Hydrotalcite-like minerals (&lt;em&gt;M&lt;/em&gt;&lt;sub&gt;2&lt;/sub&gt;Al(OH)&lt;sub&gt;6&lt;/sub&gt;(CO&lt;sub&gt;3&lt;/sub&gt;)&lt;sub&gt;0.5&lt;/sub&gt;.&lt;em&gt;X&lt;/em&gt;H&lt;sub&gt;2&lt;/sub&gt;O, where &lt;em&gt;M&lt;/em&gt; = Mg, Zn, Co, Ni) in the environment: synthesis, characterization and thermodynamic stability

Johnson, C.A.; Glasser, F.P.

doi:10.1346/CCMN.2003.510101

Hydrotalcite-like minerals (M₂Al(OH)₆(CO₃)_0.5.XH₂O, where M = Mg, Zn, Co, Ni) in the environment: synthesis, characterization and thermodynamic stability

Johnson CA & Glasser FP

Citation

Johnson, C. A., & Glasser, F. P. (2003). Hydrotalcite-like minerals (M₂Al(OH)₆(CO₃)_0.5.XH₂O, where M = Mg, Zn, Co, Ni) in the environment: synthesis, characterization and thermodynamic stability. Clays and Clay Minerals, 51(1), 1-8. https://doi.org/10.1346/CCMN.2003.510101

Persistent URL https://www.dora.lib4ri.ch/eawag/islandora/object/eawag:4603

Hydrotalcite-like layered double hydroxides (LDH), of the formulation M₂Al(OH)₆(CO₃)_0.5.H₂O, where M = Mg, Zn, Co, Ni, have been prepared, the products characterized and their solubility products measured at ionic strengths of 0.0065 and 0.0128 M and at 25°C. Steady-state solubility was reached after 100 days. The solubility products have been formulated according to the following reaction: M₂Al(OH)₆0.5CO₃·H₂O +6H⁺ → 2M²⁺ + Al³⁺ + 0.5CO₃^2- + H₂O where [a formula is given for the solubility product K_SO] Average values of K_SO for I = 0, estimated using the Davies equation, are 25.43, 20.80, 22.88 and 20.03 for Mg, Zn, Co and Ni, respectively. Model calculations reveal that the thermodynamic stability of the LDHs is greater than that of the corresponding divalent hydroxides for Zn, Co and Ni below a pH of ~10, 9 and 8, respectively, and at least up to pH 12 for Mg.

Details

Publication Type

Journal Article

Title

Hydrotalcite-like minerals (M₂Al(OH)₆(CO₃)_0.5.XH₂O, where M = Mg, Zn, Co, Ni) in the environment: synthesis, characterization and thermodynamic stability

Author(s)

Johnson, C.A. (Eawag)

Glasser, F.P.

Journal

Clays and Clay Minerals

Volume

Issue

Start Page

End Page

Publication Year

2003

Peer Review

Yes

Keywords

cobalt
hydrotalcite
magnesium
nickel
solubility
zinc

Hydrotalcite-like minerals (M2Al(OH)6(CO3)0.5.XH2O, where M = Mg, Zn, Co, Ni) in the environment: synthesis, characterization and thermodynamic stability

Hydrotalcite-like minerals (M₂Al(OH)₆(CO₃)_0.5.XH₂O, where M = Mg, Zn, Co, Ni) in the environment: synthesis, characterization and thermodynamic stability