Performance and mechanism of polypeptidylated hemoglobin (Hb)/iron oxide magnetic composites for enhanced dye removal

Chemosphere. 2020 May:247:125897. doi: 10.1016/j.chemosphere.2020.125897. Epub 2020 Jan 14.

Abstract

Composites of polypeptidylated hemoglobin supported on different iron oxide weights (0.5:1 and 1:1) were developed and demonstrated to function as efficient adsorbents for Eriochrome black-T dye removal. The synthesis of these adsorbents were performed through N-carboxyanhydride (NCA) polymerization at low temperature (4 °C) and near-neutral pH for 24 h followed by chemical co-precipitation. The synthesized adsorbents were found to exhibit BET surface area (54-87 m2/g), pore volume (0.30-0.35 cm3/g), average pore diameter (160-218 Å) and average pore width (136-171 Å). The developed adsorbents were tested in a batch dye adsorption system. Adsorption was found to follow pseudo-second order kinetics and the Langmuir adsorption capacities were 123, 204 and 217 mg/g for Fe3O4, 0.5:1 and 1:1 adsorbent samples, respectively. Chemical regeneration was successfully carried out using methanol and the reusability of the adsorbents were demonstrated with a decrease in adsorption capacities from ∼49 to ∼33 mg/g after the fourth reuse.

Keywords: Dye remediation; Eriochrome black-T; Iron oxide composite; Magnetic adsorbent; Regeneration.

MeSH terms

  • Adsorption
  • Chemical Precipitation
  • Coloring Agents / chemistry*
  • Ferric Compounds / chemistry*
  • Hemoglobins / chemistry*
  • Hydrogen-Ion Concentration
  • Kinetics
  • Magnetic Phenomena
  • Magnetics
  • Water Pollutants, Chemical / chemistry*
  • Water Purification / methods*

Substances

  • Coloring Agents
  • Ferric Compounds
  • Hemoglobins
  • Water Pollutants, Chemical
  • ferric oxide