title: Water-soluble organo-building blocks of aminoclay as a soil-flushing agent for heavy metal contaminated soil.
abstract: We demonstrated that water-soluble aminopropyl magnesium functionalized phyllosilicate could be used as a soil-flushing agent for heavy metal contaminated soils. Soil flushing has been an attractive means to remediate heavy metal contamination because it is less disruptive to the soil environment after the treatment was performed. However, development of efficient and non-toxic soil-flushing agents is still required. We have synthesized aminoclays with three different central metal ions such as magnesium, aluminum, and ferric ions and investigated applicability of aminoclays as soil flushing agents. Among them, magnesium (Mg)-centered aminoclay showed the smallest size distribution and superior water solubility, up to 100mg/mL. Mg aminoclay exhibited cadmium and lead binding capacity of 26.50 and 91.31 mg/g of Mg clay, respectively, at near neutral pH, but it showed negligible binding affinity to metals in acidic conditions. For soil flushing with Mg clay at neutral pH showed cadmium and lead were efficiently extracted from soils by Mg clay, suggesting strong binding ability of Mg clay with cadmium and lead. As the organic matter and clay compositions increased in the soil, the removal efficiency by Mg clay decreased and the operation time increased.
authors.affiliation: Department of Chemical and Biomolecular Engineering (BK21 program), KAIST, 335 Gwahak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
authors.forename: Young-Chul
authors.initials: YC
authors.lastname: Lee
authors.forename: Eun Jung
authors.initials: EJ
authors.lastname: Kim
authors.forename: Dong Ah
authors.initials: DA
authors.lastname: Ko
authors.forename: Ji-Won
authors.initials: JW
authors.lastname: Yang
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry*; D002712:Chlorides / Q000737:chemistry; D000077215:Clay; D052918:Environmental Restoration and Remediation / Q000379:methods*; D005290:Ferric Compounds / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D015636:Magnesium Chloride / Q000737:chemistry; D019216:Metals, Heavy / Q000032:analysis*; D046529:Microscopy, Electron, Transmission; D016062:Porosity; D033362:Powder Diffraction; D011437:Propylamines; D012821:Silanes / Q000737:chemistry*; D012987:Soil / Q000737:chemistry / Q000592:standards; D012989:Soil Pollutants / Q000032:analysis*; D012995:Solubility; D013499:Surface Properties; D014867:Water / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D000538:Aluminum Silicates; D002712:Chlorides; D005290:Ferric Compounds; D019216:Metals, Heavy; D011437:Propylamines; D012821:Silanes; D012987:Soil; D012989:Soil Pollutants; D015636:Magnesium Chloride; D014867:Water; C477625:amino-propyl-triethoxysilane; D000077215:Clay; C024555:ferric chloride