Remediation of Cu-contaminated soil using chelant and EAOP.
An electrochemical advanced oxidation process (EAOP) was used for treatment of the washing solution obtained during leaching of Cu (364 +/- 2 mg kg(-1)) contaminated soil, with chelant S,S isomer of ethylenediamine disuccinate ([S,S]-EDDS). In the EAOP (constant current density 40 mA cm(-2)), a boron-doped diamond anode was used for the generation of hydroxyl radicals and oxidative decomposition of [S,S]-EDDS-metal complexes in the washing solution. The released Cu was mostly electro-deposited on the stainless-steel cathode. Three consecutive additions of 5 mmol kg(-1) [S,S]-EDDS removed 46% of the Cu from the soil, mostly from carbonate and oxide soil fractions (87 and 99% Cu reduction). The soil Cu oral availability in the simulated stomach and intestinal phases (in vitro physiologically based extraction test) was reduced by 5.5 and 4.6-times. Cu plant availability (in vitro diethylenetriamine pentaacetate test) was reduced by 3.6-times. The discharge solution was clear, almost colorless, with pH 8.4, 0.45 mg L(-1) Cu and 0.01 mM EDDS.
Agronomy Department, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia.
Maja
M
Pociecha
Helena
H
Sircelj
Domen
D
Lestan
D001682:Biological Availability; D002614:Chelating Agents / Q000737:chemistry*; D003300:Copper / Q000032:analysis* / Q000493:pharmacokinetics; D004563:Electrochemistry; D004572:Electrolysis; D052918:Environmental Restoration and Remediation / Q000379:methods*; D005029:Ethylenediamines / Q000737:chemistry; D010084:Oxidation-Reduction; D010944:Plants / Q000378:metabolism; D012989:Soil Pollutants / Q000032:analysis*; D012996:Solutions; D013386:Succinates / Q000737:chemistry
C499100:(S,S)-ethylenediaminedisuccinate; D002614:Chelating Agents; D005029:Ethylenediamines; D012989:Soil Pollutants; D012996:Solutions; D013386:Succinates; D003300:Copper