نوع مقاله : مقاله پژوهشی
استادیار گروه مهندسی آب، دانشکده کشاورزی، دانشگاه زابل
عنوان مقاله [English]
This study examines the removal of lead from an aqueous medium using rice husk, sawdust, and sunflower stem. For this purpose, sieves No. 30 and 40 were used to obtain particles with a mean size of 500 microns from each of the absorbents. The Pb(II) solution was prepared with a concentration of 25 mg/liter before absorption tests were conducted. The results showed that the equilibrium time for rice husk was 90 min. while the same parameter for each of the other two absorbents was 120 min. An optimal absorption pH of 6 hours was obtained for each absorbent. The tests also showed that the absorption efficiency for each absorbent increased as the input lead concentration was reduced from 80 to 1mg/liter, so that the absorption efficiencies for different absorbents converged. Absorption efficiency also increased with mass. Isothermal absorption tests showed that the Tomkin model had a better fitness than the Langmuir and Freundlich models.