Efficient removal of chromate from wastewater using a one-pot synthesis of chitosan cross-linked ceria incorporated hydrous copper oxide bio-polymeric composite

Int J Biol Macromol. 2024 Sep;276(Pt 2):134016. doi: 10.1016/j.ijbiomac.2024.134016. Epub 2024 Jul 18.

Abstract

Remediating hexavalent chromium [Cr(VI)] from contaminated water systems is a significant concern due to its harmful effects on human health, aquatic life, and plants. To tackle this issue, scientists have created a chitosan cross-linked hydrous ceria incorporated cupric oxide bio-polymeric composite (CHCCO) by combining chitosan biopolymer with corresponding metal ions using glutaraldehyde as a cross-linker. The composite was characterized using advanced analytical instruments such as FTIR, p-XRD, SEM, XPS, etc. The synthesized composite (CHCCO) was then tested for its efficiency in removing Cr(VI) from synthetic Cr(VI) aqueous samples. The parameters examined included pH, material dose, contact time, concentration, temperature, and co-existing ions. The experimental data showed that the kinetics and equilibrium data fit well with the pseudo-second-order and the Freundlich isotherm models, respectively. Thermodynamic analysis demonstrated that the investigated surface adsorption process is spontaneous and endothermic. Except for the SO42- ion, no other species imparts adverse influence significantly on the reaction. The CHCCO bio-composite surfaces were refreshed using a dilute NaOH (1.0 M) solution and effectively recycled five times for Cr(VI) adsorption, indicating no significant surface activity deterioration. This study highlights the high effectiveness of CHCCO bio-polymeric composites in Cr(VI) remediation and the potential for this technology as an easy-to-use technique for environmental restoration.

Keywords: Bio-polymeric composite; Ceria‑copper oxide; Chitosan; Cr(VI) adsorption; Cross-linking; Isotherm; Kinetics.

MeSH terms

  • Adsorption
  • Chitosan* / chemistry
  • Chromates* / chemistry
  • Chromates* / isolation & purification
  • Chromium / chemistry
  • Chromium / isolation & purification
  • Copper / chemistry
  • Cross-Linking Reagents / chemistry
  • Hydrogen-Ion Concentration
  • Kinetics
  • Temperature
  • Thermodynamics
  • Wastewater* / chemistry
  • Water Pollutants, Chemical* / chemistry
  • Water Pollutants, Chemical* / isolation & purification
  • Water Purification* / methods

Substances

  • Chitosan
  • Wastewater
  • Water Pollutants, Chemical
  • Chromates
  • Chromium
  • chromium hexavalent ion
  • Copper
  • Cross-Linking Reagents