Synthesis of hybrid bionanocomposites and their application for the removal of rare-earth elements from synthetic wastewater

Sidra Iftekhar, Varsha Srivastava, Mika Sillanpää

Research output: Chapter in Book/Report/Conference proceedingChapterpeer-review

18 Citations (Scopus)


In recent decades, the application of rare-earth elements (REEs) has become apparent in numerous technological sectors. The gap in the supply and demand of REEs, as well as the increasing pollution of REEs, has raised the need for the removal and recovery of these elements from both secondary sources and waste streams. Hybrid bionanocomposites synthesized using various combinations of organic-inorganic matrices have the potential to remove and recover REEs from aqueous medium. The research focuses on the synthesis of five different bionanocomposites using different organic-inorganic matrices, the characterization of prepared bionanocomposites, their application for the removal of REEs, the kinetic, isotherm, and thermodynamic studies, the determination of possible REE adsorption mechanism on bionanocomposites, and their regeneration abilities.The bionanocomposites, including cellulose-intercalated zinc-aluminum-layered double hydroxides (CL-Zn/Al LDH), sulfuric acid-modified cellulose-based silica nanocomposite (CLN/SiO2), Gum Arabic-grafted polyacrylamide-based silica (GA-g-PAM/SiO2), exfoliated biopolymeric-LDH (GA-LDH), and LDH encapsulated in xanthan gum anchored by metal ion (M@XG-ZA) nanocomposites were used to study the adsorptive behavior toward REEs. The fusion of organic-inorganic matrices combined the advantages of both matrices. The application of CL and GA with LDH for the removal of REEs exhibited promising results compared with LDH encapsulation in XG, modification of CL, and grafting of PAM chain on GA backbone with SiO2 incorporation. The selection of organic-inorganic matrix and method of synthesis is very important.The adsorption assays for the removal of REEs were performed in batch mode to attain maximum removal. The adsorption of REEs was pH dependent, and a fast removal of REEs was indicated by all bionanocomposites. The knowledge about surface properties, nature, and adsorption mechanism was attained by using different adsorption isotherm and kinetic models. Moreover, the adsorption mechanism, adsorption in a multicomponent system with or without competing ions, and intraseries adsorption behavior were also discussed. On the whole, the bionanocomposites exhibited the potential for the removal and recovery of REEs.

Original languageEnglish
Title of host publicationAdvanced Water Treatment
Subtitle of host publicationAdsorption
PublisherElsevier Inc.
Number of pages60
ISBN (Electronic)9780128192160
ISBN (Print)9780128192177
Publication statusPublished - 8 Jan 2020
Externally publishedYes


  • Adsorption
  • Adsorption isotherms
  • Adsorption kinetics
  • Adsorption mechanism
  • Bionanocomposites
  • Cellulose
  • Gum Arabic
  • Hybrids
  • Intraseries adsorption
  • Layered double hydroxides
  • Rare-earth elements
  • Silica
  • Thermodynamics
  • Xanthan gum

ASJC Scopus subject areas

  • General Engineering
  • General Chemical Engineering


Dive into the research topics of 'Synthesis of hybrid bionanocomposites and their application for the removal of rare-earth elements from synthetic wastewater'. Together they form a unique fingerprint.

Cite this