State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Thermo Fisher Scientific, Shanghai 200136, China.
Sci Total Environ. 2019 May 10;664:107-115. doi: 10.1016/j.scitotenv.2019.02.001. Epub 2019 Feb 1.
Clarifying the occurrences of organic chemicals in fly ash produced during industrial thermal processes is important for improving our understanding of the formation mechanisms of toxic pollutants such as polycyclic aromatic hydrocarbons (PAHs), halogenated PAHs, dioxins, and other unintentional persistent organic pollutants. We developed a highly sensitive gas chromatography-Orbitrap mass spectrometry (GC-Orbitrap/MS) method and applied it to screening of organic pollutants in fly ash samples from multiple industrial thermal processes. The GC-Orbitrap/MS method could detect and quantify organic pollutants at part per billion (ppb) levels. In total, 96 organic chemicals, including alkanes, benzene derivatives, phenols, polycyclic aromatic hydrocarbons, and biphenyl derivatives were identified in the fly ash samples. Several organic chemicals with chlorine or bromine substituents were abundant in secondary copper smelter fly ash, and these might act as precursors for formation of dioxins, brominated dioxins, and other dioxin-like compounds. Several chlorinated and brominated PAH compounds were also found in the secondary copper smelter fly ash. PAHs were dominant chemicals in the secondary aluminum smelter fly ash samples, and were present in much higher concentrations than in the samples from other industries. This indicates that there are different chemical formation pathways in different industries. Possible formation pathways of PAHs and dioxins were investigated and deduced in this study. These results improve our understanding of the formation mechanisms of toxic unintentional persistent organic pollutants and could be useful for reducing their source emissions.
阐明工业热过程中产生的飞灰中有机化学物质的存在情况，对于提高我们对多环芳烃（PAHs）、卤代 PAHs、二恶英和其他无意持久性有机污染物等有毒污染物形成机制的理解非常重要。我们开发了一种高灵敏度的气相色谱-轨道阱质谱（GC-Orbitrap/MS）方法，并将其应用于多种工业热过程中飞灰样品中有机污染物的筛选。GC-Orbitrap/MS 方法能够以十亿分之一（ppb）的水平检测和定量有机污染物。总共在飞灰样品中鉴定出 96 种有机化学物质，包括烷烃、苯衍生物、酚类、多环芳烃和联苯衍生物。在二次铜冶炼厂飞灰中存在许多含有氯或溴取代基的有机化学物质，这些物质可能作为二恶英、溴代二恶英和其他类似二恶英化合物形成的前体。在二次铜冶炼厂飞灰中也发现了一些氯化和溴化的 PAH 化合物。在二次铝冶炼厂飞灰样品中，PAHs 是主要的化学物质，其浓度远高于其他工业样品。这表明不同行业存在不同的化学形成途径。在本研究中，对 PAHs 和二恶英的可能形成途径进行了调查和推断。这些结果提高了我们对有毒无意持久性有机污染物形成机制的理解，并有助于减少其源排放。
