Factors Affecting Mercury Oxidation by SCR Catalysts

Abstract:

The application of selective catalytic reduction (SCR) system may affect mercury speciation in coal-combustion flue gas. The factors affecting mercury oxidation efficiency by SCR catalysts have been evaluated in this research. The influencing factors investigated included hydrogen chloride (HCl), sulfur dioxide (SO₂), ammonia (NH₃) injection rate and space velocity. HCl had been found to promote mercury oxidation significantly. The Eley-Rideal mechanism was proven to be suitable to explain the reaction of Hg⁰ and HCl. NH₃ injection had a strong negative effect to mercury oxidation. The deactivation of aged SCR catalysts was mainly due to loss of active sites.

• Periodical: Advanced Materials Research (Volumes 986-987)
• Pages: 755-760
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.986-987.755
• Online since: July 2014
• Authors: Wen Du*, Li Bao Yin, Yu Qun Zhuo, Qi Sheng Xu, Liang Zhang, Chang He Chen
• Keywords: Flue Gas, Mercury, Oxidation, Scr Catalyst

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