutes. The highest adsorption capacity (28.3 mg g(-1)) was attained for 25 mg L(-1) of OTC. After the adsorption process, a band shift was observed in the UV-Vis spectrum of the eluate. Additional studies were carried out to determine the cause of this band shift, involving a mass spectrometry (MS) analysis of the supernatant liquid during the process. This investigation revealed that the main route of adsorption consisted of the coordination of OTC with the metallic zinc centers of ZIF-8. The materials were characterized by thermal analysis (TA), scanning electron microscopy (SEM), powder X-ray diffraction (XRD), and infrared spectroscopy (IR) before and after adsorption, confirming the presence of OTC in the ZIF-8 and the latter's structural stability after the adsorption process.
authors.affiliation: Departamento de Química Fundamental, Universidade Federal de Pernambuco, Recife, Pernambuco, Brasil.
authors.forename: Janine
authors.initials: J
authors.lastname: dos Santos Ferreira da Silva
authors.affiliation: Departamento de Química Fundamental, Universidade Federal de Pernambuco, Recife, Pernambuco, Brasil.
authors.forename: Daniel
authors.initials: D
authors.lastname: López Malo
authors.affiliation: Instituto de Química, Universidade Estadual de Campinas, Campinas, São Paulo, Brasil.
authors.forename: Giovana
authors.initials: G
authors.lastname: Anceski Bataglion
authors.affiliation: Instituto de Química, Universidade Estadual de Campinas, Campinas, São Paulo, Brasil.
authors.forename: Marcos
authors.initials: M
authors.lastname: Nogueira Eberlin
authors.affiliation: Instituto de Química, Universidade Federal Fluminense, Nitéroi, Rio de Janeiro, Brasil.
authors.forename: Célia
authors.initials: C
authors.lastname: Machado Ronconi
authors.affiliation: Departamento de Química Fundamental, Universidade Federal de Pernambuco, Recife, Pernambuco, Brasil.
authors.forename: Severino
authors.initials: S
authors.lastname: Alves Júnior
authors.affiliation: Departamento de Química Fundamental, Universidade Federal de Pernambuco, Recife, Pernambuco, Brasil.
authors.forename: Gilberto Fernandes
authors.initials: GF
authors.lastname: de Sá
mesh_terms: D000327:Adsorption; D000900:Anti-Bacterial Agents / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D010118:Oxytetracycline / Q000737:chemistry*; D017967:Zinc Compounds / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D009942:Organometallic Compounds; D017967:Zinc Compounds; D010118:Oxytetracycline