Nanoporous Carbon Magnetic Hybrid Derived from Waterlock Polymers and Its Application for Hexavalent Chromium Removal from Aqueous Solution

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Maria Baikousi¹  Dimitrios Moschovas¹  Christina Gioti¹  Apostolos Avgeropoulos¹  Angeliki Karakassides¹  Georgios Asimakopoulos¹  Constantinos E. Salmas¹  Michael A. Karakassides¹  Athanasios B. Bourlinos²  Alexios P. Douvalis² 

[1] Department of Materials Science & Engineering, University of Ioannina, 45110 Ioannina, Greece;Physics Department, University of Ioannina, 45110 Ioannina, Greece;

关键词: carbon;    magnetic;    nanoporous;    superabsorbent polymers;    hexavalent chromium;    adsorption;   

DOI  :  10.3390/c7040069

来源: DOAJ

【 摘 要 】

Sodium polyacrylate is the superabsorbent waterlock polymer used in disposable diapers, which are the third largest single consumer item in landfills. As diapers are difficult to recycle, their use produces an incredible amount of environmental waste. In the present article, we present a reliable and facile approach to transform sodium polyacrylate, the main constitute in the used diapers, in a carbon-based magnetic sorbent material, capable for use in environmental applications. A nanoporous carbon magnetic hybrid material was prepared by reacting NaPA with iron acetate species under chemical activation conditions. Analysis of the characterization results revealed, the creation of a nanoporous structure, with high specific surface area value (S_gBET = 611 m²/g), along with the formation of nanosized zero valent iron nanoparticles and iron carbide (Fe₃C), inside the carbon pore system. ⁵⁷Fe Mössbauer spectroscopy verified also the existence of these two main iron-bearing phases, as well as additional minor magnetic phases, such as Fe₃O₄ and γ-Fe₂O₃. Vibrating sample magnetometry (VSM) measurements of the obtained hybrid confirmed its ferromagnetic/ferrimagnetic behavior. The hybrid material demonstrated a rapid sorption of Cr(VI) ions (adsorption capacity: 90 mg/g, 24 h, pH = 3). The results showed highly pH-dependent sorption efficiency of the hybrids, whereas a pseudo-second-order kinetic model described their kinetics.

【 授权许可】

Unknown