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Belskaya OB, Likholobov VA. Mechanochemical Synthesis of Layered Double Hydroxides as a Promising Method for the Preparation of Adsorbents and Catalysts. KINETICS AND CATALYSIS 2022. [DOI: 10.1134/s0023158422060015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
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Catalysts Derived from Nickel-Containing Layered Double Hydroxides for Aqueous-Phase Furfural Hydrogenation. Catalysts 2022. [DOI: 10.3390/catal12060598] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Changes in the structural and textural properties of NiAl-layered double hydroxides (LDHs) (with 2–4 molar ratios of metals) and state of nickel that occur in different steps of the synthesis of nickel catalysts were studied using XRD, thermal analysis, TPR, low-temperature nitrogen adsorption, XANES, EXAFS, and electron microscopy methods. Relations between nickel content, catalyst reduction conditions, state of nickel, and its catalytic properties were revealed. It was shown that the use of NiAl LDH as the catalyst precursor even at a high content of active metal allows for the obtaining of the dispersed particles of supported nickel that are active in the aqueous-phase hydrogenation of furfural. The catalyst activity and conversion of furfural were found to increase with elevation of the catalyst reduction temperature and the corresponding growth of the fraction of reduced nickel. However, a lower reduction temperature (500 °C) makes it possible to form smaller nickel particles with the size of 4–6 nm, and a high Ni content (Ni:Al = 4) can be used to obtain the active Ni@NiAlOx catalyst. Under mild reaction conditions (90 °C, 2.0 MPa), the furfural conversion reached 93%, and furfuryl alcohol was formed with the selectivity of 70%. Under more severe reaction conditions (150 °C, 3.0 MPa), complete conversion of furfural was achieved, and cyclopentanol and tetrahydrofurfuryl alcohol were the main hydrogenation products.
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Alkali-Free Hydrothermally Reconstructed NiAl Layered Double Hydroxides for Catalytic Transesterification. Catalysts 2022. [DOI: 10.3390/catal12030286] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
NiAl layered double hydroxides (LDHs) are promising bifunctional catalysts comprising tunable redox and Lewis acidic sites. However, most studies of NiAl LDH employ alkali hydroxide carbonate precipitants which may contaminate the final LDH catalyst and leach into reaction media. Here, we report an alkali-free route to prepare NixAl LDHs with a composition range x = 1.7 to 4.1 using (NH4)2CO3 and NH4OH as precipitants. Activation of LDHs by calcination–rehydration protocols reveal NixAl LDHs can be reconstructed under mild hydrothermal treatment (110 °C for 12 h), with the degree of reconstruction increasing with Ni content. Catalyst activity for tributyrin transesterification with methanol was found to increase with Ni content and corresponding base site loadings; TOFs also increased, suggesting that base sites in the reconstructed LDH are more effective for transesterification. Hydrothermally reconstructed Ni4.1Al LDH was active for the transesterification of C4–C12 triglycerides with methanol and was stable towards leaching during transesterification.
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On the Reconstruction Peculiarities of Sol–Gel Derived Mg2−xMx/Al1 (M = Ca, Sr, Ba) Layered Double Hydroxides. CRYSTALS 2020. [DOI: 10.3390/cryst10060470] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
In this study, the reconstruction peculiarities of sol–gel derived Mg2−xMx/Al1 (M = Ca, Sr, Ba) layered double hydroxides were investigated. The mixed metal oxides (MMO) were synthesized by two different routes. Firstly, the MMO were obtained directly by heating Mg(M)–Al–O precursor gels at 650 °C, 800 °C, and 950 °C. These MMO were reconstructed to the Mg2−xMx/Al1 (M = Ca, Sr, Ba) layered double hydroxides (LDHs) in water at 50 °C for 6 h (pH 10). Secondly, in this study, the MMO were also obtained by heating reconstructed LDHs at the same temperatures. The synthesized materials were characterized using X-ray powder diffraction (XRD) analysis and scanning electron microscopy (SEM). Nitrogen adsorption by the Brunauer, Emmett, and Teller (BET) and Barrett, Joyner, and Halenda (BJH) methods were used to determine the surface area and pore diameter of differently synthesized alkaline earth metal substituted MMO compounds. It was demonstrated for the first time that the microstructure of reconstructed MMO from sol–gel derived LDHs showed a “memory effect”.
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Photocatalytic Degradation of 2,4-Dichlorophenol on NiAl-Mixed Oxides Derivatives of Activated Layered Double Hydroxides. Top Catal 2020. [DOI: 10.1007/s11244-020-01269-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Belskaya OB, Likholobov VA. Development of Approaches to the Formation of Platinum Sites with Desired Properties Using Layer-Structured Supports. RUSS J GEN CHEM+ 2020. [DOI: 10.1134/s1070363220030263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Belskaya OB, Duplyakin VK, Likholobov VA. The Role of the Stage of Metal Complex Deposition on Support in the Properties Formation of Supported Platinum Catalysts. KINETICS AND CATALYSIS 2020. [DOI: 10.1134/s0023158419060016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Belskaya O, Stepanova L, Gulyaeva T, Erenburg S, Trubina S, Kvashnina K, Nizovskii A, Kalinkin A, Zaikovskii V, Bukhtiyarov V, Likholobov V. Zinc influence on the formation and properties of Pt/Mg(Zn)AlO catalysts synthesized from layered hydroxides. J Catal 2016. [DOI: 10.1016/j.jcat.2016.06.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Belskaya OB, Stepanova LN, Gulyaeva TI, Leont’eva NN, Zaikovskii VI, Salanov AN, Likholobov VA. Synthesis of Mg2+-, Al3+-, and Ga3+-containing layered hydroxides and supported platinum catalysts based thereon. KINETICS AND CATALYSIS 2016. [DOI: 10.1134/s0023158416040029] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Belskaya OB, Stepanova LN, Gulyaeva TI, Golinskii DV, Belyi AS, Likholobov VA. Study of Pt/MgAlO x catalysts in n-decane dehydrogenation. KINETICS AND CATALYSIS 2015. [DOI: 10.1134/s0023158415050018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Structure of oxides prepared by decomposition of layered double Mg–Al and Ni–Al hydroxides. J SOLID STATE CHEM 2015. [DOI: 10.1016/j.jssc.2015.01.022] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Mironenko RM, Belskaya OB, Talsi VP, Likholobov VA. Quadrupolar magic angle spinning NMR spectra fitted using the Pearson IV function. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2014; 63-64:37-41. [PMID: 25454293 DOI: 10.1016/j.ssnmr.2014.10.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 09/27/2014] [Accepted: 10/06/2014] [Indexed: 06/04/2023]
Abstract
The Pearson IV function was used to fit the asymmetric solid-state (27)Al NMR spectra of alumina based catalysts. A high convergence (correlation coefficient is no less than 0.997) between experimental and simulated spectra was achieved. The decomposition of the (27)Al NMR spectra of zinc/aluminum mixed oxides with different Zn/Al molar ratio revealed an increased fraction (6-9%) of pentacoordinated aluminum atoms in these oxides as compared to γ-Al2O3. As the Zn/Al ratio is raised, the fraction of [AlO6] octahedral units decreases, while the fraction of [AlO4] tetrahedra increases.
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Affiliation(s)
- Roman M Mironenko
- Institute of Hydrocarbons Processing, Siberian Branch of Russian Academy of Sciences, Neftezavodskaya st., 54, 644040 Omsk, Russia; Omsk F.M. Dostoevsky State University, pr. Mira, 55a, 644077 Omsk, Russia.
| | - Olga B Belskaya
- Institute of Hydrocarbons Processing, Siberian Branch of Russian Academy of Sciences, Neftezavodskaya st., 54, 644040 Omsk, Russia; Omsk State Technical University, pr. Mira, 11, 644050 Omsk, Russia
| | - Valentin P Talsi
- Institute of Hydrocarbons Processing, Siberian Branch of Russian Academy of Sciences, Neftezavodskaya st., 54, 644040 Omsk, Russia
| | - Vladimir A Likholobov
- Institute of Hydrocarbons Processing, Siberian Branch of Russian Academy of Sciences, Neftezavodskaya st., 54, 644040 Omsk, Russia; Omsk Scientific Centre, Siberian Branch of Russian Academy of Sciences, pr. Marksa, 15, 644024 Omsk, Russia
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