الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
The first part investigates the use of raw and chemically modified African beech sawdust for the simultaneous removal of aluminium, iron, copper, zinc and lead from aqueous solution. Batch adsorption studies were carried out at different operational conditions including: contact time, solution pH, metal ions concentrations and adsorbents loading weights. The optimum contact time was found to be 240 min. The removal percentages decreased by increasing the metal ions initial concentrations and increased with increasing the adsorbents initial loading weight and the solution pH. The point of pH zero charge was found to be 4 and 6.5 for raw and chemically treated sawdust; respectively. The spontaneous nature of the adsorption reaction was confirmed by the thermodynamic studies. The surface properties of the prepared adsorbents were characterized by BET, TGA, FT-IR and SEM analysis. The kinetic and isothermal studies suggested that the experimental data best fitted the pseudo-second-order kinetic and the Langmuir isotherm models; respectively. The recovery of the adsorbed ions was successfully achieved using different desorption solutions. In the second part, activated carbons were prepared from African beech wood sawdust by KOH activation. The activated carbons were characterized by BET, SEM, FT-IR and TGA analyses. The phenol adsorption capacity of the prepared carbons was evaluated. The different factors affecting phenol{u2019}s removal were studied including: contact time, solution pH and initial phenol concentration