Review of Catalysts for Selective Catalytic Reduction (SCR) of NO_x

Abstract

This paper reviews various catalysts for removal of NOx in SCR,including noble metals,zeolites,metal oxides and so on.These traditional catalysts do not have excellent properties in all aspects such as catalytic activity, thermal stability and resistance against poisoning,so they can hardly be commercialized.However,composite type catalysts and storage-reduction catalyst for removal NOx overcome the above disadvantages of traditional catalysts and have promising prospects.

Exploring the Synthesis of Mesoporous In/H-β-NC Catalysts by Desilication Using CTAB Combined with NaOH and Its Application in CH4–SCR of NO

“…It exposed more InO + active sites in the presence of surfactant CTAB, which was consistent with the XPS data. 4 /NO Molar Ratio. The CH 4 /NO molar ratio (1:1, 1.5:1, and 2:1) was used to evaluate the catalytic activity.…”

“…Over the past decade, CH 4 –SCR has gradually become a promising NO x removal technology because of the low cost and easier availability of CH 4 and avoidance of corrosion problems . Among many CH 4 –SCR catalysts, zeolites achieved the loading of various metals or nonmetals due to its rich pore structure and good hydrothermal stability and ion exchange level, so as to maintain high efficiency. , However, the catalysts need to resist poisoning of water vapor and SO 2 in real applications, and the cost of materials for the production of zeolite catalysts should be reduced as much as possible in the full-scale SCR reactors. In order to maintain the catalytic activity in unfavorable environments, lots of research has studied catalysts loaded with monometals, metal oxides, nonprecious metals or bimetals, etc.…”

Pt-based catalysts for NOx reduction from H2 combustion engines

“…4 Nowadays, Cu, Fe, and V-based materials are commonly used as NH 3 -SCR catalysts for cleaning emissions from vehicles. [5][6][7] For ammonia SCR a urea system is needed to produce ammonia, however, in so-called hydrogen SCR, it would be beneficial to be able to use hydrogen directly as a reductant.…”