A novel magnetic sepiolite/Fe2O3 composite for adsorptive removal of lead(II) ions from aqueous solutions

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Uygun O., Murat A., ÇAKAL G. Ö.

Clay Minerals, 2023 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Basım Tarihi: 2023
  • Doi Numarası: 10.1180/clm.2023.24
  • Dergi Adı: Clay Minerals
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Aquatic Science & Fisheries Abstracts (ASFA), CAB Abstracts, Chemical Abstracts Core, Communication Abstracts, Compendex, Geobase, INSPEC, Metadex, Civil Engineering Abstracts
  • Anahtar Kelimeler: adsorption, characterization, lead, magnetic sepiolite, remediation, Sepiolite
  • Ankara Üniversitesi Adresli: Evet

Özet

Lead is one of the most frequently encountered toxic heavy metals that requires immediate remediation. To remediate wastewater, clay minerals are the preferred adsorbents. In this study, the removal of lead from aqueous solutions via adsorption was investigated using raw and iron-modified Turkish sepiolite. The aim of this study was to examine the effect of modification and environmental conditions on the sorptive properties of sepiolite samples. Initially, the raw sepiolite (Sep) and magnetic sepiolite/Fe2O3 composite (MagSep) prepared by the co-precipitation method were characterized using mineralogical and petrographical means, and the physico-chemical properties were determined. Then, the batch adsorption of lead (Pb2+) ions on the sepiolite samples were examined under various conditions (solution pH, adsorbent dosage, contact time, initial Pb2+ ion concentration, temperature, shaking rate). The adsorption capacity of MagSep was found to be higher than that of Sep under all experimental conditions. The results showed that the adsorption process followed a pseudo-second-order kinetic model, and Langmuir isotherm was the best correlation of the experimental data. The maximum adsorption capacities were found to be 60.6 mg/g and 90.1 mg/g for Sep and MagSep, respectively. The Pb-adsorbed sepiolite samples were examined with XRF, FTIR, and SEMEDS. It was seen that lead formed covalent bonds with the sepiolite samples and attached to the sepiolite surface mainly through ion exchange. In conclusion, MagSep can be efficiently used in the field of wastewater treatment for the removal of Pb2+ ions as it does not release any toxic pollutants and can be separated easily with the use of a magnetic field.