Precipitated K-Promoted Co-Mn-Al Mixed Oxides for Direct NO Decomposition: Preparation and Properties.

0506324 - ÚCHP 2020 RIV CH eng J - Journal Article
Jirátová, Květa - Pacultová, K. - Balabánová, Jana - Karásková, K. - Klegová, A. - Bílková, T. - Jandová, Věra - Koštejn, Martin - Martaus, A. - Kotarba, A. - Obalová, L.
Precipitated K-Promoted Co-Mn-Al Mixed Oxides for Direct NO Decomposition: Preparation and Properties.
Catalysts. Roč. 9, č. 7 (2019), s. 592. E-ISSN 2073-4344
R&D Projects: GA ČR(CZ) GA18-19519S
Institutional support: RVO:67985858
Keywords : NO decomposition * Co–Mn–Al mixed oxides * catalyst preparation
OECD category: Chemical process engineering
Impact factor: 3.520, year: 2019
Method of publishing: Open access
https://www.mdpi.com/2073-4344/9/7/592

Direct decomposition of nitric oxide (NO) proceeds over Co-Mn-Al mixed oxides promoted by potassium. In this study, answers to the following questions have been searched: Do the properties of the K-promoted Co-Mn-Al catalysts prepared by different methods differ from each other? The K-precipitated Co-Mn-Al oxide catalysts were prepared by the precipitation of metal nitrates with a solution of K 2 CO 3 /KOH, followed by the washing of the precipitate to different degrees of residual K amounts, and by cthe alcination of the precursors at 500 • C. The properties of the prepared catalysts were compared with those of the best catalyst prepared by the K-impregnation of a wet cake of Co-Mn-Al oxide precursors. The solids were characterized by chemical analysis, DTG, XRD, N 2 physisorption, FTIR, temperature programmed reduction (H 2-TPR), temperature programmed CO 2 desorption (CO 2-TPD), X-ray photoelectron spectrometry (XPS), and the species-resolved thermal alkali desorption method (SR-TAD). The washing of the K-precipitated cake resulted in decreasing the K amount in the solid, which affected the basicity, reducibility, and non-linearly catalytic activity in NO decomposition. The highest activity was found at ca 8 wt.% of K, while that of the best K-impregnated wet cake catalyst was at about 2 wt.% of K. The optimization of the cake washing conditions led to a higher catalytic activity.
Permanent Link: http://hdl.handle.net/11104/0299121