Synthesis and characterization of hydrotalcites: [Zn{sub 1{minus}x}Al{sub x}(OH){sub 2}](CO{sub 3}){sub x/2{center_dot}}mH{sub 2}O; x = 0.25--0.66
- Inst. Politecnico Nacional, Mexico City (Mexico)
- Inst. Mexicano del Petroleo, Mexico City (Mexico)
In this work a series of [Zn{sub 1{minus}x}Al{sub x}(OH){sub 2}](CO{sub 3}){sub x/2{center_dot}}mH{sub 2}O; x = 0.25--0.66 were prepared at constant pH in order to study the effect of the thermal treatment on their crystalline structure. It was found that it is possible to obtain pure Zn-Al hydrotalcite materials within a x = 0.25--0.50 range in comparison with Mg-Al hydrotalcites which yield pure phases in more restricted x ranges (0.25--0.33). All Zn-Al hydrotalcites lost their layered structure at temperatures above 473 K being less stable than their parental Mg-Al hydrotalcite (623 K). Specific surface areas of these materials depended strongly on the Zn/Al ratio and calcination temperature, ranging from 280 to 20 m{sup 2}/g. ZnO and ZnAl{sub 2}O{sub 4} compounds were detected as the calcination products at temperatures higher than 873 K.
- Sponsoring Organization:
- Consejo Nacional de Ciencia y Tecnologia (CONACYT), Mexico City (Mexico)
- OSTI ID:
- 571951
- Report Number(s):
- CONF-961202--; ISBN 1-55899-358-4
- Country of Publication:
- United States
- Language:
- English
Similar Records
Synthesis and surface acid/base properties of magnesium-aluminum mixed oxides obtained from hydrotalcites
Characterization by X-ray absorption, X-ray powder diffraction and magnetic susceptibility of Cu-Zn-Co-Al-containing hydroxycarbonates, oxycarbonates, oxides, and their products of reduction