Application of protic ammonium-based ionic liquids with carboxylate anions for phenol extraction from aqueous solution and their cytotoxicity on human cells

Amir Sada Khan, Taleb Ibrahim*, Noor Akbar, Mustafa I. Khamis, Ruqaiyyah Siddiqui, Paul Nancarrow, Farouq Sabri Mjalli, Naveed Ahmed Khan, Nabil Abdel Jabbar

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)


In this work, the removal of phenol from aqueous solution was investigated by screening three ionic liquids (ILs) having one common cation, trioctylammonium (TOA), combined with three different anions, namely 3,4-dimethylbenzoate (IL1), 4-tert-butylbenzoate (IL2), and 4-phenylbutanoate (IL3), at room temperature. The results indicate that [TOA][4-phenylbutanoate] (IL3) gave the best efficiency and, hence, was selected for the optimization of process parameters: pH, contact time, concentration, phase ratio, and temperature. The optimum conditions were found to be pH 5, contact time of 5 min, phase ratio (VIL/Vw) of 1:5, initial concentration of phenol of 3000 ppm, and temperature of 298 K. The extraction thermodynamics were studied, and the enthalpy, entropy, and free energy of partition were evaluated. The modes of interaction of these ILs with phenol were modeled using the Conductor-Like Screening Model for Real Solvent (COSMO-RS). Additionally, the cytotoxicity of these ILs toward human cells was investigated. The results indicate that they possess less toxicity than the more commonly used 1-butyl-1-methylpyrrolidinium bis-(trifluoromethylsulfonyl)imide. It has been concluded from the experimental results that ammonium-based ILs with carboxylate anions are efficient for extraction of phenol from polluted water.

Original languageEnglish
Article number117447
JournalJournal of Molecular Liquids
Publication statusPublished - Nov 15 2021
Externally publishedYes


  • Cytotoxicity
  • Hydrophobic ionic liquids
  • Phenol

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Condensed Matter Physics
  • Spectroscopy
  • Physical and Theoretical Chemistry
  • Materials Chemistry

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