Adsorptive Properties Of Modified Clays
ADSORPTIVE PROPERTIES OF MODIFIED CLAYS
E. Komorowska - Czepirska
University of Mining and Metallurgy, Faculty of Fuels and Energy,
al. Mickiewicza 30, 30-059 Cracow, Poland
Natural clay minerals are a matter of interest on account of their specific properties such as sorption characteristics as well as susceptibility to physico-chemical modification. Generally, the raw clays show relatively low adsorption capacity and low selectivity what causes that the number of works is connected with elaboration of the ways for their modification in order to obtain product with desired properties. The well-known methods of modification are: cation exchange, acid activation, and hydrofobization by organic compounds, intercalation with metal-hydroxycations. A novel idea to obtain a new type of sorbent is using of smectites as template to prepare so called carbon-mineral adsorbents. It seems that layered framework, small interlayer spacing, ion-exchange properties, various porosity in smectites are factors that can make it possible to control syntheses and final properties of products of modification.
Smectites intercalated with aluminum hydroxycations with various Al/OH ratios were prepared in this study and next characterized by adsorption methods.
The adsorption equilibria and kinetics of different organic vapors were studied in wide range of temperature and pressure. The mechanism of diffusion (temperature and pressure dependence of diffusion coefficients) is analyzed for aromatic hydrocarbons as well as alcohols.
Pillared clays were also used to prepare mineral – carbon adsorbents by means of carbon component deposition on mineral support. Carbon component was produced by polycondensation and carbonization of furfuryl alcohol on clay. Adsorptive properties of produced sorbents have been tested.
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