Ceria supported on sulfated zirconia as a superacid catalyst for selective catalytic reduction of NO with NH_3

摘要

In this paper, ceria supported on sulfated zirconia (CeSZ) as a superacid catalyst was synthesized and the resulted performances for selective catalytic reduction (SCR) of NO with NH_3 were investigated. Experimental results revealed that the sulfation of zirconia supports could greatly improve the SCR activity of the catalysts. Among the tested samples, the CeSZ catalyst with Ce/Zr mole ratio at 0.095 possessed the highest NO conversion (i.e., 98.6% at ca. 420°C and 180,000h~(-1)). The sulfation had led to a formation of pure tetragonal phase of ZrO_2, a well dispersion of CeO_2, abundant stable superacid sites, increasing surface area and enrichment of Ce~(3+) on the surface, all of which were responsible for its excellent performance in SCR of NO with NH_3.