Aqueous norfloxacin removal by novel biochar adsorbent prepared through ethanol-combined ball milling

ABSTRACT

Ethanol combined-ball milling was used to modify corn-stover biochar. The adsorption performance and mechanisms of aqueous norfloxacin (NOR) onto the resulting biochar (C₂H₆O-BC) were evaluated. Ball-milling modulated its surface oxygen-containing functional groups and enhanced its specific surface area. The adsorption capacity of C₂H₆O-BC was 163 mg·g⁻¹, and about 72% of the equilibrium adsorption capacity could be reached within 60 min. The electrostatic interaction was not the dominant mechanism when initial pH was lower than 8.00. The antagonistic effect of Cu(II) on NOR adsorption was observed. The fixed-bed column adsorption showed its potential to remove NOR and Cu(II) spontaneously. Sequential two-stage batch reaction experiment showed that it was a fast and efficient technology to remove NOR using C₂H₆O-BC. The adsorption mechanisms were suggested as π-π interactions, H-bonding and pore-filling. In summary, ethanol-combined ball milling in this study provided an efficient adsorbent for NOR.

KEYWORDS:

• Corn-stover-based biochar
• mechanical ball milling
• batch adsorption
• fixed-bed column adsorption
• sequential two-stage batch reaction
• adsorption mechanism

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

Data will be made available on request.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/26395940.2024.2311675.

Additional information

Funding

This work was partly supported by the National Key R&D Program of China [No. 2018YFC1800600] and the National Natural Science Foundation of China [No.21677075]. Ding Z. thanks for the support of “Jiangsu 333 High Level Talent Training Project [2022-2026]”. Yang S. also thanks for the support of “Postgraduate Research & Practice Innovation Program of Jiangsu Province [KYCX23_1484]”.