Microwave-Assisted Hydrothermal Synthesis of Ni-Mg Layered Silicate Clays
Résumé
The synthesis of Ni-containing layered silicate clays from the lizardite-nepouite series (1:1) and kerolite-pimelite series (2:1) with random distribution of octahedral cations was feasible with the microwave-assisted hydrothermal synthesis method. These series were obtained from co-precipitated gels with Si 2 Mg 3-x Ni x O 7 .nH 2 O and Si 4 Mg 3-x Ni x O 11 .nH 2 O (x = 0, 0.5, 1, 1.5, 2, 2.5, and 3) compositions. Syntheses were performed at 220°C during 48 hours under equilibrium water pressure using microwave furnace. X-ray diffraction revealed pure 1:1 and 2:1 synthesized phyllosilicates for the lizardite and the kerolite series, respectively.
Fourier transform infrared spectroscopy in both near and mid infrared regions revealed a random distribution of Ni cations in the octahedral sheet of 1:1 and 2:1 silicate clays, that is a good requirement for material applications, especially for the synthesis of metallic catalysts.