Gellan gum-alginate/PVA-co-PAM crosslinked hydrogel for phenol adsorption: Fabrication, characterization, and performance

Int J Biol Macromol. 2026 Mar:350:150967. doi: 10.1016/j.ijbiomac.2026.150967. Epub 2026 Feb 18.

Abstract

This study explores the synthesis, characterization, and application of a Gellan Gum/Sodium Alginate-based Poly (vinyl alcohol)-co-Polyacrylamide Cross-Linked (GG/SA-PVA-co-PAM-CL) hydrogel for phenol removal. The hydrogel was synthesised through free radical graft copolymerization with N, N'-methylene-bis-acrylamide as the crosslinker. It exhibited excellent swelling ability and structural stability. FTIR analysis confirmed the presence of functional groups, including carboxyl (1601.92 cm-1), hydroxyl (3218.10 cm-1), and amide (613.40 cm-1), supporting successful polymer integration, while XRD revealed a combination of crystalline and amorphous regions. FESEM and EDX confirmed a porous morphology with uniform elemental distribution, and TGA demonstrated good thermal stability. Adsorption studies indicated an optimal phenol uptake capacity of 78.0 mg/g at pH 6 with phenol concentration of 50 ppm at 25 °C, following the Sips isotherm and pseudo-second-order kinetics, with thermodynamic analysis suggesting an exothermic process. The hydrogel retained more than 75% adsorption efficiency after five regeneration cycles. These findings demonstrate that the GG/SA-PVA-co-PAM-CL hydrogel is a promising and reusable material for efficient phenol removal from wastewater.

Keywords: Adsorption; Alginate; Gellan gum; Hydrogel; Phenol.

MeSH terms

  • Acrylic Resins* / chemistry
  • Adsorption
  • Alginates* / chemistry
  • Cross-Linking Reagents / chemistry
  • Hydrogels* / chemistry
  • Hydrogen-Ion Concentration
  • Kinetics
  • Phenol* / chemistry
  • Phenol* / isolation & purification
  • Polysaccharides, Bacterial* / chemistry
  • Polyvinyl Alcohol* / chemistry
  • Spectroscopy, Fourier Transform Infrared
  • Temperature
  • Thermodynamics
  • Water Pollutants, Chemical / chemistry
  • Water Pollutants, Chemical / isolation & purification
  • Water Purification

Substances

  • Alginates
  • gellan gum
  • Polyvinyl Alcohol
  • Polysaccharides, Bacterial
  • Hydrogels
  • Phenol
  • Cross-Linking Reagents
  • Acrylic Resins
  • Water Pollutants, Chemical