Abstract
AbstractDouble hydroxide solids precipitated homogeneously from three laboratory-synthesized aqueous solutions that simulated mildly contaminated surface or groundwater. Over a limited pH range, precipitates formed rapidly from dissolved ions, and more slowly by incorporating ions dissolving from other solids, including highly soluble aluminous solids. The precipitates were characterized by size and shape via transmission electron microscopy (TEM), by composition via inductively coupled plasma-mass spectrometry (ICP-MS) of mother solutions and analytical electron microscopy (AEM) of precipitates, and by structure via powder X-ray diffraction (XRD), TEM, and extended X-ray absorption fine structure (EXAFS) spectroscopy. They were identified as nanocrystalline cobalt hydrotalcite (CoHT) of the form [Co(II)1-xAl(III)x(OH)2]x+(An−x/n)·mH2O, with x = 0.17–0.25, A = CO32−, NO3−, or H3SiO4−n = anion charge and m undetermined. Complete solid solution may exist at the macroscopic level for the range of stoichiometrics reported, but clustering of Co atoms within hydroxide layers indicates a degree of immiscibility at the molecular scale. Composition evolved toward the Co-rich endmember with time for at least one precipitate. The small layer charge in the x = 0.17 precipitate caused anionic interlayers to be incomplete, producing interstratification of hydrotalcite and brucite-like layers. Solubility products estimated from solution measurements for the observed final CoHT stoichiometries suggest that CoHT is less soluble than the inactive forms of Co(OH)2 and CoCO3 near neutral pH. Low solubility and rapid formation suggest that CoHT solids may be important sinks for Co in contact with near neutral pH waters. Because hydrotalcite can incorporate a range of transition metals, precipitation of hydrotalcite may be similarly effective for removing other trace metals from natural waters.
References
50
Referenced
52
10.3406/bulmi.1980.7392
10.2138/am-1997-5-607
10.1016/S0016-7037(99)00125-8
{'volume-title': 'Geochemical Thermodynamics', 'year': '1994', 'author': 'Nordstrom', 'key': 'S0009860400021686_CR29'}
/ Geochemical Thermodynamics by Nordstrom (1994){'volume-title': 'The Hydrolysis of Cations', 'year': '1986', 'author': 'Baes', 'key': 'S0009860400021686_CR4'}
/ The Hydrolysis of Cations by Baes (1986){'key': 'S0009860400021686_CR14', 'first-page': '273', 'volume-title': 'Scientific Basis for Nuclear Waste Management, Volume 50', 'author': 'Crovisier', 'year': '1986'}
/ Scientific Basis for Nuclear Waste Management, Volume 50 by Crovisier (1986)10.1346/CCMN.1983.0310409
{'volume-title': 'HYDRAQL: A program for the computation of chemical equilibrium composition of aqueous batch systems including surface-complexation modeling of ion adsorption at the oxide/solution interface', 'year': '1988', 'author': 'Papelis', 'key': 'S0009860400021686_CR30'}
/ HYDRAQL: A program for the computation of chemical equilibrium composition of aqueous batch systems including surface-complexation modeling of ion adsorption at the oxide/solution interface by Papelis (1988)10.1016/0920-5861(91)80068-K
{'volume-title': 'Dynamic ion partitioning among dissolved, adsorbed, and precipitated phases in aging cobalt(II)/kaolinite/water systems', 'year': '1998', 'author': 'Thompson', 'key': 'S0009860400021686_CR44'}
/ Dynamic ion partitioning among dissolved, adsorbed, and precipitated phases in aging cobalt(II)/kaolinite/water systems by Thompson (1998)10.1016/0378-7753(94)02023-X
{'volume-title': 'EXAFSPAK: A suite of computer programs for analysis of x-ray absorption spectra', 'year': '1995', 'author': 'George', 'key': 'S0009860400021686_CR18'}
/ EXAFSPAK: A suite of computer programs for analysis of x-ray absorption spectra by George (1995)10.1017/CBO9781139173650
{'key': 'S0009860400021686_CR10', 'first-page': '836', 'article-title': 'A crystal-chemical study of Mg,Al and Ni,Al hydroxy-perchlorates and hy-droxy-carbonates', 'volume': '64', 'author': 'Brindley', 'year': '1979', 'journal-title': 'American Mineralogist'}
/ American Mineralogist / A crystal-chemical study of Mg,Al and Ni,Al hydroxy-perchlorates and hy-droxy-carbonates by Brindley (1979)10.2136/sssaj1996.03615995006000060022x
10.1021/ja00014a001
10.1006/jcis.1996.4624
{'key': 'S0009860400021686_CR28', 'first-page': '39', 'volume-title': 'The Environmental Chemistry of Aluminum', 'author': 'Nordstrom', 'year': '1996'}
/ The Environmental Chemistry of Aluminum by Nordstrom (1996)10.1021/cm980523u
10.1016/0022-4596(87)90323-9
- Allmann, R. and Jepsen, H.R. , 1969 Die struktur des hydrotalkits Neues Jahrbuch für Mineralogie Monatshefte 544–551.
10.1016/0021-9797(85)90400-X
10.1016/0016-7037(91)90127-Q
10.1006/jcis.1996.4539
10.1006/jssc.1994.1340
10.1021/es960498y
10.1021/j150645a008
10.1021/cm980524m
10.1016/S0016-7037(98)00136-7
10.18174/njas.v35i3.16720
10.1524/zkri.1936.93.1.368
{'volume-title': 'N1ST Critical Stability Constants of Metal Complexes Database', 'year': '1997', 'author': 'Smith', 'key': 'S0009860400021686_CR41'}
/ N1ST Critical Stability Constants of Metal Complexes Database by Smith (1997)10.1346/CCMN.1997.0450604
{'volume-title': 'Mechanisms of fixation of the trace metals manganese and nickel by ferric hydroxide', 'year': '1973', 'author': 'Subramanian', 'key': 'S0009860400021686_CR42'}
/ Mechanisms of fixation of the trace metals manganese and nickel by ferric hydroxide by Subramanian (1973)10.1016/0254-0584(92)90258-A
10.1021/cm00050a017
10.1180/claymin.1984.019.4.06
10.1107/S0567740869003220
{'key': 'S0009860400021686_CR2', 'first-page': '99', 'article-title': 'Doppelschichtstrukturen mit brucitahnlichen schichtionen [Me(II)1-xMe(III)x(OH)2]x+', 'volume': '24', 'author': 'Allmann', 'year': '1970', 'journal-title': 'Chimia'}
/ Chimia / Doppelschichtstrukturen mit brucitahnlichen schichtionen [Me(II)1-xMe(III)x(OH)2]x+ by Allmann (1970)10.1002/hlca.19420250314
10.1016/0022-3115(92)90096-4
10.1021/ja00151a010
10.1126/science.278.5340.1106
10.1016/0021-9517(85)90219-2
10.1180/claymin.1997.032.4.10
10.1107/S0365110X65003493
{'key': 'S0009860400021686_CR22', 'first-page': '81', 'volume-title': 'The Environmental Chemistry of Aluminum', 'author': 'Hemingway', 'year': '1996'}
/ The Environmental Chemistry of Aluminum by Hemingway (1996){'volume-title': 'Handbook of Thermodynamic Data', 'year': '1974', 'author': 'Naumov', 'key': 'S0009860400021686_CR26'}
/ Handbook of Thermodynamic Data by Naumov (1974)10.1016/S0009-2541(98)00085-0
10.1107/S0567740868003511
Dates
Type | When |
---|---|
Created | 19 years ago (Aug. 23, 2006, 3:40 a.m.) |
Deposited | 2 weeks, 3 days ago (Aug. 20, 2025, 1:33 a.m.) |
Indexed | 2 weeks, 2 days ago (Aug. 21, 2025, 2:13 p.m.) |
Issued | 26 years, 1 month ago (Aug. 1, 1999) |
Published | 26 years, 1 month ago (Aug. 1, 1999) |
Published Online | 1 year, 6 months ago (Feb. 28, 2024) |
Published Print | 26 years, 1 month ago (Aug. 1, 1999) |
@article{Thompson_1999, title={Ambient-Temperature Synthesis, Evolution, and Characterization of Cobalt-Aluminum Hydrotalcite-Like Solids}, volume={47}, ISSN={1552-8367}, url={http://dx.doi.org/10.1346/ccmn.1999.0470405}, DOI={10.1346/ccmn.1999.0470405}, number={4}, journal={Clays and Clay Minerals}, publisher={Cambridge University Press (CUP)}, author={Thompson, Hillary A. and Parks, George A. and Brown, Gordon E.}, year={1999}, month=aug, pages={425–438} }