环境中黑碳来源解析方法研究进展

摘要

黑碳是燃料不完全燃烧过程中形成的一种特殊的非均质碳颗粒物质，因其具有较高的化学和生物惰性，在全球气候和环境系统中具有重要意义，是当前国际地球和环境科学领域的焦点问题。燃烧条件和燃料来源的不同，使得黑碳的物理化学特性表现出高度的变异，其环境行为及环境效应也具有明显差异，因此对黑碳进行来源解析有利于弄清全球黑碳收支平衡，且能更清晰地认识其在不同环境介质中的迁移转化过程。重点概述了当前国内外常用的几种黑碳来源解析方法及其应用的研究进展；同时提出了未来黑碳来源解析方法的发展方向。稳定碳和放射性碳同位素分析是当前黑碳源解析中应用最多的两种方法，将这两种方法结合不仅能提供更准确的黑碳来源信息，而且能定量估算化石源和生物质源燃烧对黑碳的贡献。多环芳烃特征标志物比值、黑碳/有机碳比值、苯多羧酸分子标志物比值法以及形态特征分析的方法都只能间接地判断黑碳的来源，其方法的应用有一定的局限性和不确定性。未来应加强对不同介质中δ13C的分馏机制及不同排放源样品黑碳的δ13C和14C值域“特征谱”的研究，进一步规范黑碳的分离和测定技术；同时应充分发挥不同分析技术的优势，联合多种方法以获取更多有关黑碳来源、传输和转化过程的信息。%Black carbon (BC) is produced by the incomplete combustion of fossil fuel and biomass, formed a special kind of inhomogeneous carbonaceous particulate matter. BC is highly recalcitrant and persists in the environment for millennia. It is of great significance in the global climate change and environment system, and become the focus of current international earth and environmental sciences. Due to the different combustion condition and the fuel source, the physical and chemical properties of the BC component are complex and highly variable, and the environmental behaviors and effects are also obviously different. Therefore, the source apportionment of BC is very important. It is more conducive to find out the global carbon balance and better know the migration and transformation progress in different environmental media. This paper mainly summarizes the current knowledge of the source apportionment methods of BC as well as the research progress of its application. Finally we put forward the future development direction of methods for BC source apportionment. Stable carbon and radiocarbon isotope analysis are the two mostly used methods in the source apportionment of BC, and the combination of them can not only provide more accurate information of BC source, and can quantitatively estimate the contribution of biomass burning and fossil fuel to BC. The methods of biomarkers ratios of polycyclic aromatic hydrocarbons (PAHs), the ratio of BC to organic carbon (OC), molecular marker ratios of benzene polycarboxylic acids (BPCAs), and morphological analysis can only indirectly determine the BC sources, and the application has limitations and uncertainties. There is a need for further strengthen the study of fractionation mechanism ofδ13C in different media and the domain features ofδ13C and14C for BC in different samples of emission source, and standardize protocols within individual methods for BC analysis. Moreover, there is an ongoing need to give full play to the advantages of different analytical technologies, combined a variety of methods will provide more information about sources, translocation and transformation progresses of BC.