Determination of aluminium activity from measurements of fluoride in acid soil solutions
| Autor: | D. N. Munns, M. K. Conyers, K. R. Helyar |
|---|---|
| Rok vydání: | 1992 |
| Předmět: |
chemistry.chemical_classification
Inorganic chemistry chemistry.chemical_element complex mixtures chemistry.chemical_compound chemistry Oxisol Aluminium Alfisol Soil water General Earth and Planetary Sciences General Agricultural and Biological Sciences Clay minerals Inorganic compound Chemical composition Fluoride General Environmental Science |
| Zdroj: | Journal of Soil Science. 43:441-446 |
| ISSN: | 0022-4588 |
| DOI: | 10.1111/j.1365-2389.1992.tb00150.x |
| Popis: | SUMMARY Trivalent aluminium (Al) in solutions extracted Centrifugally from soils with pH ranging from 3.3 to 5.8 in 0.01 M CaCl2 was estimated from: (i) iterative computation using total Al (pyrocatechol violet), pH, major ions and Al ligands (PCV + GEOCHEM); (ii) 15-s reaction with 8-quinolinol (8Q); and (iii) electrode measurements of free and Al-complexed fluoride. Fluoride and hydroxyl complexes were major Al-components. With decreasing pH, complexed and total F increased along with Al, but free F decreased. Results from PCV + GEOCHEM and 8Q were consistent with each other and with solubilities of the clay minerals in the soils. Relative to these, the F-electrode method increasingly overestimated Al as pH increased and Al decreased; its evident failure was not attributable to La interference, OH interference, or the uncertainty of electrode calibration at F activities below 10−6 M. |
| Databáze: | OpenAIRE |
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