title: Selective separation of La3+ and lanthanum organic complexes with nanometer-sized titanium dioxide and their detection by using fluorination-assisted electrothermal vaporization ICP-AES with in-situ matrix removal.
abstract: A new method for the determination of free La3+ and La organic complexes in solution using a nanometer-sized titanium dioxide as solid-phase extractant and fluorination-assisted electrothermal vaporization (FETV)-ICP-AES as sensitive detector has been developed. The effect of pH on the adsorption characteristics of La3+ and La complexes of citric acid, 2-hydroxyisobutyric acid (HIBA), and humic acid on nanometer-sized TiO2 was investigated and optimized. On the basis of the difference in volatility between fluoride of analyte (lanthanum) and the fluoride of matrix (titanium), an in-situ removal of the adsorbent matrix (TiO2) from a graphite furnace was realized. Therefore, the free La3+ and adsorbed La complexes on nanometer-sized titanium dioxide could be determined respectively by FETV-ICP-AES without any other chemical pretreatment. The proposed method was applied for the determination of free ion (La3+) and La complexes in synthetic solutions and soil extracts with satisfactory results.
authors.affiliation: Department of Chemistry, Wuhan University, Wuhan 430072, People's Republic of China.
authors.forename: Shengqing
authors.initials: S
authors.lastname: Li
authors.forename: Bin
authors.initials: B
authors.lastname: Hu
authors.forename: Zucheng
authors.initials: Z
authors.lastname: Jiang
authors.forename: Pei
authors.initials: P
authors.lastname: Liang
authors.forename: Xuan
authors.initials: X
authors.lastname: Li
authors.forename: Linbo
authors.initials: L
authors.lastname: Xia
mesh_terms: D000327:Adsorption; D004396:Coloring Agents / Q000737:chemistry*; D004560:Electricity; D004785:Environmental Pollutants / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007811:Lanthanum / Q000302:isolation & purification*; D013696:Temperature; D014025:Titanium / Q000737:chemistry*; D014835:Volatilization
chemical_list: D004396:Coloring Agents; D004785:Environmental Pollutants; C009495:titanium dioxide; D007811:Lanthanum; D014025:Titanium