論説報文
EDTAおよびEDDSによる汚染土壌からの鉛の抽出
2009 年 56 巻 2 号 p. 64-67
詳細
2009 年 56 巻 2 号 p. 64-67
The biodegradable chelating agents [S,S]-ethylenediaminedisuccinic acid (EDDS) and the low biodegradable chelating agent ethylenediaminetetraacetic acid (EDTA) were investigated for their removal efficiency of lead from soil by soil washing.
In the soil washing tests, the removal efficiency of lead with EDTA was high in the wide pH range and the efficiency of lead removal with EDDS increased with increasing pH. However, EDDS has no effect on the removal of lead in the acidic region below pH 5.5. Acid contribution was predominant for the removal of lead with EDDS below pH 5.5 and the complexation between EDDS and lead were negligible.
The reaction rates for extraction of lead with EDTA and EDDS were represented by the volume reaction model. The activation energies of these extraction reactions are over 55 kJ/mol and the apparent reaction rate constants are not affected by the stirring speeds, therefore it is considered that these extraction reactions are chemically controlled.
