Grzegorz Słowik

Surface State and Catalytic Performance of Ceria‐Supported Cobalt Catalysts in the Steam Reforming of Ethanol

The effect of the particle size and the addition of a K promoter on the oxidation state of Co/CeO2 was investigated and correlated with selectivity for ethanol steam reforming performed with various H2O/EtOH molar ratios. Spectroscopic studies showed that the oxidation state of the catalyst components depends on the H2O/EtOH molar ratio. Surface oxygen‐containing species (OH and Kδ+−Oδ−) are necessary to achieve a good catalyst selectivity, to decrease the amount of coke deposited and to change the nature of the product from fully dehydrogenated C=C to CHx. Besides the surface concentration of oxygen‐containing species, the catalyst morphology and the location at which oxygen‐containing species are chemisorbed may be equally important to their abundance; the selective ceria‐supported Co catalyst should have well‐dispersed Co particles deposited on a well‐dispersed support.

Flow hydrogenation of p-nitrophenol with nano-Ag/Al2O3

Herein, we report the first continuous-flow hydrogenation of p-nitrophenol to p-aminophenol with molecular hydrogen, as a reducing agent. This reaction converts a known pollutant into a high value product with only water as a by product, which is also the solvent. We employed Ag nanoparticles (<5 nm) supported on alumina, which were synthesized directly on low surface area alumina, avoiding the need for catalyst post-processing to confer the required nominal size for flow applications.

Tetrachloromethane as an Effective Agent to Transform Nanoparticles of Palladium and Gold in Supported Catalysts

The use of CCl4 as an effective medium to generate important phase changes in supported Pd and Au catalysts is presented. The dissolution of carbon that originates from CCl4 to form a PdC0.13 solid solution is more complete for the lowest temperature of the CCl4+H2 reaction (30–50 °C). At higher temperatures, the bulk carbiding competes with the hydrogenative removal of bare carbon species to contribute to an enhanced CH4 and C2H6 formation.

P-Arylation of secondary phosphine oxides catalyzed by nickel-supported nanoparticles

A protocol for the cross coupling of aryl halides with secondary phosphine oxides over Ni/CeO2 or Ni/Al2O3 catalysts has been developed for the first time. The advantages offered using this protocol are operational simplicity and the use of an inexpensive heterogeneous nickel catalyst in the absence of any additional ligand. A range of aryl bromides and iodides are coupled with secondary phosphine oxides using low loadings of a catalyst (1 mol%) via this procedure, with good to high yield (up to 86%). Moreover, the influence of nickel particle size and catalyst support on P-arylation of secondary phosphine oxides has also been established.

An application of microemulsion method for synthesis of copper-zinc materials

Abstract Microemulsion method was used for preparation of copperzinc mixed oxides. Samples were prepared from the solutions containing zinc and copper nitrates. Sodium carbonate was used as a precipitant and hydrazine as reducing agent. Water-in-oil (W/O) microemulsions were formed by the application of cyclohexane, isopropyl alcohol, and hexadecyltrimethylammonium bromide (CTAB) as surfactant. The aim of the studies was determination of the influence of the sequence of synthesis stages on the formation of materials, their surface and structural properties. Thermal decomposition studies of materials were carried out by infrared spectroscopy. The physicochemical properties were characterized by nitrogen adsorption-desorption method, X-ray diffraction (XRD) and temperature-programmed reduction (TPR).