LAUSR

Abstract Samples of magnetic iron–manganese binary oxide supported on activated carbon fiber (Fe 3−x Mn x O 4 /CNF) were prepared for Hg 0 removal from flue gas. The results showed that the Hg 0 removal performance of Fe 3−x Mn x O 4 /CNF was significantly promoted with the increase of Mn incorporating content into Fe 3 O 4 spinel structure. The optimal sample of Fe 2 MnO 4 /CNF, at the optimal reaction temperature of 150–200 °C, attained above 90% of Hg 0 removal efficiency (E a ). CNF played an important role in Hg 0 removal by Fe 3−x Mn x O 4 /CNF due to the disperation of Fe 3−x Mn x O 4 particles and the enhancement for electron transfer process. O 2 enhanced the Hg 0 removal via the Mars-Maessen mechanism, and NO improved the Hg 0 removal performance slightly because of the formation of NO 2 . SO 2 and H 2 O played an inhibitive role in Hg 0 removal due to the competition of active sites for Hg 0 adsorption. A mechanism of Hg 0 removal over Fe 3−x Mn x O 4 /CNF is proposed, in which both Mn cations and lattice/chemisorbed oxygen were thought to the active sites for Hg 0 adsorption/oxidation. Further, the spent Fe 3−x Mn x O 4 /CNF could be regenerated with no obvious decrease of Hg 0 removal performance by water washing followed by thermal treatment at 450 °C in N 2 and calcination at 200 °C in air.