Details

Autor(en) / Beteiligte

• Zhou, Jinsong
• Hou, Wenhui
• Qi, Pan
• Gao, Xiang
• Luo, Zhongyang
• Cen, Kefa

Titel

CeO2–TiO2 Sorbents for the Removal of Elemental Mercury from Syngas

Ist Teil von

• Environmental science & technology, 2013-09, Vol.47 (17), p.10056-10062

Ort / Verlag

Washington, DC: American Chemical Society

Erscheinungsjahr

2013

Quelle

MEDLINE

Beschreibungen/Notizen

• A series of CeO2–TiO2 (CeTi) sorbents with different CeO2/TiO2 mass ratios were prepared by an impregnation method and employed to remove elemental mercury (Hg0) in simulated syngas. The CeTi sorbents with a CeO2/TiO2 mass ratio of 0.2 exhibited superior Hg0 removal efficiency from 80 to 150 °C, which could be ascribed to the greater amount of surface chemisorbed oxygen resulted from Ce3+ on the sample surface. H2S was the most effective syngas component responsible for Hg0 removal. The use of 400 ppm H2S resulted in 98% Hg0 removal efficiency under the experimental conditions. H2 and CO had a negligible effect on the efficiency of Hg removal. In the presence of H2S, a prohibitive effect of HCl and NH3 on Hg0 removal was observed because of the consumption of the surface oxygen. Water vapor also inhibited Hg0 removal due to competitive adsorption with H2S. Hg0 removal over CeTi sorbents was proposed to follow the Eley–Rideal mechanism, in which active surface sulfur reacts with gas-phase Hg0. This large oxygen storage capacity of CeTi sorbents is quite favorable to H2S catalytic oxidation and Hg0 emission control in an extremely reducing environment, such as when there is a deficiency of O2.