Thermal decomposition of hydrotalcite with chromate, molybdate or sulphate in the interlayer

被引：44

作者：

Frost, RL ^{[1
]}

Musumeci, AW ^{[1
]}

Bostrom, T ^{[1
]}

Adebajo, MO ^{[1
]}

Weier, ML ^{[1
]}

Martens, W ^{[1
]}

机构：

[1] Queensland Univ Technol, Sch Phys & Chem Sci, Inorgan Mat Res Program, Brisbane, Qld 4001, Australia

来源：

THERMOCHIMICA ACTA | 2005年 / 429卷 / 02期

基金：

澳大利亚研究理事会;

关键词：

hydrotalcite; Takovite; pyroaurite; chromate; molybdate; thermal analysis; thermograximetry;

D O I：

10.1016/j.tca.2005.03.014

中图分类号：

O414.1 [热力学];

学科分类号：

摘要：

The thermal decomposition of hydrotalcites with chromate, molybdate and sulphate in the interlayer has been studied using thermogravimetric analysis coupled to a mass spectrometer measuring the gas evolution. X-ray diffraction shows the hydrotalcites have a d(0 0 3) spacing of 7.98 angstrom with very small differences in the d-spacing between the three hydrotalcites. XRD was also used to determine the products of the thermal decomposition. For the sulphate-hydrotalcite decomposition the products were MgO and a spinet MgAl2O4, for the chromate interlayered hydrotalcite MgO, Cr2O3 and spinel. For the molybdate interlayered hydrotalcite the products were MgO, spinet and MgMoO4. EDX analyses enabled the formula of the hydrotalcites to be determined. Two processes are observed in the thermal decomposition namely dehydration and dehydroxylation and for the case of the sulphate interlayered hydrotalcite, a third process is the loss of sulphate. Both the dehydration and dehydroxylation take place in three steps each for each of the hydrotalcites. (c) 2005 Elsevier B.V. All rights reserved.

引用

页码：179 / 187

页数：9

共 11 条

[1] Slow transformation of mechanically dehydroxylated kaolinite to kaolinite -: an aged mechanochemically activated formamide-intercalated kaolinite study [J].