Determination of Chemical Speciation of Arsenic and Selenium in High-As Coal Combustion Ash by X‑ray Photoelectron Spectroscopy: Examples from a Kentucky Stoker Ash
| Autor: | Shifeng Dai, Biao Fu, Guijian Liu, James C. Hower, Sarah M. Mardon |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
inorganic chemicals
General Chemical Engineering media_common.quotation_subject Coal combustion products chemistry.chemical_element 010501 environmental sciences 010502 geochemistry & geophysics 01 natural sciences Oxygen complex mixtures Article lcsh:Chemistry X-ray photoelectron spectroscopy Arsenic 0105 earth and related environmental sciences media_common Auger electron spectroscopy Chemistry fungi technology industry and agriculture General Chemistry respiratory system Speciation lcsh:QD1-999 Fly ash Environmental chemistry Selenium |
| Zdroj: | ACS Omega, Vol 3, Iss 12, Pp 17637-17645 (2018) ACS Omega |
| ISSN: | 2470-1343 |
| Popis: | Knowledge of the chemical speciation of arsenic and selenium in coal fly ash is essential in the evaluation of the environmental behavior of fly ash disposed in a landfill in a natural environment. In this study, a series of high-As coal fly ash from stoker boilers were collected to determine the chemical forms of arsenic and selenium. The ash surface chemical characteristics and the speciation of arsenic and selenium were characterized by X-ray photoelectron spectroscopy and X-ray-induced Auger electron spectroscopy. The results indicate that the surface enrichment ratio for selenium (63.3–309.5) is higher than that of arsenic (1.2–21.2). The Wagner chemical-state plot of arsenic indicates that As is mainly present as As(V) bonded to oxygen ligands, that is, the [AsO4]3– anion; Se is found predominantly as elemental Se (62.0–83.3%), followed by selenite (16.7–38%). The extreme enrichment of both arsenic and selenium arsenic is controlled by iron oxides in the coal fly ash. |
| Databáze: | OpenAIRE |
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