Abstract Distribution of rare earth elements (REEs) in six speciations extracted from coal and coal gangue and their combustion products (slag and fly ash) generated by three different power plants in China were determined by sequential extraction procedure combined with inductively coupled plasma mass spectrometry method. The results show that the REEs mainly occurred as acid soluble and silicate & aluminosilicate fraction, e.g., approximately 42.54% and 45.62% in coal gangue, 32.85% and 57.13% in lignite, and 18.10% and 75.46% in bituminous coal, respectively. However, REEs in the combustion products were mainly presented in silicate & aluminosilicate fraction regardless of coal or coal gangue, reaching up to approximately 80% of the total REEs content. During combustion, around 36%, 23%, and 5% from the other five fractions (water soluble, ion-exchangeable, acid soluble, organic, and sulfide) were transformed to silicate & aluminosilicate fraction from coal gangue, lignite, and bituminous coal, respectively. In the case of coal or coal gangue, the amount of each REEs in the same extracted fraction was different, but the distribution trend of REEs from La to Lu in each fraction was followed in the same rule. In the case of slag and fly ash generated from coal or coal gangue, distribution of REEs from La to Lu in each fraction showed the different trend between fly ash and slag. This was due to the fly ash exposed in flue gas system was much longer than the time for slag formation.

中文翻译：

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煤和煤矸石中稀土元素的存在形式及其燃烧产物

摘要 采用序贯提取程序结合电感耦合等离子体质谱法测定了我国三个不同电厂从煤和煤矸石及其燃烧产物（炉渣和粉煤灰）中提取的六种稀土元素（REEs）的分布情况。 . 结果表明，稀土元素主要以酸溶性和硅酸铝硅酸盐部分的形式存在，煤矸石中约占42.54%和45.62%，褐煤中分别为32.85%和57.13%，烟煤中分别为18.10%和75.46%。然而，无论是煤还是煤矸石，燃烧产物中的 REEs 主要以硅酸盐和铝硅酸盐部分的形式存在，约占 REEs 总含量的 80%。在燃烧过程中，大约 36%、23%、来自其他五种馏分（水溶性、离子交换性、酸溶性、有机物和硫化物）的 5% 分别从煤矸石、褐煤和烟煤中转化为硅酸盐和铝硅酸盐。在煤或煤矸石的情况下，同一提取馏分中各稀土元素的含量不同，但各馏分中稀土元素从La到Lu的分布趋势遵循相同的规律。以煤或煤矸石产生的矿渣和飞灰为例，各馏分中稀土元素从La到Lu的分布表现出飞灰和矿渣之间的不同趋势。这是由于飞灰暴露在烟气系统中的时间远长于成渣的时间。和烟煤，分别。在煤或煤矸石的情况下，同一提取馏分中各稀土元素的含量不同，但各馏分中稀土元素从La到Lu的分布趋势遵循相同的规律。以煤或煤矸石产生的矿渣和飞灰为例，各馏分中稀土元素从La到Lu的分布表现出飞灰和矿渣之间的不同趋势。这是由于飞灰暴露在烟气系统中的时间远长于成渣的时间。和烟煤，分别。在煤或煤矸石的情况下，同一提取馏分中各稀土元素的含量不同，但各馏分中稀土元素从La到Lu的分布趋势遵循相同的规律。以煤或煤矸石产生的矿渣和飞灰为例，各馏分中稀土元素从La到Lu的分布表现出飞灰和矿渣之间的不同趋势。这是由于飞灰暴露在烟气系统中的时间远长于成渣的时间。各馏分中从拉到鲁的稀土元素分布表现出飞灰和渣之间的不同趋势。这是由于飞灰暴露在烟气系统中的时间远长于成渣的时间。各馏分中从拉到鲁的稀土元素分布表现出飞灰和渣之间的不同趋势。这是由于飞灰暴露在烟气系统中的时间远长于成渣的时间。