Smelting is one of the main sources of rare earth elements (REEs) in large scale smelting regions that have been neglected before. To provide experimental evidence on the influence of smelting processes on REEs in windowsill dust, this study investigated the concentration, chemical fractions, and spatial distribution of 14 REEs in windowsill dust and assessed the possible influence of smelting processes on the geochemical behavior of these REEs. A total of 46 windowsill dust samples were collected from different locations in Baotou, a typical industrial city for large-scale smelting. The fractions of REEs were analyzed by Tessier sequential extraction analysis. The enrichment factor (EF) was adopted to assess the contribution of anthropogenic emissions of REEs. The loess-normalized REE patterns of windowsill dust are similar to those of the iron ore of the Bayan Obo mine, but differ from those of the local soil. The concentrations of La, Ce, Pr, Nd, and ∑REEs in the residual fraction and total digestion decrease gradually with the increase in distance from the smelter in the downwind direction. These results suggested that the accumulation and fractionation of REEs in windowsill dust are considerably influenced by smelting. The emission of smelting is the main source of REEs for windowsill dust in Baotou.

中文翻译：

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包头窗台粉尘中稀土元素的地球化学特征：冶炼行业对含量和成分的影响

在以前被忽略的大规模冶炼区域中，冶炼是稀土元素（REE）的主要来源之一。为了提供熔炼过程对窗台灰尘中稀土元素影响的实验证据，本研究调查了窗台灰尘中14种稀土元素的浓度，化学成分和空间分布，并评估了熔炼过程对这些稀土元素地球化学行为的可能影响。在典型的大规模冶炼工业城市包头，从不同地点收集了总共46个窗台灰尘样品。通过Tessier顺序提取分析法分析REE的分数。采用了富集因子（EF）来评估稀土元素人为排放的贡献。窗台灰尘的黄土归一化稀土元素分布模式与巴彦奥博矿的铁矿石相似，但不同于当地土壤。残留部分和总消化中的La，Ce，Pr，Nd和∑REEs的浓度随着与冶炼厂之间顺风方向距离的增加而逐渐降低。这些结果表明，冶炼对窗台粉尘中稀土元素的积累和分馏有很大的影响。包头窗玻璃粉尘的稀土元素主要来自冶炼。这些结果表明，冶炼对窗台粉尘中稀土元素的积累和分馏有很大的影响。包头窗玻璃粉尘的稀土元素主要来自冶炼。这些结果表明，冶炼对窗台粉尘中稀土元素的积累和分馏有很大的影响。包头窗玻璃粉尘的稀土元素主要来自冶炼。