%0 Journal Article
%T Synthesis and Characterization of Methanesulfonate and Ethanesulfonate Intercalated Lithium Aluminum LDHs
%A Anton Niksch
%A Herbert P£¿llmann
%J Natural Resources
%P 59-71
%@ 2158-7086
%D 2021
%I Scientific Research Publishing
%R 10.4236/nr.2021.123006
%X <span style=\"font-family:Verdana;\"> <span style=\"font-family:;\" \"=\"\">LDH-phases become increasingly interesting due to their broad ability to
be able to incorporate many different cat</span><span style=\"font-family:;\" \"=\"\">ions</span><span style=\"font-family:;\" \"=\"\"> and anions. The intercalation of methanesulfonate
and ethanesulfonate into a Li-LDH as well as the behavior of the interlayer
structure as a function of the temperature is presented. A hexagonal P6<sub>3</sub>/m
[LiAl<sub>2</sub>(OH)<sub>6</sub>][Cl?1</span><span style=\"font-family:;\" \"=\"\">.</span><span style=\"font-family:;\" \"=\"\">5H<sub>2</sub>O] (Li-Al-Cl) precursor LDH was
synthesized by hydrothermal treating of a LiCl solution with <i>¦Ã</i>-Al(OH)<sub>3</sub>. This precursor was
used to intercalate methanesulfonate (CH<sub>3</sub>O<sub>3</sub>S<sup>?</sup>)
and ethanesulfonate (C<sub>2</sub>H<sub>5</sub>O<sub>3</sub>S<sup>?</sup>)
through anion exchange by stirring Li-Al-Cl in a solution of the respective
organic Li-salt (90?C, 12 h). X-ray diffraction pattern showed an
increase of the interlayer space <i>c</i></span><i><span style=\"font-family:;\" \"=\"\">'</span></i><span style=\"font-family:;\" \"=\"\"> (d<sub>001</sub>) of Li-Al-methanesulfonate
(Li-Al-MS) with 1.2886 nm and Li-Al-ethanesulfonate (Li-Al-ES) with 1.3816 nm
compared to the precursor with 0.7630 nm. Further investigations with
Fourier-transform infrared spectroscopy and scanning electron microscopy
confirmed a complete anion exchange of the organic molecules with the precursor
Cl<sup>?</sup>. Both synthesized LDH compounds [LiAl<sub>2</sub>(OH)<sub>6</sub>]CH<sub>3</sub>SO<sub>3</sub>?nH<sub>2</sub>O
(n = 2.24</span><span style=\"font-family:;\" \"=\"\">-</span><span style=\"font-family:;\" \"=\"\">3.72 (Li-Al-MS) and [LiAl<sub>2</sub>(OH)<sub>6</sub>]C<sub>2</sub>H<sub>5</sub>SO<sub>3</sub>}?nH<sub>2</sub>O
(n = 1.5) (Li-Al-ES) showed a monomolecular interlayer structure with
additional interlayer water at room temperature. By increasing the temperature,
the interlayer water was removed and the interlayer space <i>c</i></span><i><span style=\"font-family:;\" \"=\"\">'</span></i><span style=\"font-family:;\" \"=\"\"> of Li-Al-MS decreased to 0.87735 nm (at 55?C).
Calculations showed that a slight displacement of the organic molecules is
necessary to achieve this interlayer space. Different behavior of Li-Al-ES
could be observed during thermal treatment. Two phases coexisted at 75?C </span><span style=\"font-family:;\" \"=\"\">-</span><span style=\"font-family:;\" \"=\"\"> 85?C, one with a
%K LDH
%K Lithium
%K Aliphatic Sulfonic Acid
%K X-Ray Powder Diffraction
%K High Temperature PXRD
%K Layered Double Hydroxides
%K Sulfonate
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=107926