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Keywords:

  • adsorption;
  • composites;
  • spectroscopy;
  • kinetics;
  • UV;
  • vis spectroscopy

Abstract

In this study, ethylene vinyl acetate–fly ash (EVA-FA) composites were prepared by the melt mixing technique using a rheomixer for the purpose of removing 2,4,6-trichlorophenol (TCP) and p-nitrophenol (PNP) from water. The fly ash was characterized by X-ray fluorescence spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD); the composites were characterized using SEM and XRD. Brunauer, Emmett, and Teller (BET) measurements revealed a surface area (SBET) of 0.07110 m2/g for the fly ash. The adsorption of TCP and PNP were monitored by UV–Vis spectrophotometer. The maximum adsorption of PNP was obtained at pH 5 after a contact period of 12 h, whereas that of the TCP was obtained at pH 4 after a period of 10 h has elapsed. The equilibrium adsorption data were evaluated using Langmuir and Freundlich adsorption isotherm models. The Langmuir adsorption model gave the better correlation coefficients for the equilibrium adsorption data. The kinetics data followed the pseudo-second-order model for both TCP and PNP. The theoretical maximum adsorption capacity (qmax) of the adsorbent used in the study was found to be 3.424 mg/g and 2.544 mg/g for TCP and PNP, respectively. The desorption of the phenols from the composites was performed using 0.2M NaOH. About 82.6% and 76.3% of TCP and PNP were recovered, respectively. The study showed that the pH of the solution and contact time play a significant role in the adsorption process. Furthermore, we have demonstrated that EVA-FA composites have the potential to adsorb phenols from acidic water solutions. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013