논문 상세보기
pp.542-550
The objective of this study was to evaluate the immobilization efficiency and sequential extraction of soluble phosphates (Na2HPO4 ·12H2O, Ca(H2PO4)2 ·H2O, (NH4)2HPO4) for the stabilization of heavy metals (Cu, Pb, Zn and Cd) in abandoned mine soil. The application rate of stabilizers to soils was determinated PO4/Pbtotal molar ratio of 0.5, 1.0, 2.0, 4.0. The immobilization efficiency was evaluate of TCLP (EPA method 1311) used in a landfill for heavy metals. After processing stabilization, the immobilization efficiency of Pb is more than 95% at molar ratio of 2.0 regardless kind of phosphate. For Cu Zn and Cd, on the other hand, the efficiency has the range of from 30% to 50%, even though molar ratio increase up to 4.0. It is relatively low in comparison with Pb. Leachability of heavy metals was reduced with increasing amounts of added phosphate. Phosphates, Na2HPO4 ·12H2O was more immobilization than Ca(H2PO4)2 ·H2O, (NH4)2HPO4. After sequential extraction, form of heavy metals in soil tends to increase strongly bond like forms of organic matter-bound(F4) and residual (F5). Especially the stable residual form increases in all metals. The growth rate of residual fraction was a little different heavy metals. The growth rate of Zn is greatest increased from 17% to 22% than other metals, it was followed by Zn > Cd > Pb > Cu. Phosphates, Ca(H2PO4)2 ·H2O was the greatest increased for residual fraction.
