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Przejdź do strony domowej biblioteki Pedagogiczna Biblioteka Wojewódzka im. Komisji Edukacji Narodowej w Lublinie Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaPedagogiczna Biblioteka Wojewódzka im. Komisji Edukacji Narodowej w Lublinie
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Wyświetlanie 1-10 z 19
Tytuł:
Total oxidation of selected mono-carbon VOCs over hydrotalcite originated metal oxide catalysts
Autorzy:
Wojciechowska, Magdalena
Dudek, Barbara
Witkowski, Stefan
Chmielarz, Lucjan
Piwowarska, Zofia
Michalik, Marek
Rutkowska, Małgorzata
Opis:
Hydrotalcite originated Cu – Mg – Al, Co – Mg – Al and Cu – Co – Mg – Al oxide systems were tested as catalysts for the total oxidation of mono-carbon VOCs (methane, methanol, and formic acid). Both calcination tempera- ture of the hydrotalcite precursors as well as doping of the catalysts with potassium promoter in fl uenced their catalytic activity. Increased calcination temperature, which resulted in a decrease of the surface area of the samples and formation of the spinel phases, activated the Co – Mg – Al catalyst, while the opposite effect was observed for the Cu – Mg – Al and Cu – Co – Mg – Al catalysts. On the other hand doping of the catalysts with potassium promoter signi fi cantly activated the Cu – Mg – Al and Cu – Co – Mg – Al catalysts in the processes of methanol and formic acid conversion, while only slightly in fl uenced the catalytic performance of the Co – Mg – Al sample.
Dostawca treści:
Repozytorium Uniwersytetu Jagiellońskiego
Artykuł
Tytuł:
Electrokinetic properties of silica-titania mixed oxide particles dispersed in aqueous solution of C.I. Direct Yellow 142 dye – effects of surfactant and electrolyte presence
Autorzy:
Chibowski, Stanisław
Wiśniewska, Małgorzata
Wawrzkiewicz, Monika
Hubicki, Zbigniew
Goncharuk, Olena
Tematy:
silica-titania composite
mixed oxides
zeta potential
solid surface charge density
dye adsorption
surfactant effect
Pokaż więcej
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Powiązania:
https://bibliotekanauki.pl/articles/1450752.pdf  Link otwiera się w nowym oknie
Opis:
The mixed $SiO_2$-$TiO_2$ oxide obtained by the pyrogenic method with the silica:titanium percentage ratio equal to 20:80 (ST80) was used in the experiments. The influence of azo dye C.I. Direct Yellow 142 (DY) adsorption at the mixed oxide-solution interface on the electrokinetic properties of solid particles was studied. To determine solid surface charge density and zeta potential of examined suspensions the potentiometric titration and Doppler laser electrophoresis techniques were applied. The changes in structure of electrical double layer formed on the mixed oxide surface in the dye presence were specified as a function of DY concentration, inorganic salt addition and surfactant introduction. The effects of surfactant type and its concentration were determined. Three surfactants of different ionic character (anionic SDS, cationic CTAB and nonionic Triton X-100) were used in measurements. The obtained electrokinetic characteristics of ST80 mixed oxide dispersed in aqueous solutions with various adsorbate compositions is essential for such suspensions stability.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bio-dee synthesis and dehydrogenation coupling of bio-ethanol to bio-butanol over multicomponent mixed metal oxide catalysts
Autorzy:
Kraleva, Elka
Sek, Alicja
Wahaczyk, Ewa
Krysa, Mikolaj
Lew, Agata
Serwicka, Ewa M.
Pieta, Izabela S.
Pieta, Piotr
Lewalska-Graczyk, Agnieszka
Mrdenovic, Dusan
Nowakowski, Robert
Sroka-Bartnicka, Anna
Michalik, Alicja
Wydawca:
MDPI
Cytata wydawnicza:
Catalysts 2021, 11(6), 660; https://doi.org/10.3390/catal11060660
Opis:
The present research was financially supported by the Foundation for Polish Science, co-financed by the European Regional Development Fund under the Smart Growth Operational Programme PO IR, project no. REINTEGRATION/2016-1/5 Waste into fuel-catalyst and process development for waste biomass valorization, www.waste2fuel.edu.pl. I.S.P. and P.P. extend their sincere appreciation to NAWA The Polish National Agency for Academic Exchange through Bekker grants PPN/BEK/2019/1/00348 “C1-C4 alkanes to oxygenated fuel electrochemical transformation” and PPN/BEK/2019/1/00345 “Nanostructured carbon-based materials doped with metal nanoparticles as catalytic electrode materials for CO2 electroreduction with the use of surface-plasmon enhancement”. The research activity of D.M. was supported by funds from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No. 711859 and by financial resources for science in the years 2017–2021 awarded by the Polish Ministry of Science and Higher Education for the implementation of an international co-financed project.
Within the Waste2Fuel project, innovative, high-performance, and cost-effective fuel production methods from municipal solid wastes (MSWs) are sought for application as energy carriers or direct drop-in fuels/chemicals in the near-future low-carbon power generation systems and in-ternal combustion engines. Among the studied energy vectors, C1-C2 alcohols and ethers are mainly addressed. This study presents a potential bio-derived ethanol oxidative coupling in the gas phase in multicomponent systems derived from hydrotalcite-containing precursors. The reaction of alcohol coupling to ethers has great importance due to their uses in different fields. The samples have been synthesized by the co-precipitation method via layered double hydroxide (LDH) material syn-thesis, with a controlled pH, where the M(II)/M(III) ≈ 0.35. The chemical composition and topology of the sample surface play essential roles in catalyst activity and product distribution. The multiple redox couples Ni2+/Ni3+, Cr2+/Cr3+, Mn2+/Mn3+, and the oxygen-vacant sites were considered as the main active sites. The introduction of Cr (Cr3+/Cr4+) and Mn (Mn3+/Mn4+ ) into the crystal lattice could enhance the number of oxygen vacancies and affect the acid/base properties of derived mixed ox-ides, which are considered as crucial parameters for process selectivity towards bio-DEE and bio-butanol, preventing long CH chain formation and coke deposition at the same time.
Dostawca treści:
Repozytorium Centrum Otwartej Nauki
Artykuł
Tytuł:
Effect of copper introduction via wet-impregnation on the performance of Mg-Al mixed metal oxides in selective ammonia oxidation
Autorzy:
Bílková, Tereza
Kupková, Kateřina
Słowik, Grzegorz
Obalová, Lucie
Górecka, Sylwia
Pacultová, Kateřina
Kuśtrowski, Piotr
Górecki, Kamil
Rokicińska, Anna
Opis:
This study investigates catalytic efficiency of Cu-impregnated Mg-Al hydrotalcite-derived mixed metal oxides as selective ammonia oxidation $(NH_{3}-SCO)$ catalysts. Copper was introduced via wet impregnation method onto calcined Mg-Al oxides followed by recalcination at 600 and 800 °C. Cu loading was in range 5–15 wt% to determine the loading effect. Obtained materials were characterized by several techniques (X-ray diffraction, low temperature nitrogen physisorption or temperature programmed reduction) and tested as catalysts of $NH_{3}-SCO$. The study revealed that catalytic activity and selectivity are significantly influenced by copper loading and its surface accessibility rather than calcination temperature. Obtained results highlighted crucial role of dispersed, non-isolated, CuO species in selective and efficient $NH_{3}$ oxidation. The formation of bulk-like species led to unselective oxidation and formation of side products, while presence of isolated CuO species lowers the activity. The characterisation results together with catalytic tests show that enhancing copper accessibility and reducibility on the materials surface result in better catalytic efficiency. The materials impregnation allows greater surface exposure of active copper species compared to materials where Cu was introduced during parent hydrotalcite co-precipitation. Results suggest that use of well-developed surface area support allow copper loading increase without formation of undesired bulk-like species.
Dostawca treści:
Repozytorium Uniwersytetu Jagiellońskiego
Artykuł
Tytuł:
Hydrotalcite derived (Cu, Mn)-Mg-Al metal oxide systems doped with palladium as catalysts for low-temperature methanol incineration
Autorzy:
Jabłońska, Magdalena
Góra-Marek, Kinga
Majda, Dorota
Węgrzyn, Agnieszka
Chmielarz, Lucjan
Piwowarska, Zofia
Wach, Anna
Kuśtrowski, Piotr
Witkowski, Stefan
Bidzińska, Ewa
Opis:
Hydrotalcite derived (Cu, Mn)–Mg–Al mixed metal oxides, synthesized by coprecipitation method, were found to be effective catalysts for methanol incineration. Copper and/or manganese oxides deposited on commercial γ-Al2O3 and MgO were used as the reference catalysts. Cu–Mg–Al–O mixed oxide system was found to be the most active catalysts in a series of the hydrotalcite originated metal oxides and supported samples. On the other hand, copper deposited on Al2O3 and MgO supports were significantly less active than the hydrotalcite derived catalysts. Activity of the catalysts was improved by deposition of small amount of palladium (0.5 wt.%). Temperature-programmed surface reaction method (CH3OH-TPSR) and in situ Fourier-transform infrared spectroscopy (FT-IR) were employed to study the species formed on the catalyst surface during the process of methanol oxidation.
Dostawca treści:
Repozytorium Uniwersytetu Jagiellońskiego
Artykuł
Tytuł:
An influence of thermal treatment conditions of hydrotalcite-like materials on their catalytic activity in the process of $N_2O$ decomposition
Autorzy:
Dudek, Barbara
Dziembaj, Roman
Chmielarz, Lucjan
Piwowarska, Zofia
Kuśtrowski, Piotr
Michalik, Marek
Rutkowska, Małgorzata
Drozdek, Marek
Opis:
Hydrotalcite-like materials containing apart from magnesium and aluminum also copper, cobalt, nickel, and iron were prepared by a co-precipitation method. Thermal transformations of hydrotalcite-like materials were studied by thermal analysis methods as well as XRD, UV-vis-DRS, and XPS measurements of the samples calcined at various temperatures (600, 700, and 800 {\textdegree}C). Calcined hydrotalcites, especially those containing cobalt and copper, were found to be active and selective catalysts of N2O decomposition. It was shown that an increase in the calcination temperature significantly activated the Co-containing catalysts. Promotion of the samples with potassium resulted in activation of the hydrotalcite-based catalysts.
Dostawca treści:
Repozytorium Uniwersytetu Jagiellońskiego
Artykuł
Wyświetlanie 1-10 z 19

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