Green Epoxidation of Olefins with Zn<sub>x</sub>Al/Mg<sub>x</sub>Al-LDH Compounds: Influence of the Chemical Composition
This contribution concerns the effect of the chemical composition of the brucite-type layer of bi-cationic LDH materials Zn<sub>x</sub>Al and Mg<sub>x</sub>Al (x = 2–5) and tri-cationic LDH Mg<sub>y</sub>Zn<sub>z</sub>Al (y + z = 4, y = 1, 2, 3) on the...
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MDPI AG
2022-01-01
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| Series: | Catalysts |
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| Online Access: | https://www.mdpi.com/2073-4344/12/2/145 |
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| author | Rodica Zăvoianu Anca Cruceanu Octavian Dumitru Pavel Corina Bradu Mihaela Florea Ruxandra Bîrjega |
| author_facet | Rodica Zăvoianu Anca Cruceanu Octavian Dumitru Pavel Corina Bradu Mihaela Florea Ruxandra Bîrjega |
| author_sort | Rodica Zăvoianu |
| collection | DOAJ |
| description | This contribution concerns the effect of the chemical composition of the brucite-type layer of bi-cationic LDH materials Zn<sub>x</sub>Al and Mg<sub>x</sub>Al (x = 2–5) and tri-cationic LDH Mg<sub>y</sub>Zn<sub>z</sub>Al (y + z = 4, y = 1, 2, 3) on their catalytic activity for olefin epoxidation with H<sub>2</sub>O<sub>2</sub> in the presence of acetonitrile. LDH materials were prepared by the standard method of co-precipitation at constant pH 10, using an aqueous solution of the corresponding metal nitrates and a basic solution containing NaOH and Na<sub>2</sub>CO<sub>3</sub>. The fresh LDHs were calcined to yield the corresponding mixed oxides and then the recovery of the LDH structure by hydration of the mixed oxides was performed. The resulting samples were characterized by AAS, XRD, DRIFT, DR-UV–Vis, BET and determination of basic sites. The results of the catalytic tests for olefin epoxidation were well correlated with the basicity of the samples, which was in turn related to the M<sup>2+</sup>/Al<sup>3+</sup> ratio and the electronegativity of different bivalent metals in the brucite-type layer. |
| first_indexed | 2024-03-09T22:22:08Z |
| format | Article |
| id | doaj.art-63b06750f4d04417978b1b82a8bd6207 |
| institution | Directory Open Access Journal |
| issn | 2073-4344 |
| language | English |
| last_indexed | 2024-03-09T22:22:08Z |
| publishDate | 2022-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Catalysts |
| spelling | doaj.art-63b06750f4d04417978b1b82a8bd62072023-11-23T19:11:59ZengMDPI AGCatalysts2073-43442022-01-0112214510.3390/catal12020145Green Epoxidation of Olefins with Zn<sub>x</sub>Al/Mg<sub>x</sub>Al-LDH Compounds: Influence of the Chemical CompositionRodica Zăvoianu0Anca Cruceanu1Octavian Dumitru Pavel2Corina Bradu3Mihaela Florea4Ruxandra Bîrjega5Faculty of Chemistry, University of Bucharest, 4-12 Regina Elisabeta Blv., 030018 Bucharest, RomaniaFaculty of Chemistry, University of Bucharest, 4-12 Regina Elisabeta Blv., 030018 Bucharest, RomaniaFaculty of Chemistry, University of Bucharest, 4-12 Regina Elisabeta Blv., 030018 Bucharest, RomaniaFaculty of Biology, University of Bucharest, 91-95 Splaiul Independenţei, 050095 Bucharest, RomaniaNational Institute of Materials Physics, 405A Atomistilor Street, 077125 Magurele, RomaniaNational Institute for Lasers, Plasma and Radiation Physics, 077125 Magurele, RomaniaThis contribution concerns the effect of the chemical composition of the brucite-type layer of bi-cationic LDH materials Zn<sub>x</sub>Al and Mg<sub>x</sub>Al (x = 2–5) and tri-cationic LDH Mg<sub>y</sub>Zn<sub>z</sub>Al (y + z = 4, y = 1, 2, 3) on their catalytic activity for olefin epoxidation with H<sub>2</sub>O<sub>2</sub> in the presence of acetonitrile. LDH materials were prepared by the standard method of co-precipitation at constant pH 10, using an aqueous solution of the corresponding metal nitrates and a basic solution containing NaOH and Na<sub>2</sub>CO<sub>3</sub>. The fresh LDHs were calcined to yield the corresponding mixed oxides and then the recovery of the LDH structure by hydration of the mixed oxides was performed. The resulting samples were characterized by AAS, XRD, DRIFT, DR-UV–Vis, BET and determination of basic sites. The results of the catalytic tests for olefin epoxidation were well correlated with the basicity of the samples, which was in turn related to the M<sup>2+</sup>/Al<sup>3+</sup> ratio and the electronegativity of different bivalent metals in the brucite-type layer.https://www.mdpi.com/2073-4344/12/2/145layered double hydroxidesbase catalystsoxidationepoxide |
| spellingShingle | Rodica Zăvoianu Anca Cruceanu Octavian Dumitru Pavel Corina Bradu Mihaela Florea Ruxandra Bîrjega Green Epoxidation of Olefins with Zn<sub>x</sub>Al/Mg<sub>x</sub>Al-LDH Compounds: Influence of the Chemical Composition Catalysts layered double hydroxides base catalysts oxidation epoxide |
| title | Green Epoxidation of Olefins with Zn<sub>x</sub>Al/Mg<sub>x</sub>Al-LDH Compounds: Influence of the Chemical Composition |
| title_full | Green Epoxidation of Olefins with Zn<sub>x</sub>Al/Mg<sub>x</sub>Al-LDH Compounds: Influence of the Chemical Composition |
| title_fullStr | Green Epoxidation of Olefins with Zn<sub>x</sub>Al/Mg<sub>x</sub>Al-LDH Compounds: Influence of the Chemical Composition |
| title_full_unstemmed | Green Epoxidation of Olefins with Zn<sub>x</sub>Al/Mg<sub>x</sub>Al-LDH Compounds: Influence of the Chemical Composition |
| title_short | Green Epoxidation of Olefins with Zn<sub>x</sub>Al/Mg<sub>x</sub>Al-LDH Compounds: Influence of the Chemical Composition |
| title_sort | green epoxidation of olefins with zn sub x sub al mg sub x sub al ldh compounds influence of the chemical composition |
| topic | layered double hydroxides base catalysts oxidation epoxide |
| url | https://www.mdpi.com/2073-4344/12/2/145 |
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