The Latest Research Progress of NH3-SCR in the SO2 Resistance of the Catalyst in Low Temperatures for Selective Catalytic Reduction of NOx.

The selective catalytic reduction (SCR) has been widely used in industrial denitrification owing to its high denitrification efficiency, low operating costs, and simple operating procedures. However, coal containing a large amount of sulfur will produce SO₂ during combustion, which makes the catalyst easy to be deactivated, thus limiting the application of this technology. This review summarizes the latest NH₃-SCR reaction mechanisms and the deactivation mechanism of catalyst in SO₂-containing flue gas. Some strategies are summarized for enhancing the poison-resistance through modification, improvement of support, the preparation of complex oxide catalyst, optimizing the preparation methods, and acidification. The mechanism of improving sulfur resistance of catalysts at low temperatures is summarized, and the further development of the catalyst is also prospected. This paper could provide a reference and guidance for the development of SO₂ resistance of the catalyst at low temperatures. [ABSTRACT FROM AUTHOR]