Surface and Texture Characterization of Alumina-Supported Copper and Mixed Copper–Manganese Oxide Catalysts and Their Formate Precursors

Stoilova, D.; Nickolov, R.; Cheshkova, Katinka T.

doi:10.1006/jcis.2000.6905

Cited by 5 publications

(4 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…With 8Mn/Al the well-defined shoulder (Rp = 2.0-3.7 nm) evidences the formation of clusters of active phase supported around the entrances of the admission pores of the initial alumina particles that confines the access to the fine mesopores. Such on effect is observed by Stoilova et al in [28].…”

Section: Characterizationsupporting

confidence: 49%

Adsorption of NO on alumina-supported oxides and oxide–hydroxides of manganese

Spasova

Nikolov

Mehandjiev

2005

Journal of Colloid and Interface Science

View full text Add to dashboard Cite

Section: Characterizationsupporting

confidence: 49%

Adsorption of NO on alumina-supported oxides and oxide–hydroxides of manganese

Spasova

Nikolov

Mehandjiev

2005

Journal of Colloid and Interface Science

View full text Add to dashboard Cite

“…These needles are removed by water washing, and therefore, are neither observed in MnAlT400W nor in MnAlW600. are assigned to the O-H vibration of adsorbed water and/or to surface hydroxyl groups [21], and those between 980-550 cm −1 are attributed to Al-O bond vibrations [22]. The spectra of γ-Al 2 O 3 after calcinations at 400 °C and 600 °C are quite similar to each other, supporting that the γ-Al 2 O 3 support is thermally stable in the range of temperatures studied, which is consistent with the XRD conclusions.…”

Section: Characterization Resultsmentioning

confidence: 99%

Alumina-Supported Manganese Catalysts for Soot Combustion Prepared by Thermal Decomposition of KMnO4

et al. 2012

View full text Add to dashboard Cite

Alumina-supported manganese catalysts with cryptomelane and/or birnessite structure have been prepared using a simple method based on the thermal decomposition of potassium permanganate. The samples have been characterized by XRD, FTIR, TGA, DSC, N 2 adsorption at −196 °C, SEM, H 2 -TPR and XPS, and their catalytic activity for soot combustion has been tested and compared to that of a reference Pt/alumina catalyst. The thermal decomposition of alumina-supported KMnO 4 yields a mixture of supported birnessite and potassium manganate which is the most effective, among those prepared, to lower the soot combustion temperature. However, this material is not useful for soot combustion because the accelerating effect is not based on a catalytic process but on the oxidation of soot by potassium manganate. A suitable soot combustion catalyst is obtained after potassium manganate is removed by water washing, yielding only the birnessite phase OPEN ACCESSCatalysts 2012, 2 353 on the γ-Al 2 O 3 support. This birnessite phase can be transformed into cryptomelane by calcination at 600 °C. These two samples, γ-Al 2 O 3 -supported birnessite and cryptomelane are suitable catalysts for soot combustion in NO x /O 2 mixtures, as their catalytic activity is based on the NO 2 -assited mechanism, that is, both catalysts accelerate the oxidation of NO to NO 2 and NO 2 promotes soot oxidation. The soot combustion temperatures obtained with these birnessite/cryptomelane alumina-supported catalysts are similar to that obtained with the reference Pt/alumina catalyst.

show abstract

“…The band at 2100 cm À1 indicates that the CO molecule adsorbs on Cu + [20,21]. There are also bands at 3700 cm À1 (not shown here) where OH vibrations of metal oxides are postulated [13,17,20]. At 1678 and 1282 cm À1 , bands of chemisorbed CO were recorded.…”

Section: Co At 35°cmentioning

confidence: 98%

“…The bands around 3600 cm À1 are assigned to OH groups of the solid and are not discussed here because of their complexity and low relevance for our study. Other groups have investigated these bands by FT-IR in detail already [13,18,20], so we concentrate in all figures revealing spectra on the 3500-1000 cm À1 range where intermediates of propane and CO are observable. Purging the cell with synthetic air at 375°C after propane and CO adsorption resulted in recovery of the original background spectra before the experiments (not shown here).…”

Section: Co/propane/propane + Co At 375°cmentioning

confidence: 99%