Aluminum hydroxide solubility in aqueous solutions containing fluoride ions at 50/sup 0/Cype

Journal Article · Wed Jul 01 04:00:00 EDT 1987 · Geochim. Cosmochim. Acta; (United States)

DOI:https://doi.org/10.1016/0016-7037(87)90172-4· OSTI ID:6996658

Sanjuan, B; Michard, G

Aluminum hydroxide solubility experiments were performed at 50/sup 0/C using the method of May et al. (1979b). The shift observed by May at 25/sup 0/C between acidic and alkaline solution was also observed in these experiments. Infrared spectra of solids separated from solutions show that the low solubility values observed in alkaline medium can be related to the formation of a new solid phase: bayerite (or nordstrandite) (pK*/sub S/sub 4// = 13.4 at 50/sup 0/C) in the presence of initial gibbsite. A second set of experiments was performed in solutions containing fluoride ions in the 10/sup -4/-10/sup -3/ M concentration range. Fluorocomplexes are important in acidic solution; Al(OH)/sub m/F/sub p/ mixed complexes can be important in the minimum of Al solubility when total fluoride exceeds 10/sup -3/ M. The authors propose values of thermodynamic data for Al(OH)/sub 2/F/sub 2//sup -/, Al(OH)F/sub 3//sup -/, Al(OH)/sub 2/F/sup 0/ and for aluminum trifluoride solid. The difference of aluminum hydroxide solubility between acidic and alkaline medium is still observed.

• Research Organization: Universite Paris 7 (France)
• OSTI ID: 6996658
• Journal Information: Geochim. Cosmochim. Acta; (United States), Journal Name: Geochim. Cosmochim. Acta; (United States) Vol. 51:7; ISSN GCACA
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580400* -- Geochemistry-- (-1989)
ACID NEUTRALIZING CAPACITY
ALUMINIUM COMPOUNDS
ALUMINIUM HYDROXIDES
CHEMISTRY
DATA
EXPERIMENTAL DATA
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
HYDROGEN COMPOUNDS
HYDROXIDES
INFORMATION
IONIC COMPOSITION
NUMERICAL DATA
OXYGEN COMPOUNDS
PHASE STUDIES
PHYSICAL PROPERTIES
SOLUBILITY
TEMPERATURE EFFECTS
THERMODYNAMIC PROPERTIES
WATER CHEMISTRY