Removal of lead ions using phosphorylated sawdust

To increase the uptake capacity of lead ions, surface of sawdust were modified into phosphate groups. The phosphorylated sawdust prepared through chemical reaction with H3PO4 (85%) showed a high uptake capacity of about 1.45 mmol Pb/g-dry mass at pH 4. The component of phosphorylated sawdust was analyzed by EDX (energy dispersive X-ray) and the increase of phosphate group was confirmed. The phosphorylated sawdust had a high uptake capacity at low temperature of 10 °C and could remove lead ions of about 98% with 0.04 g of modified sawdust. Also, most of adsorption of lead ions was completed within 40 min.