Simultaneous Removal of Hg⁰ and H₂S over a Regenerable Fe₂O₃/AC Catalyst

Abstract

Simultaneous removal of Hg0 and H2S over a regenerable activated coke supported Fe2O3 catalyst (Fe2O3/AC) was studied in simulated coal-derived syngas. It was found that the Fe2O3/AC catalyst exhibited high capability for Hg0 and H2S removal, which was attributed to the catalytic oxidation activity of Fe2O3. Its capability for Hg0 and H2S removal increased with an increase of Fe2O3 loading amount, and the highest was at 150 °C for Hg0 removal. CO and H2 showed no obvious effect on Hg0 removal by Fe2O3/AC, while H2S had a promotion effect, which was due to S and FeSx produced by the H2S reaction on Fe2O3/AC. The results of SEM-EDX and the temperature programmed desorption experiment (TPD) revealed that Fe2O3 played a critical role in Hg0 oxidation, and HgS was generated upon the reaction of Hg0 with H2S on Fe2O3/AC. The used Fe2O3/AC catalyst after Hg0 and H2S removal could be effectively regenerated and still had high capability for Hg0 and H2S removal.

Keywords

• Fe₂O₃/AC
• Hg⁰
• H₂S
• activated coke
• syngas