Preparation of Keggin-Type H3−xMx[PW11CrO40]/SiO2 (M = Co or Fe) and Their Catalytic Activity in Oxidation of Benzyl Alcohol

The aim of the study was to establish the influence of a co-precipitation agent (i.e., NaOH–immediate precipitation; hexamethylenetetramine/urea–gradual precipitation and growth of nanostructures) on the properties and catalytic activity of as-synthesized Au-CeO2 nanocomposites. All catalysts were fully characterized with the use of XRD, nitrogen physisorption, ICP-OES, SEM, HR-TEM, UV-vis, XPS, and tested in low-temperature oxidation of benzyl alcohol as a model oxidation reaction. The results obtained in this study indicated that the type of co-precipitation agent has a significant impact on the growth of gold species. Immediate co-precipitation of Au-CeO2 nanostructures with the use of NaOH allowed obtainment of considerably smaller and more homogeneous in size gold nanoparticles than those formed by gradual co-precipitation and growth of Au-CeO2 nanostructures in the presence of hexamethylenetetramine or urea. In the catalytic tests, it was established that the key factor promoting high activity in low-temperature oxidation of benzyl alcohol was size of gold nanoparticles. The highest conversion of the alcohol was observed for the catalyst containing the smallest Au particle size (i.e., Au-CeO2 nanocomposite prepared with the use of NaOH as a co-precipitation agent).

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On the selective aerobic oxidation of benzyl alcohol with Pd/Au-nanoparticles in batch and flow

Nanotechnology Reviews ◽

10.1515/ntrev-2012-0085 ◽

2014 ◽

Vol 3 (1) ◽

pp. 99-110 ◽

Cited By ~ 2

Author(s):

Hannes Alex ◽

Norbert Steinfeldt ◽

Klaus Jähnisch ◽

Matthias Bauer ◽

Sandra Hübner

Keyword(s):

Catalytic Activity ◽

Benzyl Alcohol ◽

Aerobic Oxidation ◽

X Ray ◽

X Ray Scattering ◽

Oxidation Of Benzyl Alcohol ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Selective Aerobic Oxidation

AbstractNanoparticles (NP) have specific catalytic properties, which are influenced by parameters like their size, shape, or composition. Bimetallic NPs, composed of two metal elements can show an improved catalytic activity compared to the monometallic NPs. We, herein, report on the selective aerobic oxidation of benzyl alcohol catalyzed by unsupported Pd/Au and Pd NPs at atmospheric pressure. NPs of varying compositions were synthesized and characterized by UV/Vis spectroscopy, transmission electron microscopy (TEM), and small-angle X-ray scattering (SAXS). The NPs were tested in the model reaction regarding their catalytic activity, stability, and recyclability in batch and continuous procedure. Additionally, in situ extended X-ray absorption fine structure (EXAFS) measurements were performed in order to get insight in the process during NP catalysis.

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Selective oxidation of benzyl alcohol to benzaldehyde with H2O2 in water on epichlorohydrin-modified Fe3O4 microspheres

New Journal of Chemistry ◽

10.1039/c5nj00434a ◽

2015 ◽

Vol 39 (6) ◽

pp. 4924-4932 ◽

Cited By ~ 41

Author(s):

Shiwei Xiao ◽

Chuntao Zhang ◽

Rong Chen ◽

Fengxi Chen

Keyword(s):

Catalytic Activity ◽

Benzyl Alcohol ◽

Selective Oxidation ◽

Title Reaction ◽

Enhancing Effect ◽

Oxidation Of Benzyl Alcohol ◽

Fe3o4 Microspheres

The enhancing effect of modification by epichlorohydrin on the catalytic activity of Fe3O4 microspheres in the title reaction was theoretically and experimentally confirmed.

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