Abstract：Microwave digestion is the most common method for pretreating coal fly ash and flue gas desulfurization (FGD) gypsum before determination of the trace elements in the flow streams. This study analyzes previous microwave digestion methods. Then, the standard microwave digestion method 3052 from the US Environment Protection Agency is used to design three acid systems using HNO3, HNO3-HCl and HNO3-HF-H3BO3 for digesting certified reference gypsum material (FGD-2). After digestion, the As, Be, Cd, Co, Cr, Mn, Pb and Se contents are determined using inductively coupled plasma mass spectrometry (ICP-MS). The results show that HNO3-HF-H3BO3 gives the best digestion. The Cr, Mn and Se recoveries are 93.5%, 88.0% and 97.7%. Tests using a fly ash (GBW 08401) reference material also show good results with the As, Co, Cr, Mn, Pb and Se recoveries between 90.6% and 101.8%, but the Be and Cd recoveries are not good enough. This method can be used to determine the trace elements in coal fly ash and FGD gypsum by microwave digestion with HNO3-HF-H3BO3 followed by ICP-MS analysis.
朱振武, 禚玉群. 不同酸体系对微波消解法测量燃煤副产物中痕量元素的影响[J]. 清华大学学报（自然科学版）, 2016, 56(10): 1072-1078.
ZHU Zhenwu, ZHUO Yuqun. Effect of acid systems for determination of trace elements in coal combustion byproductsusing microwave digestion method. Journal of Tsinghua University(Science and Technology), 2016, 56(10): 1072-1078.
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2016, Vol. 56 
