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Malola S, Svelle S, Bleken FL, Swang O. Detailed reaction paths for zeolite dealumination and desilication from density functional calculations. Angew Chem Int Ed Engl 2011; 51:652-5. [PMID: 22147388 DOI: 10.1002/anie.201104462] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Revised: 10/04/2011] [Indexed: 11/05/2022]
Affiliation(s)
- Sami Malola
- inGAP Center for Research-Based Innovation, Department of Chemistry, University of Oslo, P. O. Box 1033 Blindern, 0315 Oslo, Norway
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52
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Detailed Reaction Paths for Zeolite Dealumination and Desilication From Density Functional Calculations. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201104462] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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53
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Eilertsen EA, Bordiga S, Lamberti C, Damin A, Bonino F, Arstad B, Svelle S, Olsbye U, Lillerud KP. Synthesis of Titanium Chabazite: A New Shape Selective Oxidation Catalyst with Small Pore Openings and Application in the Production of Methyl Formate from Methanol. ChemCatChem 2011. [DOI: 10.1002/cctc.201100281] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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54
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Barbera K, Bonino F, Bordiga S, Janssens TV, Beato P. Structure–deactivation relationship for ZSM-5 catalysts governed by framework defects. J Catal 2011. [DOI: 10.1016/j.jcat.2011.03.016] [Citation(s) in RCA: 218] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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55
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Sommer L, Svelle S, Lillerud KP, Stöcker M, Weckhuysen BM, Olsbye U. Optical investigation of the intergrowth structure and accessibility of Brønsted acid sites in etched SSZ-13 zeolite crystals by confocal fluorescence microscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:16510-16516. [PMID: 20496927 DOI: 10.1021/la101454v] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Template decomposition followed by confocal fluorescence microscopy reveals a tetragonal-pyramidal intergrowth of subunits in micrometer-sized nearly cubic SSZ-13 zeolite crystals. In order to accentuate intergrowth boundaries and defect-rich areas within the individual large zeolite crystals, a treatment with an etching NaOH solution is applied. The defective areas are visualized by monitoring the spatial distribution of fluorescent tracer molecules within the individual SSZ-13 crystals by confocal fluorescence microscopy. These fluorescent tracer molecules are formed at the inner and outer crystal surfaces by utilizing the catalytic activity of the zeolite in the oligomerization reaction of styrene derivatives. This approach reveals various types of etching patterns that are an indication for the defectiveness of the studied crystals. We can show that specially one type of crystals, denoted as core-shell type, is highly accessible to the styrene molecules after etching. Despite the large crystal dimensions, the whole core-shell type SSZ-13 crystal is utilized for catalytic reaction. Furthermore, the confocal fluorescence microscopy measurements indicate a nonuniform distribution of the catalytically important Brønsted acid sites underlining the importance of space-resolved measurements.
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Affiliation(s)
- Linn Sommer
- Centre for Materials Science and Nanotechnology, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway
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56
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Lamberti C, Zecchina A, Groppo E, Bordiga S. Probing the surfaces of heterogeneous catalysts by in situ IR spectroscopy. Chem Soc Rev 2010; 39:4951-5001. [PMID: 21038053 DOI: 10.1039/c0cs00117a] [Citation(s) in RCA: 358] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This critical review describes the reactivity of heterogeneous catalysts from the point of view of four simple, but essential for Chemistry, molecules (namely dihydrogen, carbon monoxide, nitrogen monoxide and ethylene) that are considered as probes or as reactants in combination with "in situ" controlled temperature and pressure Infrared spectroscopy. The fundamental properties of H(2), CO, NO and C(2)H(4) are shortly described in order to justify their different behaviour in respect of isolated sites in different environments, extended surfaces, clusters, crystalline or amorphous materials. The description is given by considering some "key studies" and trying to evidence similarities and differences among surfaces and probes (572 references).
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Affiliation(s)
- Carlo Lamberti
- Department of Inorganic, Physical and Materials Chemistry, NIS Centre of Excellence, University of Turin. Via P. Giuria 7, 10125 Torino, Italy
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57
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Silicalite-1 deactivation in vapour phase Beckmann rearrangement of cyclohexanone oxime to caprolactam. Catal Today 2010. [DOI: 10.1016/j.cattod.2010.03.038] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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58
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59
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Agostini G, Lamberti C, Palin L, Milanesio M, Danilina N, Xu B, Janousch M, van Bokhoven JA. In situ XAS and XRPD parametric rietveld refinement to understand dealumination of Y zeolite catalyst. J Am Chem Soc 2010; 132:667-78. [PMID: 20000838 DOI: 10.1021/ja907696h] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Dealumination of NH(4)-Y zeolite during steaming to 873 K was investigated with in situ, time-dependent, synchrotron radiation XRPD and in situ Al K-edge XAS. Water desorption is complete at 450 K, and ammonium decomposition occurs between 500 and 550 K. Only a small fraction of Al(3+) species (5%) leaves the framework during heating from 710 to 873 K; these species occupy site I' inside the sodalite cage. This fraction increases up to 8% in the first 50 min at 873 K and remains constant for the following 70 min isotherm and during the high-temperature part of the cooling experiment. During cooling from 500 to 450 K, the electron density at site I' increases suddenly, corresponding to a fraction of 30-35% of the total Al, confirmed by ex situ (27)Al MAS solid-state NMR. At that temperature, in situ Al K-edge XAS indicates a change in Al coordination of a large fraction of Al, and thermogravimetric (TG) data show the first water molecules start to repopulate the pores. Such molecules drive the dislodgment of most of the Al from the zeolitic framework. Our data indicate that considerable structural collapse caused by steaming does not occur at the highest temperature; however, defects form, which lead to significant migration of framework Al(3+) to extraframework positions, which occurs only as water is able to enter the pores again, that is, at much lower temperature. Contrary to general opinion, these results demonstrate that zeolite dealumination is not primarily a high-temperature process. The standard Rietveld refinement approach failed to identify extraframework Al species. These new results were obtained by adopting the innovative parametric refinement [J. Appl. Crystallogr. 2007, 40, 87]. Treating all of the XRPD patterns collected during the evolution of temperature as one unique data set significantly reduces the overall number of optimized variables and, thus, their relative correlation, and finally results in a more reliable estimate of the optimized parameters. Our results contribute to a better understanding of the phenomena involved on the atomic scale in the preparation of ultrastable Y zeolites (USY). USY are employed in fluid catalytic cracking (FCC), which is the most important conversion process in petroleum refineries to convert the high-boiling hydrocarbon fractions of petroleum crude oils to more valuable products like gasoline and olefinic gases.
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Affiliation(s)
- Giovanni Agostini
- Department of Inorganic, Materials and Physical Chemistry, Torino University, Via P. Giuria 7,10125 Turin, Italy
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60
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Bordiga S, Bonino F, Lillerud KP, Lamberti C. X-ray absorption spectroscopies: useful tools to understand metallorganic frameworks structure and reactivity. Chem Soc Rev 2010; 39:4885-927. [DOI: 10.1039/c0cs00082e] [Citation(s) in RCA: 117] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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61
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MacArio A, Giordano G, Setti L, Parise A, Campelo JM, Marinas JM, Luna D. Study of lipase immobilization on zeolitic support and transesterification reaction in a solvent free-system. BIOCATAL BIOTRANSFOR 2009. [DOI: 10.1080/10242420701444256] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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62
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Yip ACK, Lam FLY, Hu X, Li P, Yuan WK. Study on the Synthesis of Clay-Based Titanium Silicalite-1 Catalytic Composite. Ind Eng Chem Res 2009. [DOI: 10.1021/ie9002798] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alex C. K. Yip
- Department of Chemical and Biomolecular Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, and State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Frank L. Y. Lam
- Department of Chemical and Biomolecular Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, and State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Xijun Hu
- Department of Chemical and Biomolecular Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, and State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Ping Li
- Department of Chemical and Biomolecular Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, and State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Wei-Kang Yuan
- Department of Chemical and Biomolecular Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, and State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
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63
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Rimola A, Civalleri B, Ugliengo P. Neutral vs zwitterionic glycine forms at the water/silica interface: structure, energies, and vibrational features from B3LYP periodic simulations. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:14027-14034. [PMID: 19360956 DOI: 10.1021/la8029352] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
B3LYP periodic calculations with a triple-xi-polarized Gaussian basis set have been used to study adsorption of glycine on a hydroxylated silica surface (2.2 OH/nm2) model derived from the (001) surface of edingtonite. The simulation envisages glycine adsorbed either as a gas-phase molecule or when microsolvated by up to five H20 molecules. Both neutral and zwitterionic forms of glycine have been considered and their structural, energetic, and spectroscopic vibrational features compared internally and with experiments. As a gas phase glycine sticks in its neutral form at the silica surface, the zwitterion being highly unstable and with transition-state character. When glycine is microsolvated at the silica interface, two H20 molecules render the zwitterion population comparable to that of the neutral form whereas with four H2O molecules the neutral glycine population is wiped out in favor of the zwitterion. With four H20 molecules the most stable structure shows no direct contact between glycine and the silica surface, H20 acting as a mediator via H-bond interactions. The B3LYP energies and structural data were also supported by comparing the scaled harmonic vibrational features with literature FTIR data of glycine adsorbed on an amorphous silica surface either from the gas phase or in water solution.
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Affiliation(s)
- Albert Rimola
- Dipartimento di Chimica IFM and Nanostructured Interfaces and Surfaces, Centre of Excellence and INSTM (Materials Science and Technology) National Consortium, Università di Torino, Via P. Giuria 7, 10125 Torino, Italy
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64
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Macario A, Moliner M, Diaz U, Jorda J, Corma A, Giordano G. Biodiesel production by immobilized lipase on zeolites and related materials. ZEOLITES AND RELATED MATERIALS: TRENDS, TARGETS AND CHALLENGES, PROCEEDINGS OF THE 4TH INTERNATIONAL FEZA CONFERENCE 2008. [DOI: 10.1016/s0167-2991(08)80061-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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65
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Bordiga S, Bonino F, Damin A, Lamberti C. Reactivity of Ti(iv) species hosted in TS-1 towards H2O2–H2O solutions investigated by ab initio cluster and periodic approaches combined with experimental XANES and EXAFS data: a review and new highlights. Phys Chem Chem Phys 2007; 9:4854-78. [PMID: 17912416 DOI: 10.1039/b706637f] [Citation(s) in RCA: 174] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This work is intended to underline how the most-advanced experimental and theoretical physical chemistry tools must be used synergistically to understand the reactivity of Ti-silicalite-1 (TS-1) in an important number of low-temperature oxidation reactions with aqueous H(2)O(2) as the oxidant. Literature results are carefully reviewed and accompanied with new, unpublished highlights of both experimental and computational origin. The first part of this work is devoted to a discussion of the defective nature of the material and to the synergic role played by Si vacancies and Ti insertion in the framework. A summary of the experimental Ti-K-edge EXAFS and XANES literature concerning the activated material in vacuo conditions is then presented and compared to the corresponding Ti geometries obtained by ab initio calculations. From such a comparison, the excellent agreement between experiment and theory is evident. A very good agreement is also obtained for the interaction with water and ammonia. For both H(2)O and NH(3), the agreement is due to the possibility to perform experiments in which the probe molecule is dosed from the gas phase, thus allowing to reach the 1 : 1 (or 1 : 2) ratio between the adsorbing Ti sites and the adsorbed molecule. Then, interaction with hydrogen peroxide is discussed, underlining the problems faced in reaching a common view between experimental and theoretical results, owing to the difficulties both in performing experiments where anhydrous H(2)O(2) is dosed on TS-1, and in taking into account the role played by the aqueous medium in the reactivity of Ti(iv) centres toward H(2)O(2) using ab initio calculations. Only once such difficulties have been overcome, by increasing the complexities of both experiments and ab initio models, is a joint-view finally obtained. Where needed, comparison with other experimental results (X-ray and neutron diffraction, NMR, IR, Raman, UV-vis and resonant Raman) is made.
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Affiliation(s)
- Silvia Bordiga
- Department of Inorganic, Physical and Materials Chemistry and NIS Centre of Excellence, Università di Torino, Via P. Giuria 7, 10125, Torino, Italy
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66
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67
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Structural incorporation of carbon and nitrogen into B-SSZ-13: a spectroscopic and computational studies. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/s0167-2991(07)80894-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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68
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Bu Y, Wang Y, Zhang Y, Wang L, Mi Z, Wu W, Min E, Fu S. Influences of ethylenediamine treatment of Silicalite-1 on the catalytic vapor-phase Beckmann rearrangement of cyclohexanone oxime. CATAL COMMUN 2007. [DOI: 10.1016/j.catcom.2006.05.057] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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69
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Zecchina A, Bordiga S, Vitillo JG, Ricchiardi G, Lamberti C, Spoto G, Bjørgen M, Lillerud KP. Liquid Hydrogen in Protonic Chabazite. J Am Chem Soc 2005; 127:6361-6. [PMID: 15853343 DOI: 10.1021/ja050276c] [Citation(s) in RCA: 190] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Due to its fully reversible nature, H(2) storage by molecular adsorption could represent an advantage with respect to dissociative processes, where kinetic effects during the charging and discharging processes are present. A drawback of this strategy is represented by the extremely weak interactions that require low temperature and high pressure. High surface area materials hosting polarizing sites can represent a viable way toward more favorable working conditions. Of these, in this contribution, we have studied hydrogen adsorption in a series of zeolites using volumetric techniques and infrared spectroscopy at 15 K. We have found that in H-SSZ-13 zeolite the cooperative role played by high surface area, internal wall topology, and presence of high binding energy sites (protons) allows hydrogen to densify inside the nanopores at favorable temperature and pressure conditions.
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Affiliation(s)
- Adriano Zecchina
- Dipartimento di Chimica IFM and NIS Centre of Excellence, Via P. Giuria 7, I-10125 Torino, Italy
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70
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Bordiga S, Regli L, Lamberti C, Zecchina A, Bjørgen M, Lillerud KP. FTIR Adsorption Studies of H2O and CH3OH in the Isostructural H-SSZ-13 and H-SAPO-34: Formation of H-Bonded Adducts and Protonated Clusters. J Phys Chem B 2005; 109:7724-32. [PMID: 16851897 DOI: 10.1021/jp044324b] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The acidity of the isostructural H-SSZ-13 and H-SAPO-34 has been investigated by transmission FTIR spectroscopy using H2O and CH3OH as molecular probes. Interactions between the zeolitic samples and the probe molecules led to perturbations and proton transfers directly related to the acidity of the materials. The entire set of acidic sites in H-SSZ-13 interacts with H2O and CH3OH to give H-bonded adducts or protonated species. H3O+ is not formed in appreciable amounts upon H2O adsorption on H-SSZ-13, but at high coverages H2O generates clusters that have a proton affinity sufficiently high to abstract protons from the zeolite framework. Parallel experiments carried out for H-SAPO-34 showed that the H2O clusters abstract protons from Brønsted sites only to a minor extent. Moving to CH3OH, even if it has a higher proton affinity than H2O and should expectingly experience an easier protonation, proton transfer is totally absent in H-SAPO-34 under our set of conditions. The clear evidence of methanol protonation in H-SSZ-13 definitely states the strong acidic character of this material. When irreversibly adsorbed CH3OH is present in H-SSZ-13, an appreciable amount of (CH3)2O is formed upon heating to 573 K. Compared to its SAPO analogue, the present set of data indisputably points to H-SSZ-13 as the strongest Brønsted acidic material.
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Affiliation(s)
- Silvia Bordiga
- Dipartimento di Chimica IFM and NIS Centre of Excellence, Via P. Giuria 7, I-10125 Torino, Italy
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71
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Bordiga S, Regli L, Cocina D, Lamberti C, Bjørgen M, Lillerud KP. Assessing the Acidity of High Silica Chabazite H−SSZ-13 by FTIR Using CO as Molecular Probe: Comparison with H−SAPO-34. J Phys Chem B 2005; 109:2779-84. [PMID: 16851287 DOI: 10.1021/jp045498w] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Zeolitic materials based on the chabazite topology, such as H-SAPO-34, possess unique shape-selectivity properties for converting methanol into light olefins. In addition to the topology, zeolite acidity is inherently linked to catalyst activity and selectivity. The acidic properties of high silica chabazite (H-SSZ-13) have attracted much attention in the past decade because the material represents an idealized model system having one acidic site per cage. Conclusions drawn so far have essentially been founded on quantum chemical methods. An experimentally based benchmark of the acidity of H-SSZ-13 has hitherto not been available. In this work, transmission FTIR spectroscopy provides a description of the different acidic sites of H-SSZ-13 by using CO as molecular probe at 70 K. The results demonstrate that H-SSZ-13 is a strongly Brønsted acidic material, essentially having two distinct families of acidic sites. In contrast to numerous preceding reports, we find it fundamental to consider proton distributions among all four possible sites, and do not delimit the interpretations to only two sites. The present data consistently suggest the most abundant family of protons to have three members being located on different crystalline positions on the eight-membered-ring window giving access to the chabazite cage. Consequently, these protons are exposed to two neighboring cages. The second, and less abundant family, is constituted by only one site that is situated on the six-membered ring defining the top/bottom of the barrel-shaped chabazite cage. This proton is therefore only exposed to one cage and requires a higher CO pressure to form adducts. Toward CO, both families of sites possess the same acidity. Parallel experiments were also carried out for the isostructural and commercially important H-SAPO-34 having an equal density of acidic sites. This is the first attempt to directly compare, on an experimental basis, the acidity of these two materials.
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Affiliation(s)
- Silvia Bordiga
- Dipartimento di Chimica IFM and NIS Centre of Excellence, Via P. Giuria 7, I-10125 Torino, Italy
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72
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Groppo E, Lamberti C, Bordiga S, Spoto G, Zecchina A. The Structure of Active Centers and the Ethylene Polymerization Mechanism on the Cr/SiO2 Catalyst: A Frontier for the Characterization Methods. Chem Rev 2005; 105:115-84. [PMID: 15720153 DOI: 10.1021/cr040083s] [Citation(s) in RCA: 354] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- E Groppo
- Department of Inorganic, Physical and Materials Chemistry and NIS Centre of Excellence, University of Torino, Via P. Giuria 7, 10125 Torino, Italy
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73
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Zecchina A, Spoto G, Bordiga S. Probing the acid sites in confined spaces of microporous materials by vibrational spectroscopy. Phys Chem Chem Phys 2005; 7:1627-42. [DOI: 10.1039/b418763f] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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74
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Ab initio vibrational spectroscopy of molecular adsorbates in mordenite. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/s0167-2991(05)80390-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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75
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Regli L, Zecchina A, Vitillo JG, Cocina D, Spoto G, Lamberti C, Lillerud KP, Olsbye U, Bordiga S. Hydrogen storage in Chabazite zeolite frameworks. Phys Chem Chem Phys 2005; 7:3197-203. [PMID: 16240032 DOI: 10.1039/b509124a] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have recently highlighted that H-SSZ-13, a highly siliceous zeolite (Si/Al = 11.6) with a chabazitic framework, is the most efficient zeolitic material for hydrogen storage [A. Zecchina, S. Bordiga, J. G. Vitillo, G. Ricchiardi, C. Lamberti, G. Spoto, M. Bjørgen and K. P. Lillerud, J. Am. Chem. Soc., 2005, 127, 6361]. The aim of this new study is thus to clarify both the role played by the acidic strength and by the density of the polarizing centers hosted in the same framework topology in the increase of the adsorptive capabilities of the chabazitic materials towards H2. To achieve this goal, the volumetric experiments of H2 uptake (performed at 77 K) and the transmission IR experiment of H2 adsorption at 15 K have been performed on H-SSZ-13, H-SAPO-34 (the isostructural silico-aluminophosphate material with the same Brønsted site density) and H-CHA (the standard chabazite zeolite: Si/Al = 2.1) materials. We have found that a H2 uptake improvement has been obtained by increasing the acidic strength of the Brønsted sites (moving from H-SAPO-34 to H-SSZ-13). Conversely, the important increase of the Brønsted sites density (moving from H-SSZ-13 to H-CHA) has played a negative role. This unexpected behavior has been explained as follows. The additional Brønsted sites are in mutual interaction via H-bonds inside the small cages of the chabazitic framework and for most of them the energetic cost needed to displace the adjacent OH ligand is higher than the adsorption enthalpy of the OH...H2 adduct. From our work it can be concluded that proton exchanged chabazitic frameworks represent, among zeolites, the most efficient materials for hydrogen storage. We have shown that a proper balance between available space (volume accessible to hydrogen), high contact surface, and specific interaction with strong and isolated polarizing centers are the necessary characteristics requested to design better materials for molecular H2 storage.
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Affiliation(s)
- Laura Regli
- Dipartimento di Chimica IFM and NIS Centre of Excellence, Via P. Giuria 7, I-10125 Torino, Italy
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76
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Molecular spectroscopic study of the fine structure of aluminum deficient, hydrophobic zeolites. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/s0167-2991(05)80396-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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77
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Zhanpeisov NU, Anpo M. Hydrogen bonding versus coordination of adsorbate molecules on Ti-silicalites: a density functional theory study. J Am Chem Soc 2004; 126:9439-44. [PMID: 15281837 DOI: 10.1021/ja0385484] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The present study discusses the results of theoretical calculations obtained at the B3LYP/ 6-31G level on the structural, electronic, and energetic properties of Ti-silicalites. Particularly, the relevance of 5T cluster models, either H- or OH-terminated, in large-scale calculations has been critically considered. It was shown that an open surface structure with one OH group and a closed-bulk structure with no bonded OH group at the Ti site are responsible for the observed UV-vis properties of Ti-silicalite materials. Both water and methanol can preferably interact with Ti-silicalites through the H-bonding mechanism, while ammonia can form either H-bonded or coordination complexes. The calculations support the existence of highly dispersed Ti sites in a tetrahedral environment only in Ti-silicalites because an increase in the coordination number of the Ti site by next-neighbor lattice oxygens is the energetically less favorable process.
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Affiliation(s)
- Nurbosyn U Zhanpeisov
- Department of Applied Chemistry, Osaka Prefecture University, 1-1 Gakuen-cho, Sakai, Osaka 599-8531, Japan.
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78
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Bjørgen M, Bonino F, Kolboe S, Lillerud KP, Zecchina A, Bordiga S. Spectroscopic evidence for a persistent benzenium cation in zeolite H-beta. J Am Chem Soc 2004; 125:15863-8. [PMID: 14677978 DOI: 10.1021/ja037073d] [Citation(s) in RCA: 156] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Experimental evidence of protonation of an aromatic ring by a zeolite is hereby presented for the first time. The changes in vibrational properties and electronic transitions of the highest polymethylbenzene homologue, that is, hexamethylbenzene, were investigated after introducing the compound directly into a H-beta zeolite. Protonation of the aromatic ring, and thus the loss of symmetry, activated a vibrational ring mode at 1600 cm(-)(1). Furthermore, an electronic transition around 26 000 cm(-)(1), which was totally absent for the neutral species, was an obvious consequence of protonation. A parallel study of hexamethylbenzene adsorbed on a beta zeolite virtually free from protons did not show those distinctive spectral features. On the basis of the gas-phase proton affinity of hexamethylbenzene, a complete proton transfer from the zeolite framework to the molecule is, according to conventional considerations, not expected. The hexamethylbenzenium ion is stable in the zeolite cavities at least up to 200 degrees C. The remarkable persistence of this carbenium ion may be attributed to spatial constraints imposed by the tight fit of the cation inside the zeolite channels. Hexamethylbenzene is a relevant reaction intermediate in the methanol-to-hydrocarbons reaction and also plays a central role as a coke precursor in zeolite-catalyzed reactions that involve polymethylbenzenes.
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Affiliation(s)
- Morten Bjørgen
- Department of Chemistry, University of Oslo, P.O. Box 1033, N-0315 Oslo, Norway
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79
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Bonino F, Damin A, Ricchiardi G, Ricci M, Spanò G, D'Aloisio R, Zecchina A, Lamberti C, Prestipino C, Bordiga S. Ti-Peroxo Species in the TS-1/H2O2/H2O System. J Phys Chem B 2004. [DOI: 10.1021/jp036166e] [Citation(s) in RCA: 180] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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80
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Milanesio M, Artioli G, Gualtieri AF, Palin L, Lamberti C. Template burning inside TS-1 and Fe-MFI molecular sieves: an in situ XRPD study. J Am Chem Soc 2004; 125:14549-58. [PMID: 14624604 DOI: 10.1021/ja037229+] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The high X-ray flux available at the European Synchrotron Radiation Facility (ESRF), combined with the use of a suitably designed area detector setup, allowed us to follow in real time the structural changes occurring during the template burning processes inside TS-1 and Fe-silicalite MFI zeolites with a X-ray powder diffraction technique (XRPD). Rietveld analysis of the XRPD patterns collected in the 350-1000 K interval, integrated each 15 K, yields to the determination of the template overall occupancy factor versus T with an accuracy comparable with that obtained by thermogravimetric measurements, routinely employed for this purpose. The evolution of the structural parameters (V, a, b, c, site occupancy factor of the template molecule) vs T has been obtained. These data allow us to have, for the first time, a complete view of the structural rearrangements induced by the template burning process on the zeolitic framework. The differences caused by the different heteroatom inserted in the MFI lattice (Ti or Fe) are discussed. For both TS-1 and Fe-MFI, the kinetics of the reaction were investigated, to obtain the activation energy of the calcinations process employing the nonisothermal data according to the theory recently proposed by Kennedy and Clark [Thermochim. Acta, 1997, 307, 27-35]. For TS-1 only, the time-resolved template burning experiment has been repeated in isothermal conditions at four different temperatures, to obtain the activation energy from isothermal data, according to the standard procedure. Comparison between Arrhenius plots obtained from isothermal and nonisothermal data demonstrates that the Kennedy and Clark method can be also applied to complex materials such as the MFI zeolites. This approach, when applied to time-resolved XRPD studies, is much less time consuming (requesting, in principle, one single nonisothermal run) with respect to the classic approach, which requests at least three isothermal runs. Moreover, it allows a remarkably lower associated error (151 +/- 11 versus 146 +/- 30 kJ mol(-)(1)) due to the much higher number of experimental points employed to perform the linear fit.
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Affiliation(s)
- Marco Milanesio
- Dipartimento di Scienze e Tecnologie Avanzate, Università del Piemonte Orientale A. Avogadro, Corso T. Borsalino 54, I-15100 Alessandria, Italy
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81
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Forni L, Fornasari G, Giordano G, Lucarelli C, Katovic A, Trifirò F, Perri C, Nagy JB. Vapor phase Beckmann rearrangement using high silica zeolite catalyst. Phys Chem Chem Phys 2004. [DOI: 10.1039/b316810g] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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82
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Bučko T, Benco L, Hafner J. Defect sites at the (001) surface of mordenite: Anab initiostudy. J Chem Phys 2003. [DOI: 10.1063/1.1565321] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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83
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Palin L, Lamberti C, Kvick Å, Testa F, Aiello R, Milanesio M, Viterbo D. Single-Crystal Synchrotron Radiation X-ray Diffraction Study of B and Ga Silicalites Compared to a Purely Siliceous MFI: A Discussion of the Heteroatom Distribution. J Phys Chem B 2003. [DOI: 10.1021/jp027586r] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - Å. Kvick
- ESRF, BP 220, F-38043 Grenoble Cedex, France
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84
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Pascale F, Ugliengo P, Civalleri B, Orlando R, D’Arco P, Dovesi R. Hydrogarnet defect in chabazite and sodalite zeolites: A periodic Hartree–Fock and B3-LYP study. J Chem Phys 2002. [DOI: 10.1063/1.1499477] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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85
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Bordiga S, Damin A, Bonino F, Zecchina A, Spanò G, Rivetti F, Bolis V, Prestipino C, Lamberti C. Effect of Interaction with H2O and NH3 on the Vibrational, Electronic, and Energetic Peculiarities of Ti(IV) Centers TS-1 Catalysts: A Spectroscopic and Computational Study. J Phys Chem B 2002. [DOI: 10.1021/jp026106t] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | | | | | | | - Vera Bolis
- Dipartimento di Scienze Chimiche, Alimentari, Farmaceutiche e Farmacologiche, Università del Piemonte Orientale “A. Avogadro”, Via Bovio 6, 28100 Novara, Italy
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86
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Damin A, Bordiga S, Zecchina A, Lamberti C. Reactivity of Ti(IV) sites in Ti-zeolites: An embedded cluster approach. J Chem Phys 2002. [DOI: 10.1063/1.1481378] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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87
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Damin A, Bonino F, Ricchiardi G, Bordiga S, Zecchina A, Lamberti C. Effect of NH3 Adsorption on the Structural and Vibrational Properties of TS-1. J Phys Chem B 2002. [DOI: 10.1021/jp0257698] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alessandro Damin
- Department of Inorganic, Physical and Material Chemistry, University of Turin, Via P. Giuria 7, I-10125 Torino Italy, and INFM UdR di Torino Università
| | - Francesca Bonino
- Department of Inorganic, Physical and Material Chemistry, University of Turin, Via P. Giuria 7, I-10125 Torino Italy, and INFM UdR di Torino Università
| | - Gabriele Ricchiardi
- Department of Inorganic, Physical and Material Chemistry, University of Turin, Via P. Giuria 7, I-10125 Torino Italy, and INFM UdR di Torino Università
| | - Silvia Bordiga
- Department of Inorganic, Physical and Material Chemistry, University of Turin, Via P. Giuria 7, I-10125 Torino Italy, and INFM UdR di Torino Università
| | - Adriano Zecchina
- Department of Inorganic, Physical and Material Chemistry, University of Turin, Via P. Giuria 7, I-10125 Torino Italy, and INFM UdR di Torino Università
| | - Carlo Lamberti
- Department of Inorganic, Physical and Material Chemistry, University of Turin, Via P. Giuria 7, I-10125 Torino Italy, and INFM UdR di Torino Università
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88
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Sokol AA, Catlow CRA, Garcés JM, Kuperman A. Local States in Microporous Silica and Aluminum Silicate Materials. 1. Modeling Structure, Formation, and Transformation of Common Hydrogen Containing Defects. J Phys Chem B 2002. [DOI: 10.1021/jp0133384] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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89
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90
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91
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Ricchiardi G, Damin A, Bordiga S, Lamberti C, Spanò G, Rivetti F, Zecchina A. Vibrational structure of titanium silicate catalysts. A spectroscopic and theoretical study. J Am Chem Soc 2001; 123:11409-19. [PMID: 11707118 DOI: 10.1021/ja010607v] [Citation(s) in RCA: 324] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A thorough analysis of the vibrational features of the titanium silicalite-1 (TS-1) catalyst is presented, based on quantitative IR measurements, Raman and resonant Raman experiments, quantitative XANES, and quantum chemical calculations on cluster and periodic models. The linear correlation of the intensity of the IR and Raman bands located at 960 and 1125 cm(-1) and the XANES peak at 4967 eV with the amount of tetrahedral Ti are quantitatively demonstrated. Raman and resonant Raman spectra of silicalite and TS-1 with variable Ti content are presented, showing main features at 960 and 1125 cm(-1) associated with titanium insertion into the zeolite framework. The enhancement of the intensity of the 1125 cm(-1) feature and the invariance of the 960 cm(-1) feature in UV-Raman experiments, are discussed in terms of resonant Raman selection rules. Quantum chemical calculations on cluster models Si[OSi(OH)(3)](4) and Ti[OSi(OH)(3)](4) at the B3LYP/6-31G(d) level of theory provide the basis for the assignment of the main vibrational contributions and for the understanding of Raman enhancement. The resonance-enhanced 1125 cm(-1) mode is unambiguously associated with a totally symmetric vibration of the TiO(4) tetrahedron, achieved through in-phase antisymmetric stretching of the four connected Ti-O-Si bridges. This vibration can also be described as a totally symmetric stretching of the four Si-O bonds pointing toward Ti. The resonance enhancement of this feature is explained in terms of the electronic structure of the Ti-containing moiety. Asymmetric stretching modes of TO(4) units show distinct behavior when (i) T is occupied by Si as in perfect silicalite, (ii) T is occupied by Ti as in TS-1, or (iii) the oxygen atom belongs to an OH group, such as in terminal tetrahedra of cluster models and in real defective zeolites. Asymmetric SiO(4) and TiO(4) stretching modes appear above and below 1000 cm(-1), respectively, when they are achieved through antisymmetric stretching of the T-O-Si bridges, and around 800 cm(-1) (in both SiO(4) and TiO(4)) when they involve symmetric stretching of the T-O-Si units. In purely siliceous models, the transparency gap between the main peaks at 800 and 1100 cm(-1) contains only vibrational features associated with terminal Si-OH groups, while in Ti-containing models it contains also the above-mentioned asymmetric TiO(4) modes, which in turn are strongly coupled with Si-OH stretching modes. Calculations on periodic models of silicalite and TS-1 free of OH groups using the QMPOT embedding method correctly reproduce the transparency gap of silicalite and the appearance of asymmetric TiO(4) vibrations at 960 cm(-1) in TS-1. Finally, we demonstrate, for the first time, that the distortion of the tetrahedral symmetry around Ti caused by water adsorption quenches the UV-Raman enhancement of the 1125 cm(-1) band.
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Affiliation(s)
- G Ricchiardi
- Dipartimento di Chimica, IFM Università di Torino, Via P. Giuria 7, 10125 Turin, Italy.
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92
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The Role of Isolated Sites in Heterogeneous Catalysis: Characterization and Modeling. Int J Mol Sci 2001. [DOI: 10.3390/i2050167] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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