REACTION BETWEEN RARE-EARTH-OXIDES AND ELEMENTAL FLUORINE .2. KINETICS OF THE FLUORINATION OF CERIUM DIOXIDE

被引：21
作者：
TAKASHIMA, M
FUKAMI, S
NOSAKA, Y
UNISHI, T
机构：
[1] Faculty of Engineering, Fukui University, Fukui-shi, 910
来源：
JOURNAL OF FLUORINE CHEMISTRY | 1992年 / 57卷 / 1-3期
关键词：
D O I：
10.1016/S0022-1139(00)82824-9
中图分类号：
O61 [无机化学];
学科分类号：
070301 ; 081704 ;
摘要：
The reaction between cerium dioxide and fluorine gas has been studied by means of thermogravimetric, X-ray and magnetic measurements. CeO2 reacts with F2 gas from 130-degrees-C and converts into CeF3 with a characteristic weight decrease above 270-degrees-C. The reaction rate was found to be determined by fluorine gas diffusion described by a modified Jander equation, and the activation energy is estimated to be 80 to 90 kJ/mol. Fluorine is incorporated into the crystal lattice of CeO2 without change of structure or oxidation state of Ce(IV) below 270-degrees-C. To convert into CeF3, the valency Ce(IV) drastically changes to Ce(III) with evolution of oxygen at 270 to 290-degrees-C.
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页码：131 / 138
页数：8
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