Adsorption of Pb (II), Cu(II) and Cr(VI) from Synthetic Solution Using Pyrolusite- Intermingled Sewage Sludge Adsorbent

A new adsorbent was developed from municipal sewage sludge (SS) combined with 5-20% pyrolusite of the weight of SS carbon, and using ZnCl₂ as chemical activation reagent. Characterized by N₂-BET methods and SEM, the result showed that the surface area of the new adsorbent was increased to 354.198 m²/g compared with that of the unmi- xed sludge activated carbon 232.526 m²/g and total pore and micropore volume were increased. The effect of various parameters on adsorption process including contact time, solution pH, amount of adsorbent and initial concentration of metal ions were studied at room temperature to optimize the conditions for maximum adsorption. The results showed that the adsorption capacities of Pb(II) ,Cu(II) and Cr (VI)by the new adsorbent could reach 13.31mg/g, 15.73 mg/g and 17.88 mg/g respectively, while the initial Pb(II) , Cu (II) and Cr (VI)concentration was 50 mg/L at the liquid /solid ratio of 1 g/L. Kinetic results were shown that the new adsorbent was better efficient materials for removing the Pb(II) ,Cu(II) and Cr (VI) from the synthetic solution, and the preferential order was equal: Pb(II) > Cu(II) > Cr (VI).