Utilisation of environmentally friendly okara-based biosorbent for cadmium(II) removal

Billie Yan Zhang Hiew, Lai Yee Lee*, Xin Jiat Lee, Suchithra Thangalazhy-Gopakumar, Suyin Gan

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

19 Citations (Scopus)


Heavy metals released by various industries are among the major pollutants found in water resources. In this research, biosorption technique was employed to remove cadmium (Cd2+) from an aqueous system using a novel biosorbent developed from okara waste (OW), a residue from soya bean–based food and beverage processing. Characterisation results revealed that the OW biosorbent contained functional groups such as hydroxyl-, carboxyl- and sulphur-based functional groups, and the surface of the biosorbent was rough with multiple fissures which might be the binding sites for the pollutant. The effects of dosage, solution pH, initial Cd2+ concentration, temperature and contact time were investigated using batch adsorption mode. The biosorption equilibrium and kinetic were best described by the Langmuir and Elovich models, respectively. The maximum biosorption capacities predicted by the Langmuir model were 10.91–14.80 mg/g at 30–70 °C, and the biosorption process was favourable as evident from 0 < RL < 1. The uptake of Cd2+ by the OW biosorbent was spontaneous and endothermic. The plausible biosorption mechanisms of this study could be ionic exchange, hydrogen bonding and electrostatic interactions. The Cd2+ loaded OW biosorbent could be regenerated using 0.4 M of HCl solution and regeneration was studied for 4 adsorption-desorption cycles. The present investigation supported that OW can be reused as a value-added biosorbent product for the removal of Cd2+ from the contaminated water.

Original languageEnglish
Pages (from-to)40608-40622
Number of pages15
JournalEnvironmental Science and Pollution Research
Issue number30
Early online date29 Jun 2020
Publication statusPublished - Aug 2021


  • Biosorption mechanism
  • Cadmium removal
  • Equilibrium and kinetic
  • Okara waste biosorbent

ASJC Scopus subject areas

  • Environmental Chemistry
  • Pollution
  • Health, Toxicology and Mutagenesis


Dive into the research topics of 'Utilisation of environmentally friendly okara-based biosorbent for cadmium(II) removal'. Together they form a unique fingerprint.

Cite this