Tailored Alkali Resistance of DeNO_x Catalysts by Improving Redox Properties and Activating Adsorbed Reactive Species.

ABSTRACT: It is still challenging to develop strongly alkali-resistant catalysts for selective catalytic reduction of NO_x with NH₃. It is generally believed that the maintenance of acidity is the most important factor because of neutral effects of alkali. This work discovers that the redox properties rather than acidity play decisive roles in improving alkali resistance of some specific catalyst systems. K-poisoned Fe-decorated SO₄^2--modified CeZr oxide (Fe/SO₄^2-/CeZr) catalysts show decreased acidity but reserve the high redox properties. The higher reactivity of NH_x species induced by K poisoning compensates for the decreased amount of adsorbed NH_x, leading to a desired reaction efficiency between adsorbed NH_x and nitrate species. This study provides a unique perspective in designing an alkali-resistant deNO_x catalyst via improving redox properties and activating the reactivities of NH_x species rather than routinely increasing acidic sites for NH_x adsorption, which is of significance for academic interests and practical applications.

SUBMITTER: Khan MN 

PROVIDER: S-EPMC7262565 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature