Novel ultraporous polyimide-based hollow carbon nanofiber mat: Its polymer-blend electrospinning preparation strategy and efficient dynamic adsorption for ciprofloxacin removal

• Published in: Separation and purification technology Vol. 295; p. 121341
• Main Authors: Dou, Shuai, Ke, Xiao-Xue, Zhong, Lu-Bin, Fan, Jia-Jun, Paul Chen, J., Zheng, Yu-Ming
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.08.2022
• Subjects: Carbon nanofiber; Ciprofloxacin; Column adsorption; Hollow core; Polymer-blend electrospinning; Carbon nanofiber; Polymer-blend electrospinning; Column adsorption; Ciprofloxacin; Hollow core
• ISSN: 1383-5866; 1873-3794
• DOI: 10.1016/j.seppur.2022.121341

[Display omitted] •Ultraporous hollow carbon nanofiber mat (CNFM) was fabricated without activation.•PP-CNFM-1–1 has high specific surface area (2327 m2 g-1) & pore volume (1.26 cm3 g-1).•PP-CNFM-1–1 has high CIP static adsorption capacity (>700 mg g-1) & fast adsorption rate (<1 h).•PP-CNFM-1–1 has excellent CIP dynamic adsorption capacity (>600 mg g-1).•The pore filling effect & hydrophobic interaction play major roles in CIP adsorption. A novel ultraporous polyimide-based hollow carbon nanofiber mat (CNFM) was facilely fabricated via a polymer-blend electrospinning strategy, which consisted of a simple single-needle electrospinning of two immiscible polymer solutions (polyamide acid/polymethyl methacrylate) (PAA/PMMA) and the subsequent thermal treatment, without involvement of tedious and cost-consuming activation steps. The obtained PP-CNFM-1–1 (PAA:PMMA = 1:1, mass ratio) exhibited well-developed hollow cores along the fiber length, and possesses ultrahigh Brunauer-Emmett-Teller (BET) specific surface area (SBET) of 2327 m2 g-1 and a large total pore volume of 1.26 cm3 g-1, which were superior to many activated CNFMs. The PP-CNFM-1–1 showed high ciprofloxacin (CIP) adsorption capacity of over 700 mg g-1 due to its ultrahigh SBET and abundant pores of 1–3 nm width fitting CIP molecule. Notably, the hollow core of PP-CNFM-1–1, which is similar to molecular channel, was the reason to the excellent CIP adsorption rate and a very short adsorption equilibrium time (<1h). Adsorption mechanism study implied that the pore filling effect and the hydrophobic interaction played the major roles in the adsorption process. The fixed-bed column adsorption study indicated that the PP-CNFM-1–1 had a great application potential for low concentration CIP removal.