title: Functionalized mesoporous silicas with crown ether moieties for selective adsorption of lithium ions in artificial sea water.
abstract: Lithium ion has been increasingly recognized in a wide range of industrial applications. In this work, we studied on the adsorption of Li+ in the artificial seawater with high selectivity using methyl-crown ether (AC-SBA-15) and aza-crown ether (HMC-SBA-15) moieties-functionalized mesoporous silica materials. First, methyl-crown ether and aza-crown ether moieties-functionalized mesoporous silica materials were synthesized via two-step post-synthesis process using a grafting method. The functionalized materials were employed to the metal ion adsorption from aqueous solution (artificial seawater) containing Li+, Co2+, Cr3+ and Hg2+. The prepared hybrid material showed high selectivity for Li+ ion in the artificial seawater at pH 8.0. The absorbed amount of Li+ was 73 times higher than Cr3+ for aza-crown ether containing AC-SBA-15 as an absorbent. The absorbed amount of Co2+ (4.5 x 10(-5) mol/g), Cr3+ (1.5 x 10(-5) mol/g) and Hg2+ (2.25 x 10(-4) mol/g) were remarkably lower than the case of Li+. On the other hand, the absorbed amount of various metal ions of HMC-SBA-15 with amine groups in alky chains and crown ether moieties were 1.1 x 10(-3) mol/g for Li+, 5.0 x 10(-5) mol/g for Co2+, 2.9 x 10(-4) mol/g for Cr3+, 2.8 x 10(-4) mol/g for Hg2+ mol/g, respectively.
authors.forename: Soo Park
authors.initials: SP
authors.lastname: Sung
authors.forename: Madhappan Santha
authors.initials: MS
authors.lastname: Moorthy
authors.forename: Hyun-Jin
authors.initials: HJ
authors.lastname: Song
authors.forename: Chang-Sik
authors.initials: CS
authors.lastname: Ha
mesh_terms: D000327:Adsorption; D043844:Crown Ethers / Q000737:chemistry*; D008094:Lithium / Q000737:chemistry*; D019216:Metals, Heavy / Q000032:analysis / Q000737:chemistry; D008956:Models, Chemical; D012623:Seawater / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry
chemical_list: D043844:Crown Ethers; D019216:Metals, Heavy; D014874:Water Pollutants, Chemical; D012822:Silicon Dioxide; D008094:Lithium