Adsorption characteristics of natural zeolites as solid adsorbents for phenol removal from aqueous solutions: Kinetics, mechanism, and thermodynamics studies

Rushdi I. Yousef, Bassam El-Eswed, Ala'a H. Al-Muhtaseb

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320 Citations (Scopus)


Zeolitic tuff was used for the adsorption of phenol from aqueous solutions at different temperatures in a batch process. The adsorption characteristics, i.e., kinetics, mechanism, isotherms, and thermodynamics, of phenol from water onto zeolite were studied. Three different kinetic models, viz., pseudo-first-order, pseudo-second-order, and intraparticle diffusion were used to fit the kinetics data. The pseudo-second-order model best described the experimental data. Concerning the mechanism, the results indicated that the intraparticle diffusion is not the rate limiting step in the phenol adsorption process. The adsorption isotherms at different temperatures were determined and modeled using four different models. The best-fitted adsorption isotherm models were found to be in the order: Freundlich > Redlich-Peterson > Langmiur > Temkin for temperature range 25-45 °C. The Langmiur model fitted well the experimental data with a maximum adsorption capacity of 34.5, 24.9, 23.8, and 23.3. mg/g at 25, 35, 45, and 55 °C. Thermodynamically, it was determined that the adsorption of phenol onto zeolite is physical in nature and enthalpy driven with Δ H° = -10.2. kJ/mol.

Original languageEnglish
Pages (from-to)1143-1149
Number of pages7
JournalChemical Engineering Journal
Issue number3
Publication statusPublished - Jul 15 2011



  • Adsorption
  • Adsorption isotherms
  • Adsorption kinetics
  • Adsorption thermodynamics
  • Phenol
  • Zeolitic tuff

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Chemistry(all)
  • Industrial and Manufacturing Engineering
  • Environmental Chemistry

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