عنوان مجله
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IRANIAN JOURNAL OF CHEMISTRY & CHEMICAL ENGINEERING-INTERNATIONAL ENGLISH EDITION
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چکیده
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The sorption of thorium and uranium ions by functionalized SBA–15 mesoporous
silica materials with Schiff base ligating groups N–propylsalicylaldimine (SBA/SA) and
ethylenediaminepropylesalicylaldimine (SBA/EnSA) from aqueous solution was investigated
in fixed-bed column method. The effect of pH, sample solution volume, and the column design
parameters such as sample and eluent flow rates, and column bed height were studied. These
investigations allowed to obtain the experimental breakthrough curves. Regardless to the adsorbent
used, application of the columns with 2.5 cm bed height and sample flow rate 0.4 mL/min, resulted
in the quantitative removal of 0.5 mg of Th(IV) and U(VI) ions from 200 and 250 mL aqueous
solutions, adjusted at pH 4. The quantitative desorption of the loaded ions provided
a preconcentration factor of 40 and 50 for Th(IV) and U(VI), respectively. Breakthrough studies
showed the higher capacity of the column packed with SBA/EnSA in comparison to that packed with
SBA/SA. The breakthrough curves indicated that both of the sorbents presents higher capacity
towards uranium than thorium ions. The columns could be used for at least 3 sorption-desorption
cycles. The investigated columns were examined for the recovery of Th(IV) and U(VI) from
tap water and seawater samples.
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