title: Novel magnetic beads based on sodium alginate gel crosslinked by zirconium(IV) and their effective removal for Pb²⁺ in aqueous solutions by using a batch and continuous systems.
abstract: Novel magnetic sodium alginate gel beads (Fe3O4@SA-Zr) were successfully prepared by using zirconium(IV) as crosslinking ions, and used as adsorbent for removal of Pb(2+) ions from aqueous solutions in batch and fixed-bed column systems. Fe3O4@SA-Zr was characterized by SEM, FT-IR, XRD and VSM. Fe3O4@SA-Zr had the macroporous structure, exhibited greater stability and possessed a sensitive magnetic response. More importantly, Fe3O4@SA-Zr exhibited high adsorption capacity, fast kinetics and high selectivity towards Pb(2+) ions. Experimental data was well described by Langmuir isotherm with a maximum adsorption capacity of 333.33 mg/g. FTIR and XPS indicated that the carboxyl and hydroxyl groups of SA and hydroxyl groups binding to Fe and Zr species were involved in Pb(2+) adsorption. Fixed-bed column packed with Fe3O4@SA-Zr exhibited higher removal efficiency for Pb(2+)ions. Consequently, Fe3O4@SA-Zr with excellent absorbability, stability and reusability could be used as a promising adsorbent for Pb(2+) removal in wastewaters.
authors.affiliation: State Key Laboratory of Applied Organic Chemistry, College of Resources and Environment, College of Chemistry and Chemical Engineering, Institute of Biochemical Engineering & Environmental Technology, Lanzhou University, Lanzhou 730000, China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Li
authors.forename: Yongxin
authors.initials: Y
authors.lastname: Qi
authors.forename: Yanfeng
authors.initials: Y
authors.lastname: Li
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xinghua
authors.initials: X
authors.lastname: He
authors.forename: Yonghuan
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000327:Adsorption; D000464:Alginates / Q000737:chemistry*; D005782:Gels; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007854:Lead / Q000302:isolation & purification*; D008280:Magnetics; D009994:Osmolar Concentration; D056951:Photoelectron Spectroscopy; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D015040:Zirconium / Q000737:chemistry*
chemical_list: D000464:Alginates; D005782:Gels; D006603:Hexuronic Acids; D014874:Water Pollutants, Chemical; D007854:Lead; D020723:Glucuronic Acid; D015040:Zirconium
keywords: Adsorption; Fe(3)O(4)@SA–Zr; Heavy metal; Pb(2+); Wastewater treatment