Deactivation of Pt/Wire-Mesh and Vanadia/Monolith Catalysts Applied in Selective Catalytic Reduction of NOx in Flue Gas

• In this study the deactivation of Pt/wire mesh and vanadia/monolith catalysts by aerosol particles of some inorganic salts (K2SO4, KCl and ZnCl2) with high or low melting points has been investigated. The aerosol particles may either diffuse within the matrix of the catalysts and block the mezzo and micro pores, or deposit on the outer surface of the catalysts and form a porous layer causing a mass transfer resistance that ultimately deactivates the catalysts. It has been observed that in both Pt/wire mesh and vanadia/monolith catalysts the deactivation effect of ZnCl2 was more pronouced compared to other salts. As an example, after 31 hours of exposure to ZnCl2, 10% of the catalysts activities was lost. This may be related to the ZnCl2 lower melting point in comparison with other poisons. These results are in agreement with the previous findings for deactivation of wire-mesh catalysts used for oxidation of volatile organic compounds (VOC) and CO by exposing the catalysts to the aerosols generated from inorganic salts.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Maskinteknik -- Produktionsteknik, arbetsvetenskap och ergonomi (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Mechanical Engineering -- Production Engineering, Human Work Science and Ergonomics (hsv//eng)

Keyword

SCR

pt/wire mesh

vanadia/moolith

aerosol

deactivation

sub-micron particles

Publication and Content Type

art (subject category)

ref (subject category)