Determination and reduction of Fe(III) incorporated into Mg–Fe layered double hydroxide structures

The syntheses of Mg–Fe(III) layered double hydroxides with different compositions at varied temperature through a co-precipitation method were attempted. The well-crystallized and white colored layered double hydroxides with chloride anions were obtained from the samples adjusted to the composition of Mg/Fe=4 and aged at higher temperature. The Fe species in the white colored Mg–Fe layered double hydroxides were evaluated as all Fe(III) species by a Mössbauer measurement. The synthesized Mg–Fe(III) layered double hydroxide was treated with a sugar alcohol at temperature above its melting point in order to reduce Fe(III) incorporated into the hydroxide layers. The Mg–Fe layered double hydroxide resulting from a sugar alcohol treatment showed the reduction property in an aqueous solution. The white colored Mg–Fe layered double hydroxide powder turned into a greenish white in a color after the treatment with sugar alcohol at 180°C for 1h. The reduced Mg–Fe layered double hydroxide showed the reduction property in an aqueous solution. [Display omitted] •White colored Mg–Fe layered double hydroxides with chloride anions were synthesized.•Mg–Fe layered double hydroxide was reduced through a melted sugar alcohol treatment.•Mg–Fe layered double hydroxides can be utilized as reusable adsorbents and reductants.