Nitrogen-doped magnetic biochar made with K3[Fe(C2O4)3] to adsorb dyes: Experimental approach and density functional theory modeling. (10th January 2023)

• Record Type: Journal Article
• Authors: Zhang, Xinyu; Tran, Hai Nguyen; Liu, Yena; Yang, Chao; Zhang, Tingwei; Guo, Jiaqi; Zhu, Wenyuan; Ahmad, Mehraj; Xiao, Huining; Song, Junlong
• Is Part Of: Journal of cleaner production. Volume 383(2023)
• Publication Date: 2023-01-10
• Subjects: Magnetic biochar -- Chemical activation -- Dye -- Adsorption mechanism -- Density functional theory (DFT) calculation; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2022.135527
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: Magnetic biochar displays promising applications in dye wastewater treatment since it can be effectively separated by magnetism. However, the preparation of magnetic biochar with a large specific surface area is complicated and the effects of ferrous and/or ferric ions on dye adsorption are not clear enough. Herein, a facile one-pot approach of magnetic self-nitrogen-doped biochar fabrication was developed, using K3 [Fe(C2 O4 )3 ] as an activator and iron supplier. Magnetic self-nitrogen-doped biochar could be easily separated with a magnet. Magnetic self-nitrogen-doped biochar had a large specific surface area (1034 m 2 /g) and excellent adsorption capacities for Congo red (1360 mg/g) and Rhodamine B (320 mg/g). From thermodynamics studies, Congo red adsorption on magnetic self-nitrogen-doped biochar is better than Rhodamine B. Based on the larger adsorption energies, magnetic self-nitrogen-doped biochar has a relatively stronger binding ability for Congo red than Rhodamine B, and the ferrous ions loaded on biochar surface are more beneficial for dye adsorption than ferric ones. Graphical abstract: Image 1 Highlights: K3 [Fe(C2 O4 )3 ] worked as an activator and iron loading agent in biochar modification. High iron content up to 38.7 wt% could be loaded in biochar. Adsorption capacities reached 320–1360 mg/g for Rhodamine B and Congo Red Presence of iron on carbon surface affected the interactions with dyes. Ferrous iron was more effective than ferric in dye removal.