Use of a Hybrid Porous Carbon Material Derived from Expired Polysaccharides Snack/Iron Salt Exhibiting Magnetic Properties, for Hexavalent Chromium Removal

oleh: Maria Baikousi, Konstantinos Moustaklis, Angeliki Karakassides, Georgios Asimakopoulos, Dimitrios Moschovas, Apostolos Avgeropoulos, Athanasios B. Bourlinos, Alexios P. Douvalis, Constantinos E. Salmas, Michael A. Karakassides

Format: Article
Diterbitkan: MDPI AG 2022-04-01

Deskripsi

Nowadays, the scientific interest is focused more and more on the development of new strategies in recycling of waste products as well as on the development of clean technologies due to the increased environmental pollution. In this work we studied the valorization of an expired cheese-tomato flavor corn snack, which is polysaccharide food product, by producing advanced hybrid magnetic materials for environmental remediation purposes. The carbonization-chemical activation of this snack using potassium hydroxide leads to a microporous activated carbon with high surface area (S<sub>gBET</sub> ~800 m<sup>2</sup>/g). The magnetic hybrid material was synthesized via an in-situ technique using iron acetate complex as the precursor to produce iron based magnetic nanoparticles. The resulting material retains a fraction of the microporous structure with surface area S<sub>gBET</sub> ~500 m<sup>2</sup>/g. Such material consists, of homogenously dispersed magnetic isolated zero valent iron nanoparticles and of iron carbides (Fe<sub>3</sub>C), into the carbon matrix. The magnetic carbon exhibited high adsorption capacity in Cr(VI) removal applications following a pseudosecond order kinetic model. The maximum adsorption capacity was 88.382 mg<sub>Cr(VI)</sub>/g<sub>AC</sub> at pH = 3. Finally, oxidation experiments, in combination with FT-IR, Mössbauer, and VSM measurements indicated that the possible Cr<sup>6+</sup> removal mechanism involves oxidation of iron phases and reduction of Cr<sup>6+</sup> to Cr<sup>3+</sup>.