title: Selenium adsorption and speciation with Mg-FeCO₃ layered double hydroxides loaded cellulose fibre.
abstract: A novel adsorbent was developed by coating Mg-FeCO(3) layered double hydroxides (LDHs) on cellulose fibre. The LDHs take up significant amount of selenite and selenate in a wide pH range with similar sorption capacities (pH 3.8-8.0 for selenite and pH 5.8-7.0 for selenate). A mini-column packed with Mg-FeCO(3) LDHs layer coated cellulose fibre particles was incorporated into a sequential injection system for uptake of selenite at pH 6.0. The retained selenite was afterwards collected with 70 μ L of 0.8%(m/v) NaOH as eluent, followed by hydride generation and atomic fluorescence spectrometric detection. Total inorganic selenium was adsorbed at pH 6.0 by the LDHs-cellulose fibre mini-column after selenate was pre-reduced to selenite by 2.0 mol L(-1) HCl at 80°C, and selenium speciation was performed by difference. With a sample volume of 1.0 mL, an enrichment factor of 13.3 was derived with a detection limit of 11 ng L(-1) within a linear range of 0.04-4.0 μg L(-1). A relative standard deviation (RSD) of 3.3% (0.5 μg L(-1), n=11) was achieved. The procedure was validated by analyzing selenium in a certified reference material GBW 10010 (rice), and speciation of inorganic selenium in natural water samples.
authors: Research Center for Analytical Sciences, Northeastern University, Box 332, Shenyang 110819, China. chenml@mail.neu.edu.cn
authors: Ming-Li
authors: ML
authors: Chen
authors: Myog-Il
authors: MI
authors: An
mesh_terms: D000327:Adsorption; D002482:Cellulose / Q000737:chemistry*; D005296:Ferrous Compounds / Q000737:chemistry*; D005618:Fresh Water / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D057230:Limit of Detection; D008274:Magnesium / Q000737:chemistry*; D012015:Reference Standards; D064586:Selenic Acid; D012643:Selenium / Q000032:analysis / Q000737:chemistry*; D018036:Selenium Compounds / Q000032:analysis / Q000737:chemistry*; D012972:Sodium Hydroxide / Q000737:chemistry; D018038:Sodium Selenite / Q000032:analysis / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013054:Spectrophotometry, Atomic; D014867:Water; D014874:Water Pollutants, Chemical / Q000737:chemistry
chemical_list: D005296:Ferrous Compounds; D018036:Selenium Compounds; D014874:Water Pollutants, Chemical; D014867:Water; C005479:magnesium carbonate; D012972:Sodium Hydroxide; D002482:Cellulose; D012643:Selenium; D018038:Sodium Selenite; D064586:Selenic Acid; D008274:Magnesium