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Novel Multifunctional Mesoporous Microsphere with High Surface Area for Removal of Zinc Ion from Aqueous Solution: Preparation and Characterization

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Abstract

Amino-functionalized magnetic mesoporous microsphere has been successfully synthesized through a two-step coating process of silica on a magnetic core (Fe3O4). In the synthesis process, cetyltrimethyl ammoniumbromide (CTAB) was used as a structure-directing agent and it was removed by combination of solvent extraction and calcination modified processes. In this method, mesoporous silica shell with higher surface area was formed which could facilitate the loading of much more amino groups and the capacity to adsorb more heavy metal ions such as Zn2+ was provided. Different amounts of 3-aminopropyl triethoxysilane (APTES) were examined in order to obtain an optimum amount of amino groups which can be grafted on Fe3O4/SiO2/meso-SiO2 microsphere. The resultant multifunctional microsphere was characterized by field emission scanning electron microscope, transmission electron microscope, FTIR spectrophotometer, X-ray diffraction, vibration sample magnetometer, thermogravimetric analysis, nitrogen adsorption–desorption and particle size analyzer. Comparing to functionalized amino group on traditional magnetic mesoporous silica, the as-prepared microsphere not only exhibited higher specific surface area (617.31 m2 g−1) but also demonstrated higher adsorption capacity for Zn(II) (270.2703 mg g−1 at 25 °C). Important of all, the adsorbent was simply removed from sample solution by magnetic field and it was regenerated by acid treatment.

Graphical Abstract

Synthetic route of Fe3O4/SiO2/meso-SiO2–NH2 and its use for Zn(II) ions removal.

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Acknowledgements

The authors are grateful to Dr. Ghodratollah Absalan, Professor Masoumi Laboratory, Department of chemistry, collage of science, Shiraz University, for his kind assistance.

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  1. Department of Chemical Engineering, School of Chemical and Petroleum Engineering, Shiraz University, Shiraz, 71348-51154, Iran

    Zeinab Kheshti & Shadi Hassanajili

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Kheshti, Z., Hassanajili, S. Novel Multifunctional Mesoporous Microsphere with High Surface Area for Removal of Zinc Ion from Aqueous Solution: Preparation and Characterization. J Inorg Organomet Polym 27, 1613–1626 (2017). https://doi.org/10.1007/s10904-017-0621-x

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