摘要
The concentration ranges of As and Sb in six Late Permian high-arsenic coals collected from Xingren and Xingyi, Guizhou Province are 94.1 μg·g -1-3 2 and 8 1 μg·g -1-120 μg·g -1, respectively. Based on the mineralogical analysis, no arsenic and arsenic-bearing minerals are detected in these samples and arsenic occurs in coal macerals. By extended X-ray absorption fine structure(EXAFS) spectroscopy, we have found that arsenic in these high-arsenic coal samples coordinates with oxygen; the coordination number of As with oxygen for these samples is 4 except one sample(H-9) for which the coordination number of As is 3. Therefore, arsenic in these high-arsenic coals does not occur in sulfide minerals, but occurs in arsenate or arsenite phase, and the preponderance of As is in arsenate of As 5+.
The concentration ranges of As and Sb in six Late Permian high-arsenic coals collected from Xingren and Xingyi, Guizhou Province are 94.1 μg · g-1-3.2% and 8.1 μg · g-1-120 μg · g-1, respectively. Based on the mineralogical analysis, no arsenic and arsenic-bearing minerals are detected in these samples and arsenic occurs in coal macerals. By extended X-ray absorption fine structure(EX-AFS) spectroscopy, we have found that arsenic in these high-arsenic coal samples coordinates with oxygen; the coordination number of As with oxygen for these samples is 4 except one sample(H9) for which the coordination number of As is 3. Therefore, arsenic in these high-arsenic coals does not occur in sulfide minerals, but occurs in arsenate or arsenite phase, and the preponderance of As is in arsenate of As5+.
基金
ThisworkwassupportedbytheNationalNat uralScienceFoundationofChina (GrantNo .49372 12 4)
