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Roles of ZnO in Cu/Core-Shell Al-MCM-41 for NO Reduction by Selective Catalytic Reduction with NH3: The Effects of Metal Loading and Cu/ZnO Ratio.

ABSTRACT: Cu-ZnO/Al-MCM-41 catalysts were studied for NO x reduction. The total metal loading was varied as 3, 5, and 7 wt %, whereas the Cu-to-ZnO ratio was fixed at 1:1. Too high metal loading led to lower reducibility of Cu2+, as CuO and ZnO covers on the catalyst surface could partially block pores and hinder gas molecules to access the Cu2+ ions. Subsequently, Cu loading was fixed at 2.5 wt %, whereas ZnO content was varied as 0, 2.5, and 3.5 wt %. The results demonstrated that 2.5Cu-2.5ZnO catalyst exhibits the best catalytic activity, as it gave the average NO conversion of 87%.

SUBMITTER: Imyen T

PROVIDER: S-EPMC6358062 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Roles of ZnO in Cu/Core-Shell Al-MCM-41 for NO Reduction by Selective Catalytic Reduction with NH3: The Effects of Metal Loading and Cu/ZnO Ratio.

Imyen Thidarat T Limphirat Wanwisa W Rupprechter Günther G Kongkachuichay Paisan P

ACS omega 20190114 1

Cu-ZnO/Al-MCM-41 catalysts were studied for NO x reduction. The total metal loading was varied as 3, 5, and 7 wt %, whereas the Cu-to-ZnO ratio was fixed at 1:1. Too high metal loading led to lower reducibility of Cu2+, as CuO and ZnO covers on the catalyst surface could partially block pores and hinder gas molecules to access the Cu2+ ions. Subsequently, Cu loading was fixed at 2.5 wt %, whereas ZnO content was varied as 0, 2.5, and 3.5 wt %. The results ...[more]

PMID: 30729222

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