Selective adsorption of ofloxacin and ciprofloxacin from a binary system using lignin-based adsorbents: Quantitative analysis, adsorption mechanisms, and structure-activity relationship.
Sci Total Environ
; 765: 144427, 2021 Apr 15.
Article
en En
| MEDLINE
| ID: mdl-33418328
ABSTRACT
A series of actinia-shaped lignin-based adsorbents (LNAEs) featuring lignin (LN) as the core and grafted poly(acrylic acid) (PAA) as the tentacle were designed and fabricated. Two fluoroquinolones (FQs) with similar molecular structures, ofloxacin (OFL) and ciprofloxacin (CIP), were used as targets to study the selective adsorption performance of LNAEs associated with the structural effects of the LN-based adsorbents in FQs binary aqueous system. The adsorption of the two FQs by LNAEs complied with the competitive Langmuir isothermal model, and showed selective removal of CIP over OFL due to the additional negative charge-assisted hydrogen bond (CAHB) formed between the carboxyl group of LNAEs and the secondary amino group of CIP, in addition to the effects of electrostatic attraction and normal hydrogen bonds, according to quantitative studies and density functional theory analysis. A binary nonlinear model based on phenomenological theory was applied to study the effects of PAA branched-chain length and distribution on the selective adsorption performance of the LN-based adsorbents. Accordingly, the branched-chain distribution played a more important role and higher distribution density of branched PAA could expose more adsorption sites on LNAEs' surface and improve the adsorptive selectivity. This study offers a well understanding of the structure-activity relationship of the surface grafting-modified adsorbents in binary pollutant systems and fundamental guidance for the exploitation and design of novel and efficient adsorbents.
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Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Contaminantes Químicos del Agua
/
Ciprofloxacina
Tipo de estudio:
Qualitative_research
Idioma:
En
Año:
2021
Tipo del documento:
Article