A. Da̧browski

Publications (5)4.21 Total impact

• Article: Heterogeneity of Polymer-Based Active Carbons in Adsorption of Aqueous Solutions of Phenol and 2,3,4-Trichlorophenol

  K. László, P. Podkościelny, A. Da̧browski
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  ABSTRACT: Heterogeneity effects that accompany adsorption of phenolic compounds from water by polymer-based activated carbons are investigated at different values of solution pH. Activated carbons prepared from poly(ethylene terephthalate) and polyacrylonitrile (APET and APAN, respectively) were used to adsorb phenol and 2,3,4-trichlorophenol in acidic (pH = 3), unbuffered, and basic (pH = 11) aqueous solutions. A Langmuir−Freundlich adsorption-isotherm equation was used to estimate the parameters that characterize adsorption of phenols from dilute solutions on heterogeneous surfaces. Adsorption energy distribution functions were calculated by a regularization method. Analysis of these functions for the APET and APAN carbons provides comparative information about their heterogeneity.
  05/2003;
• Article: New Approach to Determination of the Surface Phase Capacity in Liquid Adsorption on the Homogeneous Solid Surfaces

  A. Da̧browski, P. Podkościelny
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  ABSTRACT: Theoretical foundations are presented to analyze the errors resulting from the determination of the surface phase capacity from the excess isotherms at the solid−liquid interface. It is shown that this analysis provides the answer to the question whether the reliable results are obtained within the assumed adsorption models. Several experimental systems are analyzed to illustrate the usefulness of the presented approach.
  06/1997;
• Article: Heterogeneity of nanoporous solids in adsorption from solutions—evaluation of energy distribution functions for adsorption in micropores of activated carbons by a comparative method

  P. Podkościelny, A. Da̧browski, M. Bülow
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  ABSTRACT: The concept of a comparative method to analyse the porous structure of activated carbons by means of solid–liquid excess-adsorption isotherms is presented. This method is based on a comparison of the excess-adsorption isotherm for benzene (1) cyclohexane (2) mixtures on a nanoporous active carbon with that measured on a non-porous reference adsorbent. The proposed approach gives the possibility for estimating the maximum amounts adsorbed in the micropores and on the surface of mesopores within the nanoporous material. Consequently, the total surface phase capacity can be determined. The partial excesses for micro- and mesopores may be extracted from the total adsorption excess. As the comparative method is based on a linear equation (the so-called “n/x”-plot), a suitable statistical analysis of errors can been applied. The energy-distribution function is used to characterize heterogeneity effects. A regularization method has been employed, which takes into account the ill-posed character of the integral equation. The partial excess-adsorption isotherm, evaluated for micropores may be analyzed with regard to structural heterogeneity properties of nanoporous solids. Two series of modified active carbons, i.e. active carbons prepared from plum stones and synthetic active carbons, were used in these studies.
  Applied Surface Science 196:312-321. · 2.10 Impact Factor
• Article: Heterogeneity of active carbons in adsorption of phenol aqueous solutions

  P. Podkościelny, A. Dąbrowski, O.V. Marijuk
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  ABSTRACT: Energetic heterogeneity of activated carbons prepared from bituminous coals is investigated on the basis of adsorption isotherms of phenol from the dilute aqueous solutions. The Langmuir–Freundlich (L–F) equation has been used to estimate the monolayer capacity values of carbons studied. Adsorption energy distribution functions have been calculated by using algorithm INTEG based on a regularization method. Analysis of these functions for carbons provided significant comparative information about their heterogeneity.
  Applied Surface Science 205:297-303. · 2.10 Impact Factor
• Article: Selective removal of the heavy metal ions from waters and industrial wastewaters by ion-exchange method

  A. Da̧browski, Z. Hubicki, P. Podkościelny, E. Robens
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  ABSTRACT: By ion exchange undesirable ions are replaced by others which don't contribute to contamination of the environment. The method is technologically simple and enables efficient removal of even traces of impurities from solutions. Examples of selective removal of heavy metal ions by ion-exchange are presented. They include removal of Pb(II), Hg(II), Cd(II), Ni(II), V(IV,V), Cr(III,VI), Cu(II) and Zn(II) from water and industrial wastewaters by means various modern types of ion exchangers.
  Chemosphere.