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Keywords:

  • composites;
  • PAAc-AN-TV;
  • kinetics;
  • Isotherms;
  • double shell model and thermodynamics

Abstract

A novel composite, composed of poly (acrylic acid (AAc), acrylonitrile, and titanium vanadate, was prepared by induced gamma irradiation route at 20 kGy to be used as a hybrid organic-inorganic sorbent. 5–200 μm particle diameters of the composite were obtained. An average particle size of 75 μm of crystalline (17-20) composite was used; it was thermally stable to 486°C. The distribution coefficients of Cs+ and Eu3+ were studied as a function of pH; 2350 mL·g−1 and 645 mL·g−1 were obtained in case of 152+154Eu and 134Cs at pH 6. 1.55 mmol·g−1 and 1.85 mmol·g−1 maximum loadings were accommodated for the same ions at the same pH. Different models were used to scan the surface of the exchanger, so that the topography of the surface was studied as a function of surface active site types, concentrations, and heterogeneity. Langmuir, Freundlich and D-R models were used. Also, different kinetic models, as Lagergren pseudo first-order, pseudo second-order and Morris-Weber intraparticle diffusion models were applied to study the possible mechanism of the sorption process; pseudo first-order was exempted to investigate the mechanism. They proved that chemisorption and ion exchange mechanism with controlled diffusion are predominant, with their characteristic mean energies (8.731 kJ·mol−1 and 9.310 kJ·mol−1 for Cs+ and Eu3+, respectively). Double Shell Model was finally adopted to explain the suggested mechanism. Negative values of ΔG°, −2.15 kJ·mol−1 to −7.92 kJ·mol−1 in case of Cs+ and −3.35 kJ·mol−1 to −9.67 kJ·mol−1 in case of Eu3+adsorption at different temperatures, indicate the spontaneous nature of the reactions. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009