MORPHOLOGY OF KAOLINITE CRYSTALS SYNTHESIZED UNDER HYDROTHERMAL CONDITIONS

被引：36
作者：
FIORE, S [1 ]
HUERTAS, FJ [1 ]
HUERTAS, F [1 ]
LINARES, J [1 ]
机构：
[1] CSIC,ESTAC EXPTL ZAIDIN,E-18008 GRANADA,SPAIN
来源：
CLAYS AND CLAY MINERALS | 1995年 / 43卷 / 03期
关键词：
CRYSTAL GROWTH; ELECTRON MICROSCOPY; KAOLINITE; LATHS; MORPHOLOGY; PLATES; SPHERULES; SYNTHESIS;
D O I：
10.1346/CCMN.1995.0430310
中图分类号：
O64 [物理化学（理论化学）、化学物理学];
学科分类号：
070304 ; 081704 ;
摘要：
Scanning electron microscopy has revealed the presence of spherical, lath and platy kaolinite in gels with Si/Al atomic ratio ranging from 1.84 to 0.76 that are hydrothermally treated under different temperature and time conditions. Hemispherical structures and excavated zones, at different stages of evolution, have been observed on the surface of the gel grains, indicating that spherical particles do not precipitate from the solution but are generated from the gels. The quantity of spherical particles depends on temperature, time and the chemical composition of the starting gel. Products from starting material with Si/Al approximate to 1 yield the highest quantity of these particles. Being metastable, sphere dissolution controls the chemistry of the solution and consequently the morphology of the precipitating crystals thus producing more elongated, curved and irregular outlines when gels with Si/Al approximate to 1 are hydrothermally treated.
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页码：353 / 360
页数：8
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