title: The effect of arsenic chemical form and mixing regime on arsenic mass transfer from soil to magnetite.
abstract: This study investigated the effect of chemical forms of arsenic (As) and soil-magnetite mixing regimes on As mass transfer in magnetite-amended soil. Two soil samples with different component ratios of As chemical forms were prepared. In the absence of magnetite, the amount of desorbable As was strongly dependent on the fraction of easily extractable As in soil. Contact of the soils with magnetite in a slurry phase significantly reduced soil As concentration for both soils. Changes in As concentrations in soil, magnetite, and water by the slurry phase contact were simulated using an As mass transfer model. The model parameters were determined independently for each process of As soil desorption and magnetite sorption. The experimentally measured As mass transfer from soil to magnetite was significantly greater than the simulation result. By sequential extraction, it was observed that the soil As concentration was significantly reduced not only for easily extractable As, but also for relatively strongly bound forms of As. Enclosing the magnetite in a dialysis bag substantially limited the As mass transfer from soil to magnetite. These results suggest that improving the mixture between Fe oxides and soils can facilitate the effectiveness of As stabilization using Fe oxides.
authors.affiliation: Division of Public Infrastructure Assessment, Environmental Assessment Group, Korea Environmental Institute, 370 Sicheong-daero, Sejong, 30147, Republic of Korea.
authors.forename: Kyung
authors.initials: K
authors.lastname: Yang
authors.affiliation: Department of Civil and Environmental Engineering, College of Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
authors.forename: Byung-Chul
authors.initials: BC
authors.lastname: Kim
authors.affiliation: Department of Civil and Environmental Engineering, College of Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
authors.forename: Kyoungphile
authors.initials: K
authors.lastname: Nam
authors.affiliation: Department of Civil and Environmental Engineering, College of Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea. ychoi81@snu.ac.kr.
authors.forename: Yongju
authors.initials: Y
authors.lastname: Choi
mesh_terms: D001151:Arsenic; D052203:Ferrosoferric Oxide; D010087:Oxides; D012987:Soil; D012989:Soil Pollutants
chemical_list: D010087:Oxides; D012987:Soil; D012989:Soil Pollutants; D001151:Arsenic; D052203:Ferrosoferric Oxide
keywords: Arsenic; Chemical form; Kinetics; Magnetite; Mass transfer; Soil