A mutual separation process that uses rare‐earth oxychloride in a proactive way was developed. In particular, the heat‐treatment conditions under which DyCl₃ is converted into DyOCl (without causing such conversion of NdCl₃) in dry oxygen with 6.5 ppm of H₂O (dew point: 209 K) at a relatively low temperature (around 573 K) were determined. A difference between conversion reactions of the two kinds of rare‐earth chlorides into rare‐earth oxychlorides appeared in the case of an oxygen atmosphere with ultra‐low H₂O content, although this difference is usually hidden in the presence of atmospheric humidity. Under these conditions, high separability of a NdCl₃ and DyCl₃ mixture was demonstrated.

中文翻译：

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稀土氯化物转化为氯氧化物转化反应的隐藏性质及其在新型分离中的应用

开发了一种相互分离的方法，该方法以积极的方式使用稀土氧氯化物。特别是在相对较低的温度（约573℃）下，在含有6.5 ppm H ₂ O（露点：209 K）的干氧中，将DyCl ₃转化为DyOCl（不引起NdCl ₃转化）的热处理条件。K）被确定。在H ₂ O含量超低的氧气气氛中，两种稀土氯化物转化成稀土氯氧化物的反应之间存在差异，尽管这种差异通常隐藏在大气湿度下。在这些条件下，NdCl ₃和DyCl _3的高分离性 证明了混合物。