한국지하수토양환경학회 춘계학술발표회 2013년 4월 11일-12일 한화리조트 제주
2Na-EDTA로 향상된 동전기-펜톤공정에서의 펜타클로로페놀과 중금속류의 거동예측
The expected transport behavior of PCP and heavy metals in EK-Fenton process with 2Na·EDTA
문소영․이재영*
서울시립대학교 환경공학과
*e-mail : [email protected]
Abstract
This paper evaluates the effect of pH variation and chelate agent on the efficiency of electrokinetic-Fenton remediation of low permeability soils contaminated with both pentachlorophenol(PCP) and heavy metals. All experiments were performed on kaolin soil(clay mineral) which was spiked with PCP, copper and zinc in the laboratory.
The disodium ethylenediamine tetraacetic acid(2Na·EDTA) was selected as an enhancer of EK-Fenton process among citric acid, oxalic acid, 2Na·EDTA and EDTA monosodium iron(III) salt trihydrate(NaFe·EDTA). The optimal concentration of electrolyte for EK-Fenton process on kaolin soil was determined H2O2 100 mM and 2Na·EDTA 10 mM. Four types of the pretest conditions(2Na·EDTA only, H2O2 only, 2Na·EDTA with H2O2 and deionized water only) were conducted for EK-Fenton experiments with different pH. As the results, the most efficiency of degradation for PCP and heavy metals was for using 2Na·EDTA with H2O2 under wide pH range. PCP was mostly oxidized in pH 2~11, and leached out from soils caused by an ionization of PCP at pH 12. H2O2 tends to ionized over pH 11.62, so that it could make to difficult oxidizing PCP at pH 12. Also, heavy metals were removed effectively in all pH ranges, except pH 2 become of precipitation of 2Na·EDTA.The results of pretest for EK-Fenton process showed that it would be need to control acid or base front adjacent electrode and to inject the 2Na·EDTA in the process.
Key words : chelate agent, EK-Fenton, contaminant mixtures, pentachlorophenol.
