Sorption of Eu(III) on attapulgite studied by batch, XPS, and EXAFS techniques
| Autor: | Gilles Montavon, Jiaxing Li, Wangsuo Wu, Xiangke Wang, Xiaoli Tan, Q. H. Fan |
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| Rok vydání: | 2009 |
| Předmět: |
Inorganic chemistry
Molecular Conformation Magnesium Compounds 02 engineering and technology 010403 inorganic & nuclear chemistry 01 natural sciences Adsorption X-ray photoelectron spectroscopy Europium medicine Environmental Chemistry Humic acid Benzopyrans Humic Substances chemistry.chemical_classification Ions Extended X-ray absorption fine structure Fourier Analysis Chemistry Silicon Compounds Temperature Palygorskite Spectrometry X-Ray Emission Sorption General Chemistry Hydrogen-Ion Concentration 021001 nanoscience & nanotechnology 0104 chemical sciences Ionic strength Absorption (chemistry) 0210 nano-technology Algorithms Nuclear chemistry medicine.drug Environmental Monitoring |
| Zdroj: | Environmental sciencetechnology. 43(15) |
| ISSN: | 0013-936X |
| Popis: | The effects of pH, ionic strength, and temperature on sorption of Eu(III) on attapulgite were investigated in the presence and absence of fulvic acid (FA) and humic acid (HA). The results indicated that the sorption of Eu(III) on attapulgite was strongly dependent on pH and ionic strength, and independent of temperature. In the presence of FA/HA, Eu(III) sorption was enhanced at pH4, decreased at pH range of 4-6, and then increased again at pH7. The X-ray photoelectron spectroscopy (XPS) analysis suggested that the sorption of Eu(III) might be expressed as is identical to X3Eu0, is identical to S(w)OHEu3+, and is identical to SOEu-OOC-/HA in the ternary Eu/HN/attapulgite system. The extended X-ray absorption fine structure (EXAFS) analysis of Eu-HA complexes indicated that the distances of d(Eu-O) decreased from 2.415 to 2.360 angstroms with increasing pH from 1.76 to 9.50, whereas the coordination number (N) decreased from approximately 9.94 to approximately 8.56. Different complexation species were also found for the different addition sequences of HA and Eu(III) to attapulgite suspension. The results are important to understand the influence of humic substances on Eu(III) behavior in the natural environment. |
| Databáze: | OpenAIRE |
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