Characteristics of Oxidation Reaction of Rare-earth Chlorides for Precipitation in LiCl-KCl Molten Salt by Oxygen Sparging
Characteristics of Oxidation Reaction of Rare-earth Chlorides for Precipitation in LiCl-KCl Molten Salt by Oxygen Sparging
复制标题
LiCl-KCl熔盐吹氧沉淀稀土氯化物的氧化反应特性
DOI：
10.1080/18811248.2006.9711221
复制
发表时间：
2006
影响因子：
1.2
通讯作者：
Intae Kim
中科院分区：
文献类型：
--
作者：
Y. Cho;H. Yang;H. Eun;Eung;Intae Kim
用喷氧法研究了某些稀土氯化物(La/Ce/Nd/GdCl3)在LiCl-KCl熔盐中的沉淀反应。在本研究中，无论喷氧时间和熔盐温度如何，LaCl3、NdCl3和GdCl3的氯氧化合物(REOCl)和CeCl3的氧化物(REO2)都是沉淀。用转化率描述了稀土氯化物转化为难溶沉淀物的过程。转化率随喷氧时间呈指数增加，在1023K的熔盐温度条件下出现渐近值。LaCl3、NdCl3和GdCl3的转化率随着熔盐温度的升高而增加，但在熔盐温度从823K升高到923K、60min时，转化率从0.660增加到0.995，CeCl3的转化率随着熔盐温度的升高几乎保持不变(超过0.999)。对沉淀物(氧氯化物)的热重分析表明，LaOCl、NdOCl和GdOCl的失重率约为11%-13%，在高温和氧气气氛中，所有的氧氯化物都转化为它们的氧化物，即La_2O_3、Nd_2O_3和Gd_2O_3。
The precipitation reaction of some rare earth chlorides (La/Ce/Nd/GdCl3) in a LiCl-KCl molten salt has been carried out by using the oxygen sparging method. In this study, regardless of the oxygen sparging time and the molten salt temperature, oxychlorides (REOCl) for LaCl3, NdCl3 and GdCl3, and an oxide (REO2) for CeCl3 are formed as a precipitate. The conversion of rare-earth chlorides into insoluble precipitates was described by using a conversion ratio. The conversion ratio increased exponentially with the oxygen sparging time and finally showed asymptotic value at 1,023 K of the molten salt temperature condition. The conversion ratios of LaCl3, NdCl3 and GdCl3 were increased with the molten salt temperature, however, even though the conversion ratio was increased from 0.660 to 0.995 with increasing molten salt temperature from 823 to 923 K at 60 min of a sparging time, the values of the conversion ratio of CeCl3 were nearly constant (over 0.999) with the molten salt temperature. As a result of the thermogravimetric analysis of the precipitates (oxychlorides), about 11–13% of a weight loss happened in the case of LaOCl, NdOCl and GdOCl, and all the oxychlorides were converted to their oxides i.e. La2O3, Nd2O3 and Gd2O3 at a high temperature and oxygen atmosphere.