Solubility of Iron from Combustion Source Particles in Acidic Media Linked to Iron Speciation
Solubility of Iron from Combustion Source Particles in Acidic Media Linked to Iron Speciation
复制标题
酸性介质中燃烧源颗粒中铁的溶解度与铁形态相关
DOI：
10.1021/es302558m
复制
发表时间：
2012-10-16
影响因子：
11.4
通讯作者：
Chen, Jianmin
中科院分区：
文献类型：
--
作者：
Fu, Hongbo;Lin, Jun;Chen, Jianmin
在这项研究中，研究了酸性介质中六种燃烧源颗粒的铁溶解度。为了进行比较，还包括中国黄土（CL）粉尘。溶解度实验证实铁的溶解度变化很大并且取决于颗粒来源。在黑暗和光照条件下，燃烧源颗粒相对于 CL 溶解得更快、程度更大。与其他样品相比，油飞灰 (FA) 产生最高的可溶性铁。 12 小时后在黑暗中测量的总铁溶解度分数范围为燃烧衍生颗粒初始铁含量的 2.9% 至 74.1%（油 FA > 生物质燃烧颗粒 (BP) > 煤 FA）。在秸秆BP和玉米BP的悬浮液中，二价铁是Fe的主要可溶形式，而在油FA、煤FA和CL的悬浮液中，总溶解Fe主要以三价铁的形式存在。穆斯堡尔测量和 TEM 分析表明，油 FA 中的 Fe 通常呈现为纳米级 Fe3O4 聚集体和富 Fe/S 颗粒。玉米BP中铁的高度不稳定来源可能源自与富钾颗粒内部混合的无定形铁形式。然而，煤 FA 中的 Fe 主要是含铁铝硅酸盐玻璃和铁氧化物的更难溶形式。本文提供的数据表明，铁形态因来源而异，并且是控制酸性溶液中这些人为排放的铁溶解度的重要因素，这表明燃烧衍生颗粒的铁溶解度的变化与气溶胶本身的固有特征和来源有关。这些信息有助于提高我们对燃烧气溶胶在大气传输过程中经历酸性处理时铁溶解度的理解。
In this study, iron solubility from six combustion source particles was investigated in acidic media. For comparison, a Chinese loess (CL) dust was also included. The solubility experiments confirmed that iron solubility was highly variable and dependent on particle sources. Under dark and light conditions, the combustion source particles dissolved faster and to a greater extent relative to CL. Oil fly ash (FA) yielded the highest soluble iron as compared to the other samples. Total iron solubility fractions measured in the dark after 12 h ranged between 2.9 and 74.1% of the initial iron content for the combustion-derived particles (Oil FA > biomass burning particles (BP) > coal FA). Ferrous iron represented the dominant soluble form of Fe in the suspensions of straw BP and corn BP, while total dissolved Fe presented mainly as ferric iron in the cases of oil FA, coal FA, and CL. Mossbauer measurements and TEM analysis revealed that Fe in oil FA was commonly presented as nanosized Fe3O4 aggregates and Fe/S-rich particles. Highly labile source of Fe in corn BP could be originated from amorphous Fe form mixed internally with K-rich particles. However, Fe in coal FA was dominated by the more insoluble forms of both Fe-bearing aluminosilicate glass and Fe oxides. The data presented herein showed that iron speciation varies by source and is an important factor controlling iron solubility from these anthropogenic emissions in acidic solutions, suggesting that the variability of iron solubility from combustion-derived particles is related to the inherent character and origin of the aerosols themselves. Such information can be useful in improving our understanding on iron solubility from combustion aerosols when they undergo acidic processing during atmospheric transport.