Chemical Treatment of Phosphate Slime to be used as Adsorbent for Removal of Heavy Metals from Polluted Water M.Nageeb Rashed1*, A. Rashed Mohamed2 ,M. Ahmed Awadallah2 1.Faculty of Science, Aswan University, 81528 Aswan, Egypt. Email:[email protected] 2. EL Nasr Mining Company, Edfo, Aswan, Egypt . Heavy metal pollution is a major environmental concern because of its toxicity to humans, water, soil, animals and plants. Modified phosphate slime was chemically activated by 2MHNO3. The modified adsorbent was investigated as to remove Pb, Ni, Cd, Zn and Cu from aqueous solution. The properties of activated slime phosphate before and after activation were characterized by SEM, XRF and XRD analysis. The effect of various variables (solution pH, amount of adsorbent, contact time, initial metal concentration, and temperature) on metal adsorption was investigated. Results indicated that slime phosphate activated by 2MHNO3 was selected as the best chemically activated adsorbent for Pb ,Ni, Cd, Zn and Cu adsorption. The results revealed that adsorption of the metal increased with increasing pH, adsorption dosage, initial metal concentration and solution temperature, while less significant for the effect of contact time. The sorption experimental was in a good correspondence with the Langmuir isotherms. The optimum conditions for adsorption of Pb, Ni, Cd2+, Zn and Cu were 0.5gm/100ml as adsorbent dose; 1 h contact time; 100mgl-1for Pb, Ni and Cu and 200mg/l-1 for Zn and Cd initial concentration; 60°C solution temperature; pH 5 for Pb, Cd and Cd, pH7 for Ni and Zn. The order of the maximum adsorption using activated adsorbent Zn > Pb > Ni > Cu> Cd.