Iron solubility related to particle sulfur content in source emission and ambient fine particles.
Iron solubility related to particle sulfur content in source emission and ambient fine particles.
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DOI：
10.1021/es300701c
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发表时间：
2012-06
影响因子：
11.4
通讯作者：
M. Oakes;E. Ingall;Barry Lai;Martin M. Shafer;Michael D. Hays;Zhen Liu;Armistead G. Russell;Rodney J. Weber
中科院分区：
文献类型：
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作者：
M. Oakes;E. Ingall;Barry Lai;Martin M. Shafer;Michael D. Hays;Zhen Liu;Armistead G. Russell;Rodney J. Weber
在源排放(如生物质燃烧、煤飞灰、矿物粉尘和汽车尾气)和环境(佐治亚州亚特兰大)细颗粒物(PM2.5)中，研究了影响铁溶解度(可溶性铁/总铁)的化学因素。用X射线吸收近边结构(XANES)光谱和显微X射线荧光光谱表征了含铁颗粒的化学性质(形态和混合状态)。通过浸出实验对样品的全铁溶解度(可溶性铁/总铁)进行了量化。源排放样品中铁的溶解度差异很大，从低溶解度(1%，矿物粉尘和煤飞灰)到75%(汽车尾气和生物质燃烧排放)不等。铁的溶解度差异与硅含量或Fe(II)含量无关。然而，源排放和环境样品的高铁溶解度对应于在单个颗粒物中观察到的硫含量。亚特兰大PM2.5细小颗粒物(N=358)的一系列样品中大量铁的溶解度和大量硫酸盐含量之间的类似对应关系进一步支持了这一趋势。此外，线性组合拟合实验结果表明，在几个高铁溶度源排放和环境PM2.5样品中都存在硫酸铁。这些结果表明，含铁颗粒的硫酸盐含量(与硫酸铁的存在和/或H(2)SO(4)的酸处理机理有关)是铁溶解度的重要指标。
The chemical factors influencing iron solubility (soluble iron/total iron) were investigated in source emission (e.g., biomass burning, coal fly ash, mineral dust, and mobile exhaust) and ambient (Atlanta, GA) fine particles (PM2.5). Chemical properties (speciation and mixing state) of iron-containing particles were characterized using X-ray absorption near edge structure (XANES) spectroscopy and micro-X-ray fluorescence measurements. Bulk iron solubility (soluble iron/total iron) of the samples was quantified by leaching experiments. Major differences were observed in iron solubility in source emission samples, ranging from low solubility (<1%, mineral dust and coal fly ash) up to 75% (mobile exhaust and biomass burning emissions). Differences in iron solubility did not correspond to silicon content or Fe(II) content. However, source emission and ambient samples with high iron solubility corresponded to the sulfur content observed in single particles. A similar correspondence between bulk iron solubility and bulk sulfate content in a series of Atlanta PM2.5 fine particle samples (N = 358) further supported this trend. In addition, results of linear combination fitting experiments show the presence of iron sulfates in several high iron solubility source emission and ambient PM2.5 samples. These results suggest that the sulfate content (related to the presence of iron sulfates and/or acid-processing mechanisms by H(2)SO(4)) of iron-containing particles is an important proxy for iron solubility.