Abstract The Hg 0 removal capacities of magnetospheres from fly ash collected from different power plants were investigated at a wide temperature range of 100–400 °C. The relationship between Hg 0… Click to show full abstract
Abstract The Hg 0 removal capacities of magnetospheres from fly ash collected from different power plants were investigated at a wide temperature range of 100–400 °C. The relationship between Hg 0 removal efficiency ( η T ) and iron content/species of magnetospheres was investigated. The magnetospheres attained the optimal Hg 0 removal capacity at 250 °C. The reaction temperature played an important role in Hg 0 adsorption and oxidation behaviors. At low reaction temperature (100 °C and 150 °C), the adsorption of Hg 0 played a predominant role in Hg 0 removal, while the Hg 0 removal mainly depended on the Hg 0 oxidation capacity at high temperature (200–400 °C). The Hg 0 removal capacity increased with the increase of iron content. The percentage of ferrospinel and hematite in magnetospheres is a key factor for determining the Hg 0 removal capacity as well. Hydrogen fluoride (HF) could remove the glass-phase materials on the magnetospheres and the active iron species embedded in the glass phase could be exposed and accessible. After fluorinated by HF, the Hg 0 removal capacity increased in different degree for different magnetospheres, which depended on the content of active iron species in raw magnetospheres.
               
Click one of the above tabs to view related content.