title: Low-cost magnetic herbal biochar: characterization and application for antibiotic removal.
abstract: Magnetic biochar (M-BC) was derived from herbal medicine waste, Astragalus membranaceus residue, and was used as an adsorbent for ciprofloxacin removal from aqueous solutions. The M-BC was characterized by Brunauer-Emmett-Teller surface area analyses, Fourier transform infrared spectrometry, X-ray diffraction analysis, hysteresis loops, scanning electron microscopy energy-dispersive spectrometry, and X-ray photoelectron spectroscopy. The BET surface area increased from 4.40 to 203.70 m2/g after pyrolysis/magnetic modification. Batch experiments were performed at different dosages, initial concentrations, contact times, and solution pHs. Adsorption performances were evaluated using Langmuir and Freundlich isotherm models, and the results indicated that the Langmuir model appropriately described the adsorption process. The kinetic data were better fitted by a pseudo-second-order kinetic model. The maximum ciprofloxacin removal was observed at pH 6 (adsorption capacity of 68.9 ± 3.23 mg/g). Studies demonstrated that magnetically modified biochar might be an attractive, cost-effective, and easily separated adsorbent for contaminated water. Graphical abstract.
authors.affiliation: Department of Environmental Science, China Pharmaceutical University, Nanjing, 210009, China.
authors.forename: Xiangrui
authors.initials: X
authors.lastname: Kong
authors.affiliation: Department of Environmental Science, China Pharmaceutical University, Nanjing, 210009, China.
authors.forename: Yaoxuan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Environmental Science, China Pharmaceutical University, Nanjing, 210009, China.
authors.forename: Jiachang
authors.initials: J
authors.lastname: Pi
authors.affiliation: Department of Environmental Science, China Pharmaceutical University, Nanjing, 210009, China.
authors.forename: Wenhong
authors.initials: W
authors.lastname: Li
authors.affiliation: Department of Environmental Science, China Pharmaceutical University, Nanjing, 210009, China.
authors.forename: QianJiahua
authors.initials: Q
authors.lastname: Liao
authors.affiliation: Department of Environmental Science, China Pharmaceutical University, Nanjing, 210009, China. shangjingge@gmail.com.|State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China. shangjingge@gmail.com.
authors.forename: Jingge
authors.identifier: http://orcid.org/0000-0002-5282-9270
authors.initials: J
authors.lastname: Shang
mesh_terms: D000327:Adsorption; D027885:Astragalus propinquus / Q000737:chemistry; D002606:Charcoal / Q000737:chemistry*; D002939:Ciprofloxacin / Q000737:chemistry / Q000302:isolation & purification*; D007700:Kinetics; D060328:Magnetic Phenomena; D008855:Microscopy, Electron, Scanning; D056951:Photoelectron Spectroscopy; D012996:Solutions; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*; D018508:Water Purification / Q000191:economics / Q000379:methods*; D014961:X-Ray Diffraction
chemical_list: D012996:Solutions; D014874:Water Pollutants, Chemical; C540010:biochar; D002606:Charcoal; D002939:Ciprofloxacin
keywords: Adsorption; Antibiotic; Biochar; Biomass waste; Magnetic; Wastewater