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Kejik M, Brus J, Jeremias L, Simonikova L, Moravec Z, Kobera L, Styskalik A, Barnes CE, Pinkas J. Lewis Acidic Aluminosilicates: Synthesis, 27Al MQ/MAS NMR, and DFT-Calculated 27Al NMR Parameters. Inorg Chem 2024; 63:2679-2694. [PMID: 38271593 PMCID: PMC10848260 DOI: 10.1021/acs.inorgchem.3c04035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/21/2023] [Accepted: 12/23/2023] [Indexed: 01/27/2024]
Abstract
Porous aluminosilicates are functional materials of paramount importance as Lewis acid catalysts in the synthetic industry, yet the participating aluminum species remain poorly studied. Herein, a series of model aluminosilicate networks containing [L-AlO3] (L = THF, Et3N, pyridine, triethylphosphine oxide (TEPO)) and [AlO4]- centers were prepared through nonhydrolytic sol-gel condensation reactions of the spherosilicate building block (Me3Sn)8Si8O20 with L-AlX3 (X = Cl, Me, Et) and [Me4N] [AlCl4] compounds in THF or toluene. The substoichiometric dosage of the Al precursors ensured complete condensation and uniform incorporation, with the bulky spherosilicate forcing a separation between neighboring aluminum centers. The materials were characterized by 1H, 13C, 27Al, 29Si, and 31P MAS NMR and FTIR spectroscopies, ICP-OES, gravimetry, and N2 adsorption porosimetry. The resulting aluminum centers were resolved by 27Al TQ/MAS NMR techniques and assigned based on their spectroscopic parameters obtained by peak fitting (δiso, CQ, η) and their correspondence to the values calculated on model structures by DFT methods. A clear correlation between the decrease in the symmetry of the Al centers and the increase of the observed CQ was established with values spanning from 4.4 MHz for distorted [AlO4]- to 15.1 MHz for [THF-AlO3]. Products containing exclusively [TEPO-AlO3] or [AlO4]- centers could be obtained (single-site materials). For L = THF, Et3N, and pyridine, the [AlO4]- centers were formed together with the expected [L-AlO3] species, and a viable mechanism for the unexpected emergence of [AlO4]- was proposed.
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Affiliation(s)
- Martin Kejik
- Department
of Chemistry, Faculty of Science, Masaryk
University, Kotlarska 2, Brno CZ-61137, Czech Republic
| | - Jiri Brus
- Department
of NMR Spectroscopy, Institute of Macromolecular
Chemistry, Czech Academy of Sciences, Heyrovskeho nam. 2, Prague CZ-16206, Czech Republic
| | - Lukas Jeremias
- Department
of Chemistry and Biochemistry, Mendel University
in Brno, Brno CZ-61300, Czech
Republic
| | - Lucie Simonikova
- Department
of Chemistry, Faculty of Science, Masaryk
University, Kotlarska 2, Brno CZ-61137, Czech Republic
| | - Zdenek Moravec
- Department
of Chemistry, Faculty of Science, Masaryk
University, Kotlarska 2, Brno CZ-61137, Czech Republic
| | - Libor Kobera
- Department
of NMR Spectroscopy, Institute of Macromolecular
Chemistry, Czech Academy of Sciences, Heyrovskeho nam. 2, Prague CZ-16206, Czech Republic
| | - Ales Styskalik
- Department
of Chemistry, Faculty of Science, Masaryk
University, Kotlarska 2, Brno CZ-61137, Czech Republic
| | - Craig E. Barnes
- Department
of Chemistry, University of Tennessee, Knoxville, Tennessee 37996-1600, United
States
| | - Jiri Pinkas
- Department
of Chemistry, Faculty of Science, Masaryk
University, Kotlarska 2, Brno CZ-61137, Czech Republic
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2
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Pokorny T, Doroshenko I, Machac P, Simonikova L, Bittova M, Moravec Z, Karaskova K, Skoda D, Pinkas J, Styskalik A. Copper Phosphinate Complexes as Molecular Precursors for Ethanol Dehydrogenation Catalysts. Inorg Chem 2023. [PMID: 38032353 DOI: 10.1021/acs.inorgchem.3c01678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
Nowadays, the production of acetaldehyde heavily relies on the petroleum industry. Developing new catalysts for the ethanol dehydrogenation process that could sustainably substitute current acetaldehyde production methods is highly desired. Among the ethanol dehydrogenation catalysts, copper-based materials have been intensively studied. Unfortunately, the Cu-based catalysts suffer from sintering and coking, which lead to rapid deactivation with time-on-stream. Phosphorus doping has been demonstrated to diminish coking in methanol dehydrogenation, fluid catalytic cracking, and ethanol-to-olefin reactions. This work reports a pioneering application of the well-characterized copper phosphinate complexes as molecular precursors for copper-based ethanol dehydrogenation catalysts enriched with phosphate groups (Cu-phosphate/SiO2). Three new catalysts (CuP-1, CuP-2, and CuP-3), prepared by the deposition of complexes {Cu(SAAP)}n (1), [Cu6(BSAAP)6] (2), and [Cu3(NAAP)3] (3) on the surface of commercial SiO2, calcination at 500 °C, and reduction in the stream of the forming gas 5% H2/N2 at 400 °C, exhibited unusual properties. First, the catalysts showed a rapid increase in catalytic activity. After reaching the maximum conversion, the catalyst started to deactivate. The unusual behavior could be explained by the presence of the phosphate phase, which made Cu2+ reduction more difficult. The phosphorus content gradually decreased during time-on-stream, copper was reduced, and the activity increased. The deactivation of the catalyst could be related to the copper diffusion processes. The most active CuP-1 catalyst reaches a maximum of 73% ethanol conversion and over 98% acetaldehyde selectivity at 325 °C and WHSV = 2.37 h-1.
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Affiliation(s)
- Tomas Pokorny
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic
| | - Iaroslav Doroshenko
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic
| | - Petr Machac
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic
| | - Lucie Simonikova
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic
| | - Miroslava Bittova
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic
| | - Zdenek Moravec
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic
| | - Katerina Karaskova
- Institute of Environmental Technology,CEET, VSB-TUO, CZ-70800 Ostrava, Czech Republic
| | - David Skoda
- Centre of Polymer Systems, Tomas Bata University in Zlin, Tr. Tomase Bati 5678, CZ-76001 Zlin, Czech Republic
| | - Jiri Pinkas
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic
| | - Ales Styskalik
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic
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3
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Pokorny T, Vykoukal V, Machac P, Moravec Z, Scotti N, Roupcova P, Karaskova K, Styskalik A. Ethanol Dehydrogenation over Copper-Silica Catalysts: From Sub-Nanometer Clusters to 15 nm Large Particles. ACS Sustain Chem Eng 2023; 11:10980-10992. [PMID: 37538293 PMCID: PMC10394689 DOI: 10.1021/acssuschemeng.2c06777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 07/07/2023] [Indexed: 08/05/2023]
Abstract
Non-oxidative ethanol dehydrogenation is a renewable source of acetaldehyde and hydrogen. The reaction is often catalyzed by supported copper catalysts with high selectivity. The activity and long-term stability depend on many factors, including particle size, choice of support, doping, etc. Herein, we present four different synthetic pathways to prepare Cu/SiO2 catalysts (∼2.5 wt % Cu) with varying copper distribution: hydrolytic sol-gel (sub-nanometer clusters), dry impregnation (A̅ = 3.4 nm; σ = 0.9 nm and particles up to 32 nm), strong electrostatic adsorption (A̅ = 3.1 nm; σ = 0.6 nm), and solvothermal hot injection followed by Cu particle deposition (A̅ = 4.0 nm; σ = 0.8 nm). All materials were characterized by ICP-OES, XPS, N2 physisorption, STEM-EDS, XRD, RFC N2O, and H2-TPR and tested in ethanol dehydrogenation from 185 to 325 °C. The sample prepared by hydrolytic sol-gel exhibited high Cu dispersion and, accordingly, the highest catalytic activity. Its acetaldehyde productivity (2.79 g g-1 h-1 at 255 °C) outperforms most of the Cu-based catalysts reported in the literature, but it lacks stability and tends to deactivate over time. On the other hand, the sample prepared by simple and cost-effective dry impregnation, despite having Cu particles of various sizes, was still highly active (2.42 g g-1 h-1 acetaldehyde at 255 °C). Importantly, it was the most stable sample out of the studied materials. The characterization of the spent catalyst confirmed its exceptional properties: it showed the lowest extent of both coking and particle sintering.
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Affiliation(s)
- Tomas Pokorny
- Department
of Chemistry, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech
Republic
| | - Vit Vykoukal
- Department
of Chemistry, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech
Republic
| | - Petr Machac
- Department
of Chemistry, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech
Republic
| | - Zdenek Moravec
- Department
of Chemistry, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech
Republic
| | - Nicola Scotti
- Consiglio
Nazionale delle Ricerche, Istituto di Scienze e Tecnologie Chimiche
“G. Natta”, Via Golgi 19, 20133 Milano, Italy
| | - Pavla Roupcova
- Institute
of Physics of Materials, Academy of Sciences
of the Czech Republic, Zizkova 22, CZ-61662 Brno, Czech Republic
- CEITEC
Brno University of Technology, Purkynova 123, CZ-61200 Brno, Czech Republic
| | - Katerina Karaskova
- Institute
of Environmental Technology, CEET, VSB-TUO, 17. listopadu 2172/15, CZ-70800 Ostrava, Czech Republic
| | - Ales Styskalik
- Department
of Chemistry, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech
Republic
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Podhorsky J, Babiak M, Pinkas J, Hegemann C, Mathur S, Moravec Z. New mixed-ligand organoaluminum heteroarylalkenolates. Polyhedron 2021. [DOI: 10.1016/j.poly.2020.114953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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5
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Podhorsky J, Murauskas T, Hegemann C, Graf D, Fischer T, Babiak M, Pinkas J, Plausinaitiene V, Mathur S, Abrutis A, Moravec Z. Preparation of Heteroleptic Tin(IV) N,O‐β‐Heteroarylalkenolate Complexes and Their Properties as PI‐MOCVD Precursors for SnO
2
Deposition. Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201800913] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Jan Podhorsky
- Masaryk University Faculty of Science Department of Chemistry Kotlarska 2 611 37 Brno Czech Republic
| | - Tomas Murauskas
- University of Vilnius Faculty of Chemistry and Geosciences Naugarduko 24 03225 Vilnius Lithuania
| | - Corinna Hegemann
- University of Cologne Faculty of Mathematics and Natural Sciences, Department of Chemistry Greinstraße 6 50939 Köln Germany
| | - David Graf
- University of Cologne Faculty of Mathematics and Natural Sciences, Department of Chemistry Greinstraße 6 50939 Köln Germany
| | - Thomas Fischer
- University of Cologne Faculty of Mathematics and Natural Sciences, Department of Chemistry Greinstraße 6 50939 Köln Germany
| | - Michal Babiak
- Masaryk University Faculty of Science Department of Chemistry Kotlarska 2 611 37 Brno Czech Republic
- Masaryk University CEITEC MU Kamenice 5 62500 Brno Czech Republic
| | - Jiri Pinkas
- Masaryk University Faculty of Science Department of Chemistry Kotlarska 2 611 37 Brno Czech Republic
- Masaryk University CEITEC MU Kamenice 5 62500 Brno Czech Republic
| | - Valentina Plausinaitiene
- University of Vilnius Faculty of Chemistry and Geosciences Naugarduko 24 03225 Vilnius Lithuania
| | - Sanjay Mathur
- University of Cologne Faculty of Mathematics and Natural Sciences, Department of Chemistry Greinstraße 6 50939 Köln Germany
| | - Adulfas Abrutis
- University of Vilnius Faculty of Chemistry and Geosciences Naugarduko 24 03225 Vilnius Lithuania
| | - Zdenek Moravec
- Masaryk University Faculty of Science Department of Chemistry Kotlarska 2 611 37 Brno Czech Republic
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6
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Koudelkova Z, Syrovy T, Ambrozova P, Moravec Z, Kubac L, Hynek D, Richtera L, Adam V. Determination of Zinc, Cadmium, Lead, Copper and Silver Using a Carbon Paste Electrode and a Screen Printed Electrode Modified with Chromium(III) Oxide. Sensors (Basel) 2017; 17:s17081832. [PMID: 28792450 PMCID: PMC5580028 DOI: 10.3390/s17081832] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Revised: 07/28/2017] [Accepted: 08/04/2017] [Indexed: 01/08/2023]
Abstract
In this study, the preparation and electrochemical application of a chromium(III) oxide modified carbon paste electrode (Cr-CPE) and a screen printed electrode (SPE), made from the same material and optimized for the simple, cheap and sensitive simultaneous determination of zinc, cadmium, lead, copper and the detection of silver ions, is described. The limits of detection and quantification were 25 and 80 µg·L-1 for Zn(II), 3 and 10 µg·L-1 for Cd(II), 3 and 10 µg·L-1 for Pb(II), 3 and 10 µg·L-1 for Cu(II), and 3 and 10 µg·L-1 for Ag(I), respectively. Furthermore, this promising modification was transferred to the screen-printed electrode. The limits of detection for the simultaneous determination of zinc, cadmium, copper and lead on the screen printed electrodes were found to be 350 µg·L-1 for Zn(II), 25 µg·L-1 for Cd(II), 3 µg·L-1 for Pb(II) and 3 µg·L-1 for Cu(II). Practical usability for the simultaneous detection of these heavy metal ions by the Cr-CPE was also demonstrated in the analyses of wastewaters.
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Affiliation(s)
- Zuzana Koudelkova
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, Brno CZ-613 00, Czech Republic.
| | - Tomas Syrovy
- Department of Graphic Arts and Photophysics, University of Pardubice Doubravice 41, Pardubice CZ-533 53, Czech Republic.
- Center of Materials and Nanotechnologies, Faculty of Chemical Technology, University of Pardubice, Cs. Legii square 565, Pardubice CZ-53002, Czech Republic.
| | - Pavlina Ambrozova
- Department of Geology and Pedology, Mendel University in Brno, Zemedelska 1, Brno CZ-613 00, Czech Republic.
| | - Zdenek Moravec
- Department of Chemistry, Masaryk University, Kotlarska 2, Brno CZ-61137, Czech Republic.
| | - Lubomir Kubac
- Center of Materials and Nanotechnologies, Faculty of Chemical Technology, University of Pardubice, Cs. Legii square 565, Pardubice CZ-53002, Czech Republic.
- Centre for Organic Chemistry Ltd., Rybitvi 296, Rybitvi CZ-533 54, Czech Republic.
| | - David Hynek
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, Brno CZ-613 00, Czech Republic.
- Central European Institute of Technology, Brno University of Technology, Purkynova 123, Brno CZ-612 00, Czech Republic.
| | - Lukas Richtera
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, Brno CZ-613 00, Czech Republic.
- Central European Institute of Technology, Brno University of Technology, Purkynova 123, Brno CZ-612 00, Czech Republic.
| | - Vojtech Adam
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, Brno CZ-613 00, Czech Republic.
- Central European Institute of Technology, Brno University of Technology, Purkynova 123, Brno CZ-612 00, Czech Republic.
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7
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Styskalik A, Skoda D, Moravec Z, Barnes CE, Pinkas J. Surface reactivity of non-hydrolytic silicophosphate xerogels: a simple method to create Brønsted or Lewis acid sites on porous supports. NEW J CHEM 2016. [DOI: 10.1039/c5nj02928g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reactivity of residual acetoxy and trimethylsilyloxy groups is studied in order to introduce new moieties into the surface of silicophosphates.
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Affiliation(s)
- Ales Styskalik
- Department of Chemistry
- Masaryk University
- CZ-61137 Brno
- Czech Republic
- Masaryk University
| | - David Skoda
- Department of Chemistry
- Masaryk University
- CZ-61137 Brno
- Czech Republic
- Masaryk University
| | - Zdenek Moravec
- Department of Chemistry
- Masaryk University
- CZ-61137 Brno
- Czech Republic
| | | | - Jiri Pinkas
- Department of Chemistry
- Masaryk University
- CZ-61137 Brno
- Czech Republic
- Masaryk University
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8
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Skoda D, Styskalik A, Moravec Z, Bezdicka P, Bursik J, Mutin PH, Pinkas J. Mesoporous SnO2–SiO2 and Sn–silica–carbon nanocomposites by novel non-hydrolytic templated sol–gel synthesis. RSC Adv 2016. [DOI: 10.1039/c6ra16556g] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A novel non-hydrolytic sol–gel (NHSG) synthesis of mesoporous tin silicate xerogels is presented.
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Affiliation(s)
- David Skoda
- Masaryk University
- Department of Chemistry
- CZ-61137 Brno
- Czech Republic
- Masaryk University
| | - Ales Styskalik
- Masaryk University
- Department of Chemistry
- CZ-61137 Brno
- Czech Republic
- Masaryk University
| | - Zdenek Moravec
- Masaryk University
- Department of Chemistry
- CZ-61137 Brno
- Czech Republic
| | - Petr Bezdicka
- Institute of Inorganic Chemistry ASCR
- CZ-25068 Husinec-Rez
- Czech Republic
| | - Jiri Bursik
- Institute of Physics of Materials ASCR
- CZ-616 62 Brno
- Czech Republic
| | - P. Hubert Mutin
- Institut Charles Gerhardt UMR 5253 CNRS-UM-ENSCM
- Université de Montpellier
- 34095 Montpellier Cedex 05
- France
| | - Jiri Pinkas
- Masaryk University
- Department of Chemistry
- CZ-61137 Brno
- Czech Republic
- Masaryk University
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9
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Skoda D, Styskalik A, Moravec Z, Bezdicka P, Babiak M, Klementova M, Barnes CE, Pinkas J. Novel non-hydrolytic templated sol–gel synthesis of mesoporous aluminosilicates and their use as aminolysis catalysts. RSC Adv 2016. [DOI: 10.1039/c5ra24563j] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A novel non-hydrolytic sol–gel (NHSG) synthesis of mesoporous aluminosilicate xerogels is presented.
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Affiliation(s)
- David Skoda
- Department of Chemistry
- Masaryk University
- CZ-61137 Brno
- Czech Republic
- CEITEC MU
| | - Ales Styskalik
- Department of Chemistry
- Masaryk University
- CZ-61137 Brno
- Czech Republic
- CEITEC MU
| | - Zdenek Moravec
- Department of Chemistry
- Masaryk University
- CZ-61137 Brno
- Czech Republic
| | - Petr Bezdicka
- Institute of Inorganic Chemistry of the ASCR, v.v.i
- CZ-25068 Husinec-Rez
- Czech Republic
| | - Michal Babiak
- Department of Chemistry
- Masaryk University
- CZ-61137 Brno
- Czech Republic
- CEITEC MU
| | - Mariana Klementova
- Institute of Inorganic Chemistry of the ASCR, v.v.i
- CZ-25068 Husinec-Rez
- Czech Republic
| | | | - Jiri Pinkas
- Department of Chemistry
- Masaryk University
- CZ-61137 Brno
- Czech Republic
- CEITEC MU
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10
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Jeremias L, Nečas M, Moravec Z, Trávníček Z, Novosad J. Syntheses and X-ray structures of heteroleptic octahedral Mn(II)-xanthato complexes involving N-donor ligands. J COORD CHEM 2015. [DOI: 10.1080/00958972.2015.1102228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- L. Jeremias
- Faculty of Science, Department of Chemistry, Masaryk University, Brno, Czech Republic
| | - M. Nečas
- Faculty of Science, Department of Chemistry, Masaryk University, Brno, Czech Republic
- Research Group (Synthesis and Analysis of Nanostructures Structure of Biosystems and Molecular Materials), CEITEC – Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Z. Moravec
- Faculty of Science, Department of Chemistry, Masaryk University, Brno, Czech Republic
| | - Z. Trávníček
- Faculty of Science, Department of Inorganic Chemistry, Palacký University, Olomouc, Czech Republic
| | - J. Novosad
- Faculty of Science, Department of Chemistry, Masaryk University, Brno, Czech Republic
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11
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Doroshenko I, Zurkova J, Moravec Z, Bezdicka P, Pinkas J. Sonochemical precipitation of amorphous uranium phosphates from trialkyl phosphate solutions and their thermal conversion to UP2O7. Ultrason Sonochem 2015; 26:157-162. [PMID: 25640684 DOI: 10.1016/j.ultsonch.2015.01.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 12/29/2014] [Accepted: 01/19/2015] [Indexed: 05/27/2023]
Abstract
Insoluble amorphous precipitates containing uranyl and phosphate ions are obtained by sonication of solutions of three uranyl precursors, UO2(X)2, X=NO3, CH3COO, CH3C(O)CHC(O)CH3 (acetylacetonate, acac), in triesters of phosphoric acid, OP(OR)3, R=Me (trimethyl phosphate, TMP), Et (triethyl phosphate, TEP). TMP and TEP are used as high-boiling solvents and they serve also as a source of phosphate anions. Sonolysis experiments were carried out under flow of Ar at 40°C on a Sonics and Materials VXC 500W system (f=20 kHz, Pac=0.49 W cm(-3)). Powder X-ray diffraction (PXRD) reveals amorphous character of all obtained precipitates. The presence of uranyl and phosphate is evidenced by IR spectroscopy and ICP-OES analysis reveals the content of both U (38.6-43.4 wt%) and P (11.0-13.6 wt%). The thermal behavior of the substances was studied by TG/DSC analysis, which shows weight losses in the range of 19.21-24.08%. On heating the amorphous precipitates to 1000°C, crystalline uranium diphosphate UP2O7 is obtained in all cases as the only crystalline phase. Uranyl(VI) is reduced during thermolysis to U(IV) as there is no characteristic vibration of UO2(2+) in the IR spectra of solid UP2O7 products. The ICP-OES analysis of U and P content in precipitates allowed us to calculate the efficiency of precipitation of uranium from mother liquor and to compare it with the efficiency calculated from the data received by the PXRD and TG/DSC analyses. The efficiency of the uranium removal attained by our sonoprecipitation procedure was typically 30-35%. These sonochemical precipitation reactions providing insoluble uranium phosphates may be potentially interesting models for the description of behavior of uranium-containing waste or reprocessing streams.
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Affiliation(s)
- Iaroslav Doroshenko
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic; Central European Institute of Technology (CEITEC), Masaryk University, CZ-62500 Brno, Czech Republic
| | - Jana Zurkova
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic
| | - Zdenek Moravec
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic
| | - Petr Bezdicka
- Institute of Inorganic Chemistry ASCR, CZ-25068 Rez, Czech Republic
| | - Jiri Pinkas
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic; Central European Institute of Technology (CEITEC), Masaryk University, CZ-62500 Brno, Czech Republic.
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12
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Styskalik A, Skoda D, Moravec Z, Roupcova P, Barnes CE, Pinkas J. Non-aqueous template-assisted synthesis of mesoporous nanocrystalline silicon orthophosphate. RSC Adv 2015. [DOI: 10.1039/c5ra10982e] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Mesoporous nanocrystalline silicon orthophosphate Si5P6O25 was synthesized by the non-hydrolytic sol–gel reaction in the presence of Pluronic P123 template and displays superior catalytic activity and selectivity in methylstyrene dimerization.
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Affiliation(s)
- Ales Styskalik
- Masaryk University
- Department of Chemistry
- CZ-61137 Brno
- Czech Republic
- CEITEC MU
| | - David Skoda
- Masaryk University
- Department of Chemistry
- CZ-61137 Brno
- Czech Republic
- CEITEC MU
| | - Zdenek Moravec
- Masaryk University
- Department of Chemistry
- CZ-61137 Brno
- Czech Republic
| | - Pavla Roupcova
- CEITEC BUT
- Brno University of Technology
- 616 00 Brno
- Czech Republic
| | - Craig E. Barnes
- University of Tennessee
- Department of Chemistry
- TN 37996-1600
- USA
| | - Jiri Pinkas
- Masaryk University
- Department of Chemistry
- CZ-61137 Brno
- Czech Republic
- CEITEC MU
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Chyba J, Moravec Z, Necas M, Mathur S, Pinkas J. Construction of Larger Molecular Aluminophosphate Cages from the Cyclic Four-Ring Building Unit. Inorg Chem 2014; 53:3753-62. [DOI: 10.1021/ic500083a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jan Chyba
- Department
of Chemistry, Faculty of Science, Masaryk University, Kotlarska
2, CZ-61137 Brno, Czech Republic
- Central
European Institute of Technology (CEITEC), Masaryk University, CZ-62500 Brno, Czech Republic
| | - Zdenek Moravec
- Department
of Chemistry, Faculty of Science, Masaryk University, Kotlarska
2, CZ-61137 Brno, Czech Republic
- Central
European Institute of Technology (CEITEC), Masaryk University, CZ-62500 Brno, Czech Republic
| | - Marek Necas
- Department
of Chemistry, Faculty of Science, Masaryk University, Kotlarska
2, CZ-61137 Brno, Czech Republic
- Central
European Institute of Technology (CEITEC), Masaryk University, CZ-62500 Brno, Czech Republic
| | - Sanjay Mathur
- Institute
of Inorganic Chemistry, University of Cologne, Greinstrasse 6, D-50939, Cologne, Germany
| | - Jiri Pinkas
- Department
of Chemistry, Faculty of Science, Masaryk University, Kotlarska
2, CZ-61137 Brno, Czech Republic
- Central
European Institute of Technology (CEITEC), Masaryk University, CZ-62500 Brno, Czech Republic
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Spichal Z, Hegrova B, Moravec Z, Pinkas J, Necas M. Synthesis and structure of lanthanide complexes with large-bite diphosphine dioxide ligands. Polyhedron 2011. [DOI: 10.1016/j.poly.2011.03.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Pinkas J, Brlejova Z, Kratochvil J, Moravec Z, Roesky HW. POLYHEDRAL METALLOPHOSPHONATES AND -SILICATES: SYNTHESIS, FUNCTIONALIZATION, AND TRANSFORMATIONS. PHOSPHORUS SULFUR 2010. [DOI: 10.1080/10426500490429149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Moravec Z, Sluka R, Necas M, Jancik V, Pinkas J. A Structurally Diverse Series of Aluminum Chloride Alkoxides [ClxAl(μ-OR)y]n(R =nBu,cHex, Ph, 2,4-tBu2C6H3). Inorg Chem 2009; 48:8106-14. [DOI: 10.1021/ic802251g] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Pinkas J, Reichlova V, Zboril R, Moravec Z, Bezdicka P, Matejkova J. Sonochemical synthesis of amorphous nanoscopic iron(III) oxide from Fe(acac)3. Ultrason Sonochem 2008; 15:257-64. [PMID: 17507278 DOI: 10.1016/j.ultsonch.2007.03.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2006] [Accepted: 03/23/2007] [Indexed: 05/15/2023]
Abstract
Amorphous nanoscopic iron(III) oxide with interesting magnetic properties was prepared by sonolysis of Fe(acac)(3) under Ar in tetraglyme with a small amount of added water. The organics content and the surface area of the Fe(2)O(3) nanoparticles can be controlled with an amount of water in the reaction mixture and it increases from 48 m(2)g(-1) for dry solvent up to 260 m(2)g(-1) when wet Ar is employed. For further monitoring of the particle size and morphology and for the study of the surface, magnetic and thermal properties, the sample with 2 vol.% of H(2)O was chosen. SEM showed nanoscopic composite particles of a uniform size distribution and nearly spherical shapes with an estimated diameter of 20 nm. Such composites are built from amorphous iron(III) oxide nanoparticles (3 nm) embedded in an acetate matrix as proved by TEM and IR spectroscopy. Temperature-dependent Mössbauer spectra demonstrate a very narrow magnetic transition with an unusually low transition temperature around 25K reflecting the system of magnetically non-interacting ultrasmall particles with a narrow size distribution. The in-field (5T) Mössbauer spectrum recorded at 5K shows a minimum change compared to the zero-field spectrum indicating an absence of the long-range magnetic ordering. The composite particles are thermally stable up to 150 degrees C, which is confirmed by DSC, TG, and by the constant surface area. At higher temperatures, acetate groups are removed from the particle surface, which is documented by the increased surface area and disappearance of their IR bands.
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Affiliation(s)
- Jiri Pinkas
- Department of Inorganic Chemistry, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic.
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Smrcka V, Stingl J, Kubín K, Moravec Z. [Anatomic observations on the use of the gastrocnemius muscle in the preparation of muscle flaps]. Rozhl Chir 1987; 66:291-7. [PMID: 3589854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Spicka J, Moravec Z. [Diabetes insipidus: treatment]. Vnitr Lek 1972; 18:695-8. [PMID: 5046401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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