Kinetic and equilibrium studies of adsorptive removal of phenol onto eggshell waste

• Published in: Environmental science and pollution research international 2013-07, Vol.20 (7), p.4603-4611
• Main Authors: Daraei, H., Mittal, A., Noorisepehr, M., Daraei, F.
• Format: Article
• Language: English
• Subjects: Adsorbents; Adsorption; Ambient temperature; Animals; Aquatic Pollution; Aqueous solutions; Atmospheric Protection/Air Quality Control/Air Pollution; Bioremediation; Earth and Environmental Science; Ecotoxicology; Egg Shell - chemistry; Egg shells; Eggs; Environment; Environmental Chemistry; Environmental Health; Fourier transforms; Free energy; Hydrogen-Ion Concentration; Infrared spectroscopy; Isotherms; Kinetics; Mathematical models; Membrane separation; Phenol - chemistry; Phenol - isolation & purification; Phenols; Physical characteristics; Pollutants; Research Article; Scanning electron microscopy; Solid wastes; Spectroscopy, Fourier Transform Infrared; Studies; Thermodynamics; Waste materials; Waste Water - analysis; Waste Water - chemistry; Waste Water Technology; Water Management; Water Pollutants, Chemical - isolation & purification; Water pollution; Water Pollution Control; Water Purification - methods; X-Ray Diffraction; X-ray fluorescence
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-012-1409-8

The aim of the present research is to develop economic, fast, and versatile method for the removal of toxic organic pollutant phenol from wastewater using eggshell. The batch experiments are conducted to evaluate the effect of pH, phenol concentration, dosage of adsorbent, and contact time on the removal of phenol. The paper includes in-depth kinetic studies of the ongoing adsorption process. Attempts have also been made to verify Langmuir and Freundlich adsorption isotherms. The morphology and characteristics of eggshell have also been studied using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and X-ray fluorescence analysis. At ambient temperature, the maximum adsorption of phenol onto eggshells has been achieved at pH 9 and the contact time, 90 min. The experimental data give best-fitted straight lines for pseudo-first-order as well as pseudo-second-order kinetic models. Furthermore, the adsorption process verifies Freundlich and Langmuir adsorption isotherms, and on the basis of mathematical expressions of these models, various necessary adsorption constants have been calculated. Using adsorption data, various thermodynamic parameters like change in enthalpy (∆ H 0 ), change in entropy (∆ S 0 ), and change in free energy ∆ G 0 have also been evaluated. Results clearly reveal that the solid waste material eggshell acts as an effective adsorbent for the removal of phenol from aqueous solutions.