Rapid removal of Cr(VI) from aqueous solution by novel sepiolite/Fe₃O₄/nZVI nanocomposite: Material characterizations, enhanced performance in Cr(VI) removal and mechanism

Abstract

The novel magnetic sepiolite/Fe₃O₄/zero-valent iron (nZVI) nanocomposite (nZVI@SepH-Mag) was prepared and used to achieve the removal of Cr(VI) in this work. The nZVI@SepH-Mag composites were characterized by XRD, FTIR, BET, SEM and TEM. The characterization results indicated that the structure of the composite consisted of small nanoscale nZVI and magnetite (Mag) particles uniformly anchoring on the surface of acid-activated sepiolite (SepH). Batch experiments were used to analyze the effects of main factors on Cr(VI) removal. A 100% removal efficiency in 60 min and enhanced reaction ratio were reached by the composite comparing other existing materials. The kinetic of the adsorption and possible Cr(VI) removal mechanism of the hybrids were also evaluated and proposed. Based on the removal products identified by Raman, XRD and XPS, a reduction mechanism was proposed. The results indicated that the SepH and Mag can inhibit the agglomeration and enhance the dispersibility of nZVI, and Mag and nZVI displayed good synergetic effects.

An erratum to this article is available online at https://doi.org/10.1007/s11771-025-6033-0.

Keywords

magnetic adsorbent materials / nanocomposites / Cr(VI) / adsorption / adsorption mechanism

References

[1] YangT, HuX-y, WangJ-t, et al.. Interfacial coupling effects in g-C₃N₄/In_xSb_2−xS₃ heterojunction for enhanced photocatalytic activity under visible light. Journal of Central South University, 2022, 29(5): 1447-1462[J]

[2] LouJ-q, XuH, JinH, et al.. Interaction between Cr(VI) and Tubificidae in sludge reduction system: Effect, reduction, and redistribution of Cr(VI). Environmental Science and Pollution Research International, 2023, 30(41): 94803-94813[J]

[3] ZhangX-l, LiuY-f, LiC-j. Influence of Cr(VI) concentration on Cr(VI) reduction and electricity production in microbial fuel cell. Environmental Science and Pollution Research International, 2021, 28(38): 54170-54176[J]

[4] LiangC-w, FuF-l, TangB. Mn-incorporated ferrihydrite for Cr(VI) immobilization: Adsorption behavior and the fate of Cr(VI) during aging. Journal of Hazardous Materials, 2021, 417126073[J]

[5] WangY, WangC-y, ChengC, et al.. Chromium removal at neutral pHs via electrochemical Cr(VI) reduction and subsequent Cr(III) adsorption with MoS₂ nanoflowers-modified graphite felt. Journal of Hazardous Materials, 2023, 455131582[J]

[6] LiangR-f, HanL-y, WangY-z, et al.. Novel Ti-coordination polydopamine nanocomposite with a combination of adsorption, reduction, and ion exchange for rapid Cr(VI) removal. Industrial & Engineering Chemistry Research, 2022, 61(27): 9717-9724[J]

[7] LuW-l, DuanC, ZhangY-l, et al.. Cellulose-based electrospun nanofiber membrane with core-sheath structure and robust photocatalytic activity for simultaneous and efficient oil emulsions separation, dye degradation and Cr(VI) reduction. Carbohydrate Polymers, 2021, 258117676[J]

[8] XiaX, WuS-j, ZhouZ-j, et al.. Microbial Cd(II) and Cr(VI) resistance mechanisms and application in bioremediation. Journal of Hazardous Materials, 2021, 401123685[J]

[9] LiS-j, CaiM-j, LiuY-p, et al.. Constructing Cd_0.5Zn_0.5S/Bi₂WO₆ S-scheme heterojunction for boosted photocatalytic antibiotic oxidation and Cr(VI) reduction. Advanced Powder Materials, 2023, 21100073[J]

[10] LiS-j, YouC-j, RongK, et al.. Chemically bonded Mn_0.5Cd_0.5S/BiOBr S-scheme photocatalyst with rich oxygen vacancies for improved photocatalytic decontamination performance. Advanced Powder Materials, 2024, 33100183[J]

[11] WangC-c, YouC-j, RongK, et al.. An S-scheme MIL-101(Fe)-on-BiOCl heterostructure with oxygen vacancies for boosting photocatalytic removal of Cr(VI). Acta Physico-Chimica Sinica, 2024, 4072307045[J]

[12] GuT-y, NiuW-j, HuoL-l, et al.. Molasses-based in situ bio-sequestration of Cr(VI) in groundwater under flow condition. Environmental Pollution, 2024, 344123337[J]

[13] YangB-w, DaiJ-w, ZhaoY, et al.. Synergy effect between tetracycline and Cr(VI) on combined pollution systems driving biochar-templated Fe₃O₄@SiO₂/TiO₂/g-C₃N₄ composites for enhanced removal of pollutants. Biochar, 2023, 511[J]

[14] LiH-y, QianL-b, LiangC, et al.. Enhanced Cr(VI) reduction by zero-valent iron and ferroferric oxide wet ball milling: Synergy of electron storage and electron transfer. Chemical Engineering Journal, 2023, 457141254[J]

[15] AmbikaS, DevasenaM, NambiI M. Single-step removal of Hexavalent chromium and phenol using meso zerovalent iron. Chemosphere, 2020, 248125912[J]

[16] LiJ, FanM-j, LiM, et al.. Cr(VI) removal from groundwater using double surfactant-modified nanoscale zero-valent iron (nZVI): Effects of materials in different status. Science of the Total Environment, 2020, 717137112[J]

[17] ZhangP, MengX-y, FanM-y, et al.. Customized design of nZVI supported on an N-doped reduced graphene oxide aerogel for microwave-assisted superefficient degradation of imidacloprid in wastewater. Applied Catalysis B: Environmental, 2024, 340123258[J]

[18] DengQ, WangX-t, FuY, et al.. Preparation and properties of high vinyl polybutadiene/sepiolite nanocomposites using a sepiolite immobilized Mo-based catalyst. Journal of Applied Polymer Science, 2023, 14039e54468[J]

[19] LiuJ-q, XinZ-x. Effect of sepiolite on properties of silicone rubber/melamine/starch/sepiolite flame retardant composites. Journal of Applied Polymer Science, 2023, 1409e53538[J]

[20] ZhangS, ZhangD-s, FengG-r, et al.. Modelling method of heterogeneous rock mass and DEM investigation of seepage characteristics. Geomechanics and Geophysics for Geo-Energy and Geo-Resources, 2024, 10146[J]

[21] DaneshkhahM, HossainiH, MalakootianM. Removal of metoprolol from water by sepiolite-supported nanoscale zero-valent iron. Journal of Environmental Chemical Engineering, 2017, 5(4): 3490-3499[J]

[22] HabishA J, LazarevićS, Janković-ČastvanI, et al.. Nanoscale zerovalent iron (nZVI) supported by natural and acid-activated sepiolites: The effect of the nZVI/support ratio on the composite properties and Cd²⁺ adsorption. Environmental Science and Pollution Research, 2017, 24(1): 628-643[J]

[23] FuR-b, YangY-p, XuZ, et al.. The removal of chromium (VI) and lead (II) from groundwater using sepiolite-supported nanoscale zero-valent iron (S-NZVI). Chemosphere, 2015, 138: 726-734[J]

[24] RajaS, KolaA K, BalakrishnanD, et al.. Adsorptive removal of azo dye using magnetic nanoparticles: An insight into equilibrium, kinetics and thermodynamic studies. Applied Nanoscience, 2024, 14(1): 123-134[J]

[25] WuY-j, ZhangJ-h, TongY-f, et al.. Chromium(VI) reduction in aqueous solutions by Fe₃O₄-stabilized Fe⁰ nanoparticles. Journal of Hazardous Materials, 2009, 172(2–3): 1640-1645[J]

[26] TanL, LuS-y, FangZ-q, et al.. Enhanced reductive debromination and subsequent oxidative ring-opening of decabromodiphenyl ether by integrated catalyst of nZVI supported on magnetic Fe₃O₄ nanoparticles. Applied Catalysis B: Environmental, 2017, 200: 200-210[J]

[27] LvZ-m, YangS-m, ChenL, et al.. Nanoscale zero-valent iron/magnetite carbon composites for highly efficient immobilization of U(VI). Journal of Environmental Sciences, 2019, 76: 377-387[J]

[28] GongL, QiJ-l, LvN, et al.. Mechanistic role of nitrate anion in TCE dechlorination by ball milled ZVI and sulfidated ZVI: Experimental investigation and theoretical analysis. Journal of Hazardous Materials, 2021, 403123844[J]

[29] ShiC-l, ZhangS-l, ZhaoJ-f, et al.. Experimental study on removal of microplastics from aqueous solution by magnetic force effect on the magnetic sepiolite. Separation and Purification Technology, 2022, 288120564[J]

[30] SunS, HuangJ-q, WenJ, et al.. Sepiolite-supported nanoscale zero-valent iron alleviates Cd&As accumulation in rice by reducing Cd&As bioavailability in paddy soil and promoting Cd&As sequestration in iron plaque. Environmental Technology & Innovation, 2024, 33103540[J]

[31] HuongN T, NamD T, NhanN T, et al.. Synthesis of PEG-Fe₃O₄/ZnO magnetic nanocomposites by ultrasound assisted co-precipitation process and their antibacterial activity. Asian Journal of Chemistry, 2020, 33(1): 215-219[J]

[32] YanW-l, HerzingA A, KielyC J, et al.. Nanoscale zero-valent iron (nZVI): Aspects of the core-shell structure and reactions with inorganic species in water. Journal of Contaminant Hydrology, 2010, 118(3): 96-104[J]

[33] JiangC-l, WangR, ChenX, et al.. Preparation of chitosan modified fly ash under acid condition and its adsorption mechanism for Cr(VI) in water. Journal of Central South University, 2021, 28(6): 1652-1664[J]

[34] MaX, DuanG-y, HuangJ-q, et al.. Preparation of graphene oxide/polyiminodiacetic acid resin as a high-performance adsorbent for Cu(II). Journal of Central South University, 2023, 30(12): 3881-3896[J]

[35] WeiB-h, XueZ-y, YangY-d, et al.. Preparation of tungsten slag-bentonite particle adsorbent and its adsorption performance for lead ion from wastewater. Journal of Central South University, 2023, 30(6): 1841-1855[J]

[36] ShiT-s, JiangF, WangP, et al.. Deep purification of As(V) in drinking water by silica gel loaded with FeOOH and MnO₂. Journal of Central South University, 2021, 28(6): 1692-1706[J]

[37] ShahidM K, PhearomS, ChoiY G. Synthesis of magnetite from raw mill scale and its application for arsenate adsorption from contaminated water. Chemosphere, 2018, 203: 90-95[J]

[38] YusmartiniE S, Ridwan, SetiabudidayaD, et al.. Synthesis and characterizations of nZVI-AC composites from coconut shells and its application for the adsorption of Pb(II) and Cr(VI) ions. IOP Conference Series: Materials Science and Engineering, 2019, 509012042[J]

[39] FrostR L, XiY-f, HeH-p. Synthesis, characterization of palygorskite supported zero-valent iron and its application for methylene blue adsorption. Journal of Colloid and Interface Science, 2010, 341(1): 153-161[J]

[40] SinghV, KaulS, SinglaP, et al.. Xylanase immobilization on magnetite and magnetite core/shell nanocomposites using two different flexible alkyl length organophosphonates: Linker length and shell effect on enzyme catalytic activity. International Journal of Biological Macromolecules, 2018, 115: 590-599[J]

[41] AkyuzS, AkyuzT, AkalinE. Adsorption of isoniazid onto sepiolite – palygorskite group of clays: An IR study. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2010, 75(4): 1304-1307[J]

[42] XieA-j, TangY-r, HuangX-y, et al.. Three-dimensional nanoflower MnCrO x/Sepiolite catalyst with increased SO₂ resistance for NH₃-SCR at low temperature. Chemical Engineering Journal, 2019, 370: 897-905[J]

[43] HabibI, PaoC W, ChuangY-c, et al.. Dinitrosyl iron complex-derived nanosized zerovalent iron (NZVI) as a template for the Fe – co cracked NZVI: An electrocatalyst for the oxygen evolution reaction. Inorganic Chemistry, 2024, 63(1): 784-794[J]

[44] TeferaM, FekaduR, EsheteF F, et al.. Visible-light-driven reduction of chromium (VI) by green synthesised cuprous oxide nanoparticles. Journal of Molecular Liquids, 2022, 359119272[J]

[45] YangX, LiuL-h, ZhangM-z, et al.. Improved removal capacity of magnetite for Cr(VI) by electrochemical reduction. Journal of Hazardous Materials, 2019, 374: 26-34[J]

[46] QuG-z, ZengD-y, ChuR-j, et al.. Magnetic Fe₃O₄ assembled on nZVI supported on activated carbon fiber for Cr(VI) and Cu(II) removal from aqueous solution through a permeable reactive column. Environmental Science and Pollution Research International, 2019, 26(5): 5176-5188[J]

[47] MaoL-q, WangJ, ZengM, et al.. Temperature dependent reduction of Cr(VI) to Cr(V) aroused by CaO during thermal treatment of solid waste containing Cr(VI). Chemosphere, 2021, 262127924[J]

[48] LiY, HuangT, LiuX-l, et al.. Sorption-catalytic reduction/extraction of hexavalent Cr(VI) and U(VI) by porous frameworks materials. Separation and Purification Technology, 2023, 314123615[J]

[49] LuoW-g, ZengZ, BianL. Effect of lattice substitution on adsorption of hexavalent chromium by montmorillonite, nontronite, and beidellite. Minerals, 2021, 11121407[J]

[50] RathinamK, AtchudanR, Jebakumar Immanuel EdisonT N. Zirconium oxide intercalated sodium montmorillonite scaffold as an effective adsorbent for the elimination of phosphate and hexavalent chromium ions. Journal of Environmental Chemical Engineering, 2021, 95106053[J]

[51] DebA K, BiswasB, NaiduR, et al.. Mechanistic insights of hexavalent chromium remediation by halloysite-supported copper nanoclusters. Journal of Hazardous Materials, 2022, 421126812[J]

[52] WangJ-h, SunT-t, SaleemA, et al.. Enhanced adsorptive removal of Cr(VI) in aqueous solution by polyethyleneimine modified palygorskite. Chinese Journal of Chemical Engineering, 2020, 28(10): 2650-2657[J]

[53] ZhangX-j, LiY-l, ZouW-j, et al.. Preparation of composite porous hydrogel montmorillonite/humic acid/polyvinyl alcohol@polypyrrole based on Pickering emulsion template method for enhancing hexavalent chromium ions adsorption from aqueous solution. Journal of Inorganic and Organometallic Polymers and Materials, 2024, 34(2): 745-758[J]

[54] PechishchevaN V, EstemirovaS K, KimA V, et al.. Adsorption of hexavalent chromium on mechanically activated graphite. Diamond and Related Materials, 2022, 127109152[J]

[55] DongH-r, ZhaoF, HeQ, et al.. Physicochemical transformation of carboxymethyl cellulose-coated zero-valent iron nanoparticles (nZVI) in simulated groundwater under anaerobic conditions. Separation and Purification Technology, 2017, 175: 376-383[J]

[56] LiuA-r, LiuJ, PanB-c, et al.. Formation of lepidocrocite (γ-FeOOH) from oxidation of nanoscale zero-valent iron (nZVI) in oxygenated water. RSC Advances, 2014, 4(101): 57377-57382[J]

[57] ZhouX-b, JingG-h, LvB-h, et al.. Highly efficient removal of chromium(VI) by Fe/Ni bimetallic nanoparticles in an ultrasound-assisted system. Chemosphere, 2016, 160: 332-341[J]

[58] RenJ-j, ZhengL-c, SuY-m, et al.. Competitive adsorption of Cd(II), Pb(II) and Cu(II) ions from acid mine drainage with zero-valent iron/phosphoric titanium dioxide: XPS qualitative analyses and DFT quantitative calculations. Chemical Engineering Journal, 2022, 445136778[J]

[59] HaoT-w, LiuK, GaoB-l, et al.. Phase transformation of nanosized zero-valent iron modulated by As(III) determines heavy metal passivation. Water Research, 2022, 221118804[J]

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