Exploring the iron oxide functionalized biobased carbon-silica-polyethyleneimine composites for hexavalent chromium removal from dilute aqueous solutions

Mpho Cynthia Qhubu, Philiswa Nosizo Nomngongo, Vusumzi Emmanuel Pakade

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)

Abstract

The contamination of water resources by toxic hexavalent chromium remains a challenge. In this study, amino-functionalized iron oxide biobased carbon-silica composites were prepared through co-precipitation of Fe (II) and Fe (III) over Macadamia activated carbon and explored as feasible adsorbents for the removal of Cr(VI) from dilute aqueous solutions. The energy dispersive spectroscopy (EDS) elemental analysis confirmed the existence of Fe, Si, O, and C atoms, which form the backbone of the composite. The FTIR also showed the presence of Fe-O and Si-O-Si and Si-OH spectral bands, affirming the backbone of the adsorbents. Cr(VI) adsorption efficiency (5.76 mg/g) was achieved at pH 1 when an initial concentration of 2.5 mg/L, contact time of 90 min, and dosage concentration of 1.7 g/L were used. The data were best described by the Langmuir adsorption model and pseudo-second-order rate model. ΔG° (−3 to −12 kJ/mol) and ΔH° (46, 12 and 5 kJ/mol) values affirmed that the adsorption of Cr(VI) was spontaneous and endothermic and dominated by chemical interactions.

Original languageEnglish
Article number3081
JournalWater (Switzerland)
Volume13
Issue number21
DOIs
Publication statusPublished - 1 Nov 2021

Keywords

  • Activated carbon
  • Adsorption
  • Chromium (VI)
  • Co-precipitation
  • Functionalization
  • Iron oxide

ASJC Scopus subject areas

  • Geography, Planning and Development
  • Biochemistry
  • Aquatic Science
  • Water Science and Technology

Fingerprint

Dive into the research topics of 'Exploring the iron oxide functionalized biobased carbon-silica-polyethyleneimine composites for hexavalent chromium removal from dilute aqueous solutions'. Together they form a unique fingerprint.

Cite this