Magnetic Zr-MOFs nanocomposites for rapid removal of heavy metal ions and dyes from water
Graphical abstract
Introduction
With the rapid industrial development, accidental and purposive dumping of industrial waste such as heavy metal ions and dyes has contributed to the serious problem of water pollution, which is dangerous for the health of living organisms (Wang et al., 2014, Sun et al., 2011). Consequently, a variety of techniques have been adopted for the uptake of ions or dyes from aqueous solution, including chemical precipitation, adsorption, membrane systems and ion exchange (Hashim et al., 2011, Gupta et al., 2009, Kumar and Guliants, 2010, Dabrowski et al., 2004). Among them, adsorption featuring with simple and fast separation, efficient and low-cost has been extensively used for water treatment (Gupta and Suhas, 2009, Ali and Gupta, 2007). The choice of adsorbents largely influence the adsorption capacity and selectivity in the adsorption process to a great extent, and the low adsorption capacities and poor selective sorption have limited the application of common adsorbents (e.g. activated carbon (Mohan et al., 2008), zeolites (Meshko et al., 2001) and natural fibers (Zein et al., 2010). Therefore, development of novel adsorbents with high efficiency and selectivity for target pollutants has provoked great interest and become the main orientation in adsorption field presently. In this regard, some newly appeared materials (carbon nanotubes (Liu et al., 2013, Upadhyayula et al., 2009), graphene (Han et al., 2014, Cong et al., 2012), layered double hydroxides (Ma et al., 2014a, Ma et al., 2014b), and other materials (Taskin et al., 2014, Li et al., 2014) have been investigated as the adsorbents for heavy metals trapping, and they have exhibited great potential as the adsorbents for water treatment. While tedious high-speed centrifugation or filtration separation after adsorption is required, hindering the extensive application of such adsorbents.
Recently, widespread application of magnetic substrates to address this issue facilitates the isolation of trapped species and separation from sample solutions for reuse (Kaur et al., 2014). The combination of magnetic nanoparticles (MNPs) and desirable building blocks or components could contribute to cooperatively enhanced performance during adsorption.
Metal-Organic Frameworks (MOFs) and/or coordination polymers with permanent porosity, which were constructed through connecting inorganic metal nodes and organic building blocks via coordination bonds, have received wide attention in catalysis, gas storage and drug delivery, etc. Their excellent chemical and thermal stability, well-order porosity, high surface area and easy functionalization of their pores or outer-surface are highly favourable to adsorption (Hasan and Jhung, 2015, Burtch et al., 2014) and separation (Voorde, V. B., 2014). MOFs have been widely utilized to remove hazardous pollutants (Hasan and Jhung, 2015, Ayati et al., 2016, Roushani et al., 2016a), such as dyes or heavy metal ions in water, demonstrating a great application potential in water treatment. Magnetic MOFs composites (MFCs), which integrate the advantages of fast separation of magnetic materials and the superior properties of MOFs, have been widely used in different technological fields (Ricco et al., 2013), and offer an attractive alternative platform for dyes/heavy metal ions capture. However, a large proportion of the MFCs are functionalized with HKUST-1 currently (Zhao et al., 2015a, Zhao et al., 2015b, Xiong et al., 2015, Bagheri et al., 2012, Ke et al., 2012, Wang et al., 2013), and HKUST-1 is unstable under acid solution and would release toxic Cu2+ (Flemming and Trevors, 1989, Huang et al., 2015). Comparatively, MOFs containing zirconium metal nodes with strong Zr(IV)-O bonds exhibit better stability in water across a broad pH range (Cavka et al., 2008, Kandiah et al., 2010a, Kalidindi et al., 2015, Piscopo et al., 2015). In addition, Zr-MOFs inherit remarkable thermal and mechanical stability (Cavka et al., 2008, Wu et al., 2013). Due to the nodes with abundant Zr-bound hydroxides, Zr-MOFs exhibited excellent performance for removal of selenium species from drinking water (Howarth et al., 2015). However, the preparation/application of magnetic Zr-MOFs in water treatment is still scarce (Zhao et al., 2014, Zhang et al., 2015). Even more distressing is that the present approaches usually require specific surface modification for the in-situ growth of Zr-MOFs on the MNPs surface and the prepared MFCs are in micro-size (>200 nm). On the other hand, it has been proven that amino modification can be an effective strategy to increase the uptake of metal ions or dyes from aqueous solution (Ricco et al., 2015, Haque et al., 2010, Haque et al., 2014, Roushani et al., 2016b). So it is quite attractive to develop more simple and efficient methods to prepare amino-functionalized nano-sized Zr-MFCs.
Herein, a serious of nano-sized Zr-MFCs, including Fe3O4@SiO2@UiO-66 (denoted as MFC-O), Fe3O4@SiO2@UiO-66-NH2 (denoted as MFC-N) and Fe3O4@SiO2@UiO-66-Urea (denoted as MFC-U), have been prepared successfully through a facile one-pot hydrothermal approach (Scheme 1). All the prepared MFCs showed core-shell structure, and the shell thickness is adjustable through adjusting the quantity of predecessor. These nano-sized Zr-MFCs were investigated for the extraction of both dyes and metal ions. They exhibited excellent adsorption property both for heavy metal ions and cationic/anionic dyes, and relatively high thermal and chemical stability. Besides, fast separation and good recovery of MFCs from aqueous solution can be realized just by applying external magnetic fields, demonstrating a very good application prospect for dyes/heavy metal ions removal from environmental water.
Section snippets
Chemicals and materials
All the analytical grade chemicals were commercially available and used without further purification. The stock solution (1000 mg L−1) of Hg2+, Cd2+, Cr3+, Co2+, Mn2+, Ni2+, Pb2+, Cu2+, Zn2+ was prepared by HgCl2, Cd(NO3)2·4H2O, Pb(NO3)2, Cr(NO3)3·9H2O, Co(NO3)2·6H2O, MnCl4·4H2O, Ni(NO3)2·6H2O, CuCl2·2H2O, and Zn(NO3)2·6H2O, respectively. 1000 mg L−1 of methylene blue (MB) and methyl orange (MO) were prepared in deionized water, respectively. The solutions with desired concentration were
Materials characterization
Fig. 1(a) presents the XRD patterns of MNPs, MFC-O, MFC-N and MFC-U, respectively. The diffraction patterns of MFCs are in accordance to the published data (Kandiah et al., 2010a). The diffraction peaks at about 31° and 36° are assigned to Fe3O4 (JCPDS No. 19–0629), which demonstrate the successful introduction of Fe3O4 crystals in the hetero-nanostructure. And the characteristic peaks of the prepared MFCs are consistent with that of UiO-66, indicating that magnetic modification has no
Conclusions
In this paper, three kinds of core-shell nano Zr-MFCs with controllable encapsulating have been synthesized by facile solvothermal method. Through replacing BDC with NH2-BDC or by adding urea to the components forming UiO-66, two NH2 decorated MFCs were obtained. All the prepared Zr-MFCs are found to be efficient for heavy metal ions and organic dyes capture. The adsorption results clearly indicate that the introduction of amino groups greatly enhances the ability for metal ions/dyes capture
Acknowledgments
This work is financially supported by the National Natural Science Foundation of China (Grant Nos.: 21575107, 21575108, 21675118), the Science Fund for Creative Research Groups of NSFC (Grant No. 20921062), and the Large-Scale Instrument and Equipment Sharing Foundation of Wuhan University (LF20170799).
References (63)
- et al.
Aqueous heavy metals removal by adsorption on amine-functionalized mesoporous silica
J. Hazard Mater.
(2009) - et al.
Removal of methylene blue from aqueous solution with magnetite loaded multi-wall carbon nanotube: kinetic, isotherm and mechanism analysis
J. Hazard Mater.
(2011) - et al.
Emerging adsorptive removal of azo dye by metal–organic frameworks
Chemosphere
(2016) - et al.
Synthesis and characterization of magnetic metal-organic framework (MOF) as a novel sorbent, and its optimization by experimental design methodology for determination of palladium in environmental samples
Talanta
(2012) - et al.
Selective adsorption of cationic dyes by UiO-66-NH2
Appl. Surf. Sci.
(2015) - et al.
Selective removal of the heavy metal ions from waters and industrial wastewaters by ion-exchange method
Chemosphere
(2004) - et al.
Effect of amine modification on the properties of zirconium–carboxylic acid based materials and their applications as NO2 adsorbents at ambient conditions
Microporous Mesoporous Mater.
(2014) - et al.
Application of low-cost adsorbents for dye removal – a review
J. Environ. Manag.
(2009) - et al.
A quantum chemical study of ZrO2 atomic layer deposition growth reactions on the SiO2 surface
Surf. Sci.
(2004) - et al.
Adsorptive removal of methyl orange from aqueous solution with metal-organic frameworks, porous chromium-benzenedicarboxylates
J. Hazard Mater.
(2010)
Adsorptive removal of methyl orange and methylene blue from aqueous solution with a metal-organic framework material, iron terephthalate (MOF-235)
J. Hazard Mater.
Removal of hazardous organics from water using metal-organic frameworks (MOFs): plausible mechanisms for selective adsorptions
J. Hazard Mater.
Remediation technologies for heavy metal contaminated groundwater
J. Environ. Manag.
Fabrication of hyperbranched polyamine functionalized graphene for high-efficiency removal of Pb(II) and methylene blue
Chem. Eng. J.
Periodic mesoporous organic–inorganic hybrid materials: applications in membrane separations and adsorption
Microporous Mesoporous Mater.
Application potential of carbon nanotubes in water treatment: a review
J. Environ. Sci.
Adsorption of basic dyes on granular activated carbon and natural zeolite
Water Res.
Wastewater treatment using low cost activated carbons derived from agricultural byproducts—a case study
J. Hazard Mater.
Stability of UiO-66 under acidic treatment: opportunities and limitations for post-synthetic modifications
Microporous Mesoporous Mater.
Electroanalytical sensing of Cd2+ based on metal-organic framework modified carbon paste electrode
Sens. Actuators, B
Anionic dyes removal from aqueous solution using TMU-16 and TMU-16-NH2 as isoreticular nanoporous metal organic frameworks
J. Taiwan Inst. Chem. Eng
Magnetic responsive metal–organic frameworks nanosphere with core–shell structure for highly efficient removal of methylene blue
Chem. Eng. J.
Application of carbon nanotube technology for removal of contaminants in drinking water: a review
Sci. Total Environ.
Removal of Pb(II), Cd(II) and Co(II) from aqueous solution using Garcinia mangostana L. fruit shell
J. Hazard Mater.
Microwave-enhanced synthesis of magnetic porous covalent triazine-based framework composites for fast separation of organic dye from aqueous solution
J. Hazard Mater.
Metal-organic framework UiO-66 modified magnetite@silica core-shell magnetic microspheres for magnetic solid-phase extraction of domoic acid from shellfish samples
J. Chromatogr. A
Advances in water treatment by adsorption technology
Nat. Protoc.
Water stability and adsorption in metal-organic frameworks
Chem. Rev.
A new zirconium inorganic building brick forming metal organic frameworks with exceptional stability
J. Am. Chem. Soc.
Macroscopic multifunctional graphene-based hydrogels and aerogels by a metal ion induced self-assembly process
ACS Nano
Interactions of NO2 with Zr-based MOF: effects of the size of organic linkers on NO2 adsorption at ambient conditions
Langmuir
Cited by (242)
Core-shell design of UiO66-Fe<inf>3</inf>O<inf>4</inf> configured with EDTA-assisted washing for rapid adsorption and simple recovery of heavy metal pollutants from soil
2024, Journal of Environmental Sciences (China)Advances in adsorption of Pb(II) by MOFs-based nanocomposites in water
2024, Progress in Natural Science: Materials InternationalEfficient removal of heavy metals using 1,3,5-benzenetricarboxylic acid-modified zirconium-based organic frameworks
2024, Environmental Technology and Innovation