A novel La(OH)3 decorated co-graft tannin and polyethyleneimine co-coating magnetic adsorbent for effective and selective phosphate removal from natural water and real wastewater. (1st October 2022)

• Record Type: Journal Article
• Authors: Yang, Zijun; Hou, Jun; Pan, Zhengguo; Wu, Miao; Zhang, Mingzhi; Yin, Xuexue; Wu, Jun; Miao, Lingzhan; Liu, Qidi
• Is Part Of: Journal of cleaner production. Volume 369(2022)
• Publication Date: 2022-10-01
• Subjects: Phosphate -- Tannin -- Graft copolymer -- Lanthanum -- Magnetic adsorption -- XANES; 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.2022.133345
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: Our study synthesized La(OH)3 decorated co-graft tannin and polyethyleneimine (PEI) co-coating magnetic composites (La@TP@Fe3 O4 ). Dual organic modification with co-grafted tannin and PEI can significantly enhance the material's charge density, allowing La@TP@Fe3 O4 to maintain a high phosphate adsorbability at a wide pH range (3.0–11.0). La@TP@Fe3 O4 achieved a maximum theoretical phosphate adsorption capacity of 363.64 mg/g at 25 °C under pH 3.0 and was consistent with the Langmuir model, reaching adsorption equilibrium in 20 min. Phosphate adsorption was less affected by various coexisting ions with >90% of phosphate removal maintained after five cycles. La@TP@Fe3 O4 could be quickly separated by magnetic force with negligible La and Fe leakages. Besides electrostatic attraction, inner-sphere complexation and weak precipitation contributed to phosphate uptake on La@TP@Fe3 O4, as demonstrated by X-ray absorption near edge structure (XANES) analysis. Importantly, low La@TP@Fe3 O4 doses could quickly decrease phosphate concentrations in natural water and wastewater to meet regulatory requirements, thus highlighting the potential applicability of La@TP@Fe3 O4 for phosphate removal. Graphical abstract: Image 1 Highlights: La(OH)3 decorated co-graft tannin and PEI co-coating magnetic composite was prepared. La@TP@Fe3 O4 exhibited superior P adsorbability at a wide pH range of 3.0–11.0 High P adsorption capacity (363.64 mg/g) and fast adsorption kinetics were achieved. XANES spectra confirmed phosphate association with lanthanum (La–P) on La@TP@Fe3 O4 . Phosphate discharge standards were efficiently met in natural water and wastewater.