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Co-Mn Mixed Oxides Preared by Magnetron Sputtering on Meshes as Catalysts for Oxidation of Organic Compounds.
Jirátová, Květa ; Perekrestov, Roman ; Dvořáková, M. ; Balabánová, Jana ; Koštejn, Martin ; Topka, Pavel ; Kšírová, Petra ; Čada, Martin ; Hubička, Zdeněk ; Kovanda, F.
The catalysts with various Mn content were examined by XRD, SEM, FUR. XPS, and Ih-TPR. tested in the gas-phase oxidation of model organic compound (ethanol) and compared with pelletized commercial Co-Mn- Al mixed oxide catalyst (Astin 2-100, Czech Republic, Co:Mn:Al molar ratio of 4:1:1 ).
Fulltext: content.csg - DOC Plný tet: 00206B6C274C191104151706 - DOC
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MoO3 supported on mesoporous molecular sieves - new catalysts for alkene metathesis and alkyne polymerization
Topka, Pavel ; Čejka, Jiří (advisor) ; Červený, Libor (referee) ; Hlubucek, Vratislav (referee)
Comprehensive Summary of PhD Thesis MoO3 supported on mesoporous molecular sieves - new catalysts for alkene metathesis and alkyne polymerization MoO3 nanesený na mesoporesních molekulových sítech - nové katalyzátory pro metathesi alkenů a polymerizaci alkinů (souhrn disertační práce) Ing. Pavel Topka J. Heyrovský Institute of Physical Chemistry of the ASCR, v. v. i. Department of Physical and Macromolecular Chemistry Faculty of Science, Charles University in Prague Prague, 2008 2 Introduction Modern homogeneous catalysts for metathesis reactions are based on stable carbene complexes especially of Ru, Mo, and W [1]. For large-scale industrial applications, heterogeneous catalysts remain the preferable choice because of low cost, high stability, easy catalyst regeneration and the possibility of easier separation of the catalyst from the reaction mixture. Typical examples are MoO3/SiO2, WO3/SiO2 and Re2O7/Al2O3, without or with cocatalyst (usually tetraalkyltin). Tungsten and molybdenum oxide catalysts require higher reaction temperatures, where side reactions decreasing metathesis selectivity can occur. Only rhenium oxide catalysts exhibit a high activity and selectivity at reaction temperatures below 100 řC. Supported molybdenum oxide catalysts have received much attention because they are widely used in...
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New Biorafination Technologies Developer by Centre Competence BIORAF
Šolcová, Olga ; Hajšlová, J. ; Demnerová, K. ; Vosátka, Miroslav ; Jandejsek, Z. ; Bárnet, M. ; Svátek, A. ; Kaštánek, P. ; Hanika, Jiří ; Topka, Pavel
Fulltext: content.csg - PDF Plný tet: SKMBT_C22014092610432 - PDF
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Sorption Ceramic Membranes with a Functionalized Surface Layer
Zub, Yu.L. ; Tomina, V.V. ; Melnyk, I.V. ; Stolyarchuk, N.V. ; Nazarchuk, H.I. ; Sliesarenko, V.V. ; Sliesarenko, V.M. ; Topka, Pavel ; Šolcová, Olga
In the current work, we have considered and compared the deposition on the surface of ceramic membrane of the polysiloxane layers with different functional groups, such as ≡Si(CH2)3SH, ≡Si(CH2)3NH2, and ≡Si(CH2)2P(O)(OH)2, and ≡Si(CH2)3NHC(S)NHC2H5. We have also reported the fabrication of ceramic membranes with bifunctional polysiloxane surface layers, containing two types of complexing groups of different nature, or (fluoro)alkyl groups along with complexing groups. Tetraethoxysilane and bis(triethoxy)silane structuring agents were used in the study. The identification of the deposited layers on the membrane surface was carried out by IR spectroscopy. It was shown by SEM, that the functionalized layers themselves are usually formed by 50-70 nm nanoparticles and their porous structure depends on several fabrication factors.
Fulltext: content.csg - PDF Plný tet: SKMBT_C22014090110370 - PDF
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Preparation and Characterization of Nanofibrous Catalysts for Environmental Applications
Soukup, Karel ; Topka, Pavel ; Hejtmánek, Vladimír ; Petráš, D. ; Šolcová, Olga
The aim of the study was focused on detailed description of the influence of the preparation of palladium and platinum catalysts supported on polymeric nanofibers based on poly(2,6-dimethyl-1,4-phenylene) oxide on their catalytic performance. The catalytic activity of the prepared electrospun catalysts was investigated by means of model reaction based on total oxidation of methanol. Nanofibrous catalyst supports were prepared by electrospinning technique, which represents currently the most using method to produce polymeric nanofibrous mats. This technique is based on the polymeric fiber elongation under the influence of the electrostatic field between two opposite charged electrodes (capillary electrode and the grounded plate).
Fulltext: content.csg - PDF Plný tet: SKMBT_C22013110613400 - PDF
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Objectives of Centre Competence BIORAF for Recyclable Biological Material Treatment
Šolcová, Olga ; Hajšlová, J. ; Demnerová, K. ; Vosátka, M. ; Jandejsek, Z. ; Bárnet, M. ; Svátek, A. ; Kaštánek, P. ; Hanika, Jiří ; Topka, Pavel
Projekt Bioraf řeší komplexní přeměnu biomasy metodami tzv. zelené chemie na spektrum společensky žádaných produktů s vysokou přidanou hodnotou a energií.
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