Bøger af Fawwaz Khalili

Pollution in our planet by heavy metals is an important environmental problem threatening the health of human populations and natural ecosystems. Agricultural and industrial pollution release large amounts of heavy metals into the atmosphere, surface water, soil, and plants. The aim of this research work is to determine the potential of application of sodium polyphosphate modified kaolinite clay as an adsorbent for the removal of lead (II), zinc (II) and cadmium (II) ions from aqueous solutions. The adsorbent dosage, pH, temperature and contact time were investigated. The adsorption isotherms of all three metal ions followed well Langmuir equation. Modified sodium polyphosphate-kaolinite clay was found to remove heavy metal ions efficiently from aqueous solutions with selectivity in the order of Pb2+ > Zn2+ > Cd2+. The maximum heavy metal ions adsorbed by modified. The results of this study showed that the sodium polyphosphate-kaolinite clay powder can be efficiently used as a low-cost adsorbent for the removal of divalent lead, zinc and cadmium from aqueous solution.

Shorttitle Humic Acid (HA) is an important constituent of soil organic matter which was the subject of several environmental studies. In this work the adsorption isotherms of Thorium(IV) and Uranium(VI) onto Azraq Humic acid (AZHA) were studied at different temperature and pH values. The results indicate that Thorium(IV) has higher adsorptivity than Uranium(VI). The increasing of pH resulted in higher adsorptivity of Actinides. In contrast to heavy metals and Lanthanides (entropy driven), the adsorption of Actinides on HA was found to be exothermic and so enthalpy driven. This leads to the hypothesis that Thorium(IV) and Uranium(IV) are encapsulated in the interior of HA helix with their water of hydration because the interior is full with water. However, heavy metals and Lanthanides are adsorbed on the exterior of HA helix.