title: Heavy metal stabilization in contaminated soil by treatment with calcined cockle shell.
abstract: In several previous studies, the efficacy of various liming waste materials on the immobilization of heavy metals has been tested and it was found that soils contaminated with heavy metals can be stabilized using this technique. Since lime (CaO) has been identified as the main phase of calcined cockle shell (CCS), it was hypothesized that CCS could be used as a soil amendment to immobilize heavy metals in soil. However, to date, no studies have been conducted using CCS. In this study, the effectiveness of CCS powder on the immobilization of Cd, Pb, and Zn in mine tailing soil was evaluated. After 28 days of incubation, the treated soil samples were exposed to weathering (four cycles of freezing-thawing and four cycles of wetting-drying) for 8 days before being subjected to a leaching test. The results of this study revealed that the soil pH increased from 7.5 to 12.2 with the addition of 5% CCS. A similar soil pH was obtained when the soil was amended with 5% pure CaO. By leaching with 0.1 M HCl, extracted Cd, Pb, and Zn were reduced by up to 85, 85, and 91%, respectively. Therefore, CCS is suggested as a low-cost lime-based soil amendment for stabilizing heavy metals in abandoned mining sites.
authors.affiliation: Department of Environment and Energy Engineering, Chonnam National University, Gwangju, 500-757, Republic of Korea.
authors.forename: Mohammad Nazrul
authors.initials: MN
authors.lastname: Islam
authors.affiliation: Department of Environment and Energy Engineering, Chonnam National University, Gwangju, 500-757, Republic of Korea.
authors.forename: Golam
authors.initials: G
authors.lastname: Taki
authors.affiliation: Department of Environment and Energy Engineering, Chonnam National University, Gwangju, 500-757, Republic of Korea.
authors.forename: Xuan Phuc
authors.initials: XP
authors.lastname: Nguyen
authors.affiliation: Department of Environment and Energy Engineering, Chonnam National University, Gwangju, 500-757, Republic of Korea.
authors.forename: Young-Tae
authors.initials: YT
authors.lastname: Jo
authors.affiliation: Department of Environment and Energy Engineering, Chonnam National University, Gwangju, 500-757, Republic of Korea.
authors.forename: Jun
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Environment and Energy Engineering, Chonnam National University, Gwangju, 500-757, Republic of Korea. parkjeo1@jnu.ac.kr.
authors.forename: Jeong-Hun
authors.identifier: http://orcid.org/0000-0002-0661-0059
authors.initials: JH
authors.lastname: Park
mesh_terms: D060105:Animal Shells / Q000737:chemistry*; D000818:Animals; D001673:Biodegradation, Environmental; D049873:Cardiidae; D019216:Metals, Heavy / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D019216:Metals, Heavy; D012989:Soil Pollutants
keywords: CaO; Calcined cockle shell (CCS); Contaminated soil; Heavy metals; Immobilization; Soil pH