title: Synergistic effects of the combination of oxalate and ascorbate on arsenic extraction from contaminated soils.
abstract: Arsenic is often associated with iron oxides in soils due to its high affinity with iron oxides and the abundance of iron oxides in the environment. Dissolution of iron oxides can subsequently release arsenic associated with them into the environment, which results in the increase of arsenic mobility in the soil environment. In this study, arsenic extraction from soils via the dissolution of iron oxides was investigated using oxalate, ascorbate, and their combination in order to effectively remediate arsenic-contaminated soils. Oxalate mainly extracted iron from soils via a ligand-promoted reaction, while ascorbate extracted iron mainly via a reductive reaction. Arsenic extractions from soils by oxalate and ascorbate were shown to behave similarly to iron extractions, indicating the concurrent release of arsenic adsorbed on iron oxides upon the dissolution of iron oxides. The combination of oxalate and ascorbate greatly increased arsenic extraction, indicating the synergistic effects of the combination of oxalate and ascorbate on iron and arsenic extraction from soils. Oxalate and ascorbate are naturally-occurring organic reagents that have chelating and reducing capacity. Therefore, the use of oxalate and ascorbate is environmentally friendly and effective for the remediation of arsenic-contaminated soils.
authors.affiliation: Department of Environmental Engineering and Soil Environment Research Center, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabuk-do 54896, Republic of Korea.
authors.forename: Jae-Cheol
authors.initials: JC
authors.lastname: Lee
authors.affiliation: Department of Environmental Engineering, Mokpo National University, 1666 Yongsan-ro, Cheongye-myeon, Muan-gun, Jeollanam-do 58554, Republic of Korea. Electronic address: ejkim@mokpo.ac.kr.
authors.forename: Eun Jung
authors.initials: EJ
authors.lastname: Kim
authors.affiliation: Department of Environmental Engineering and Soil Environment Research Center, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabuk-do 54896, Republic of Korea; Department of Bioactive Material Sciences, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabuk-do 54896, Republic of Korea. Electronic address: kbaek@jbnu.ac.kr.
authors.forename: Kitae
authors.initials: K
authors.lastname: Baek
mesh_terms: D000327:Adsorption; D001151:Arsenic / Q000032:analysis* / Q000737:chemistry; D001205:Ascorbic Acid / Q000737:chemistry*; D002614:Chelating Agents / Q000737:chemistry; D004787:Environmental Pollution; D052918:Environmental Restoration and Remediation / Q000379:methods; D005290:Ferric Compounds / Q000737:chemistry; D007501:Iron / Q000032:analysis; D008956:Models, Chemical; D010070:Oxalates / Q000737:chemistry*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis* / Q000737:chemistry
chemical_list: D002614:Chelating Agents; D005290:Ferric Compounds; D010070:Oxalates; D012987:Soil; D012989:Soil Pollutants; C000499:ferric oxide; D007501:Iron; D001151:Arsenic; D001205:Ascorbic Acid
keywords: Arsenic; Ascorbate; Iron oxide dissolution; Oxalate; Soil