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Catalysis on Zeolites and Zeolite-Like Materials II
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Catalysis on Zeolites and Zeolite-Like Materials II

A special issue of Catalysts (ISSN 2073-4344). This special issue belongs to the section "Catalytic Materials".

Deadline for manuscript submissions: closed (10 April 2023) | Viewed by 23941

Special Issue Editor

Prof. Dr. Wladimir Reschetilowski

E-Mail Website
Guest Editor
Fakultät Chemie und Lebensmittelchemie, Technische Universität Dresden, Helmholtzstraße 14, 01069 Dresden, Germany
Interests: heterogeneous catalysis; zeolites; micro/mesoporous aluminosilicates; microreactor systems; flow chemistry; green chemistry
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

This Special Issue is a continuation of the previous successful Special Issue, “Catalysis on Zeolites and Zeolite-Like Materials”.

The regular pore system of zeolites, with cavities and nanometric channels, as well as the resulting characteristic properties, predestine them for wide use as catalysts in chemical technology. Over the past several decades, progress in zeolite synthesis enabled the discovery of new zeolite types, which allowed for the development of new catalytic processes in petrochemical industries. Moreover, new tools for zeolite modification have allowed for additional applications of zeolite-based catalysts in the field of environmental catalysis. The development of new mesoporous and micro/mesoporous or zeolite-like materials (e.g., metal–organic frameworks), as well as progress in computational chemistry and solid-state characterization techniques, demonstrated that the potential of ordered pore materials is still far from exhausted, and that further biocatalysis, electrocatalysis, photocatalysis, and micro/nanostructure technology indicate increasing interest in this class of substances.

With great pleasure, I invite you to submit your manuscript to the Special Issue “Catalysis on Zeolites and Zeolite-Like Materials II”, to share developments and recent progress regarding the synthesis, characterization and application of zeolites or zeolite-like materials as catalysts.

Prof. Dr. Wladimir Reschetilowski
Guest Editor

Manuscript Submission Information

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Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Catalysts is an international peer-reviewed open access monthly journal published by MDPI.

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Keywords

  • zeolites and zeolite-like materials
  • acid-base catalysis
  • bifunctional catalysis
  • environmental catalysis
  • biocatalysis
  • electrocatalysis
  • photocatalysis
  • C1 chemistry
  • kinetic modelling of zeolite-catalyzed chemical reactions
  • computation in catalysis with ordered porous materials

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Published Papers (12 papers)

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Editorial

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4 pages, 156 KiB  
Editorial
Catalysis on Zeolites and Zeolite-like Materials II
by Wladimir Reschetilowski
Catalysts 2024, 14(7), 460; https://doi.org/10.3390/catal14070460 - 17 Jul 2024
Viewed by 721
Abstract
This Special Issue is a continuation of the previous successful Special Issue, “Catalysis on Zeolites and Zeolite-Like Materials”, which presented the latest developments and advances in the synthesis, characterization, and application of zeolites and zeolite-like materials as catalysts by renowned scientists [...] Full article
(This article belongs to the Special Issue Catalysis on Zeolites and Zeolite-Like Materials II)

Research

Jump to: Editorial

20 pages, 9272 KiB  
Article
Increasing Al-Pair Abundance in SSZ-13 Zeolite via Zeolite Synthesis in the Presence of Alkaline Earth Metal Hydroxide Produces Hydrothermally Stable Co-, Cu- and Pd-SSZ-13 Materials
by Konstantin Khivantsev, Miroslaw A. Derewinski, Libor Kovarik, Mark Bowden, Xiaohong Shari Li, Nicholas R. Jaegers, Daria Boglaienko, Xavier I. Pereira-Hernandez, Carolyn Pearce, Yong Wang and Janos Szanyi
Catalysts 2024, 14(1), 56; https://doi.org/10.3390/catal14010056 - 12 Jan 2024
Cited by 1 | Viewed by 1949
Abstract
Replacing alkaline for alkaline-earth metal hydroxide in the synthesis gel during the synthesis of siliceous SSZ-13 zeolite (Si/Al~10) yields SSZ-13 with novel, advantageous properties. Its NH4-form ion-exchanges higher amount of isolated divalent M(II) ions than the conventional one: this is the [...] Read more.
Replacing alkaline for alkaline-earth metal hydroxide in the synthesis gel during the synthesis of siliceous SSZ-13 zeolite (Si/Al~10) yields SSZ-13 with novel, advantageous properties. Its NH4-form ion-exchanges higher amount of isolated divalent M(II) ions than the conventional one: this is the consequence of an increased number of Al pairs in the structure induced by the +2 charge of Sr(II) cations in the synthesis gel that force two charge-compensating AlO4− motives to reside closer together. We characterize the +2 state of Co(II) ions in these materials with infra-red spectroscopy and X-ray absorption spectroscopy measurements and show their utility for NOx pollutant adsorption from ambient air: the ones derived from SSZ-13 with higher Al pair content contain more isolated cobalt(II) and, thus, perform better as ambient-air NOx adsorbers. Notably, Co(II)/SSZ-13 with an increased number of Al pairs is significantly more hydrothermally stable than its NaOH-derived analogue. Loading Pd(II) into Co-SSZ-13(Sr) produces an active NOx adsorber (PNA) material that can be used for NOx adsorption from simulated diesel engine exhaust. The critical issue for these applications is hydrothermal stability of Pd-zeolites. Pd/SSZ-13 synthesized in the presence of Sr(OH)2 does not lose its PNA capacity after extremely harsh aging at 850 and 900 °C (10 h in 10% H2O/air flow) and loses only ~55% capacity after hydrothermal aging at 930 °C. This can be extended to other divalent metals for catalytic applications, such as copper: we show that Cu/SSZ-13 catalyst can survive hydrothermal aging at 920 °C without losing its catalytic properties, metal dispersion and crystalline structure. Thus, we provide a new, simple, and scalable strategy for making remarkably (hydro)thermally stable metal-zeolite materials/catalysts with a number of useful applications. Full article
(This article belongs to the Special Issue Catalysis on Zeolites and Zeolite-Like Materials II)
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16 pages, 2361 KiB  
Article
The Investigation of Zeolite to Matrix Ratio Effect on the Performance of FCC Catalysts during Catalytic Cracking of Hydrotreated VGO
by Adeel Ahmad, Shakeel Ahmed, Mohammed Abdul Bari Siddiqui and Abdallah A. Al-Shammari
Catalysts 2023, 13(9), 1255; https://doi.org/10.3390/catal13091255 - 30 Aug 2023
Cited by 3 | Viewed by 1737
Abstract
Fluidized catalytic cracking of vacuum gas oil is considered a promising factor in enhancing the gasoline yield to fulfill global energy demands. In this study, a series of FCC catalysts with a zeolite to matrix ratio varying from 18 to 50 was prepared [...] Read more.
Fluidized catalytic cracking of vacuum gas oil is considered a promising factor in enhancing the gasoline yield to fulfill global energy demands. In this study, a series of FCC catalysts with a zeolite to matrix ratio varying from 18 to 50 was prepared using USY zeolite and amorphous matrix. The matrix was composed of amorphous silica-alumina, kaolin, and silica sol binder. All fresh catalysts were subjected to hydrothermal deactivation treatment at 750 °C for 5 h. The performance evaluation of FCC catalysts was conducted in a fixed bed microactivity test unit, with vacuum gas oil as feed at 550 °C. Comparing a steamed CAT01 sample with a fresh CAT01, the surface area of the steamed sample was 23.3% less. Similarly, the fresh sample CAT05 acidity increased by 102% when compared with the fresh CAT01 sample. As the zeolite to matrix ratio increased, the selectivity of dry gas, LPG, and coke increased, associated with a consistent decrease in gasoline and heavy ends (LCO and HCO). The combined selectivity of product gasoline and LCO with low-zeolite steamed catalyst (CAT01) was 82%, and that of high-zeolite steamed catalyst (CAT05) was 76%. Furthermore, coke selectivity for the steamed CAT01 was 2.1%, whereas 3.7% was observed for the steamed CAT05 sample. The effect of the zeolite to matrix ratio was less pronounced in steamed catalysts as compared with fresh catalysts. Full article
(This article belongs to the Special Issue Catalysis on Zeolites and Zeolite-Like Materials II)
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13 pages, 1336 KiB  
Article
Scale-Up for the Conversion of Corn Stover-Derived Levulinic Acid into 2-Methyltetrahydrofuran
by Eli A. Peske, Ian M. Foerster and Wayne S. Seames
Catalysts 2023, 13(6), 972; https://doi.org/10.3390/catal13060972 - 3 Jun 2023
Cited by 2 | Viewed by 1511
Abstract
Previous research has identified attractive chemical pathways to form levulinic–lactic acid mixtures from corn stover. Unfortunately, there is little market demand for levulinic acid, so conversion into more useful chemicals is needed. Presented herein are the results from a study to translate and [...] Read more.
Previous research has identified attractive chemical pathways to form levulinic–lactic acid mixtures from corn stover. Unfortunately, there is little market demand for levulinic acid, so conversion into more useful chemicals is needed. Presented herein are the results from a study to translate and optimize two lab-scale reactions that can be used to transform levulinic acid into a useful platform chemical, 2-methyltetrahydrofuran (2-MeTHF), to the continuous bench-scale. 2-MeTHF is an important monomer for the production of liquid polyols, which are used in polymer foam products. First, a hydrogenation reaction takes place, transforming levulinic acid into γ-valerolactone (GVL) by reaction with isopropanol using a Zr-β-zeolite catalyst. Next, the GVL is reacted with hydrogen to form 2-MeTHF utilizing a CuO/Al2O3 catalyst. Both reactions were optimized in bench-scale continuous flow reactors designed to produce 0.613 kg/h of 2-MeTHF from an initial feed of 1.02 kg/h of levulinic acid with a single pass conversion of 81 mol%. Full article
(This article belongs to the Special Issue Catalysis on Zeolites and Zeolite-Like Materials II)
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14 pages, 2768 KiB  
Article
A DFT Study on Single Brønsted Acid Sites in Zeolite Beta and Their Interaction with Probe Molecules
by Alexander V. Vorontsov, Panagiotis G. Smirniotis and Umesh Kumar
Catalysts 2023, 13(5), 833; https://doi.org/10.3390/catal13050833 - 2 May 2023
Cited by 1 | Viewed by 1822
Abstract
Zeolites are subjects of intensive research, as they have vast industrial applications. However, exact nature of catalytic active sites remains elusive. With this research, we attempt to shed light on the Brønsted acid sites in zeolite beta modification A and correlate the widely [...] Read more.
Zeolites are subjects of intensive research, as they have vast industrial applications. However, exact nature of catalytic active sites remains elusive. With this research, we attempt to shed light on the Brønsted acid sites in zeolite beta modification A and correlate the widely used TPD methods of their identification with the theoretically determined strongest and weakest acid sites. A diverse set of probe molecules with a wide range of acid strength of their conjugated acids is applied to determine the heats of their adsorption over protonated zeolite beta samples. The molecules studied were acetonitrile, dimethyl sulfide, dimethyl sulfoxide, isothiazole, pyridine, tetrahydrofuran, and ammonia. It was found that the heat of adsorption of the probe molecules correlated with the acid strength of acid sites only partially. Only some of the strong acid sites were able to be identified, while the weakest acid site was often identified correctly. To conclude, the widely used method of zeolites acid sites studies delivers only partially correct results, and the conclusions from such TPD studies should be treated with caution. Full article
(This article belongs to the Special Issue Catalysis on Zeolites and Zeolite-Like Materials II)
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11 pages, 2780 KiB  
Article
Development of Highly Efficient Hydroisodeparaffinization Catalysts Based on Micro-Mesoporous SAPO-31: New Approaches in the Synthesis of SAPO-31 and the Preparation of Bifunctional Catalysts
by Gennady V. Echevsky, Aleksander V. Toktarev, Evgeny G. Kodenev and Dmitry G. Aksenov
Catalysts 2023, 13(5), 810; https://doi.org/10.3390/catal13050810 - 27 Apr 2023
Viewed by 1216
Abstract
A method is proposed for the synthesis of micro-mesoporous SAPO-31 with a high external surface area and large mesopore volume using tetraethoxysilane as a source of silicon. The synthesis of SAPO-31 is based on the principles underlying the Stöber process approach, which allows [...] Read more.
A method is proposed for the synthesis of micro-mesoporous SAPO-31 with a high external surface area and large mesopore volume using tetraethoxysilane as a source of silicon. The synthesis of SAPO-31 is based on the principles underlying the Stöber process approach, which allows control of the pore diameter and volume and, hence, the external surface area of the product material. The use of the proposed methods for depositing the hydro-dehydrogenating component on the synthesized micro-mesoporous SAPO-31 made it possible to obtain highly efficient bifunctional hydroisodeparaffinization catalysts with the platinum or palladium content not higher than 0.2 wt.%. As a result, the process temperature can be decreased by 50–60 °C in comparison with the known analogs. Therewith, for example, in the test reaction of n-decane hydroisodeparaffinization at a temperature of 300 °C and feed rate of 1.5 h−1, the conversion above 90%, and the 97–98% yield of liquid products, the 95% selectivity to isomeric products were achieved. Full article
(This article belongs to the Special Issue Catalysis on Zeolites and Zeolite-Like Materials II)
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18 pages, 8987 KiB  
Article
MFI Type Zeolite Aggregates with Nanosized Particles via a Combination of Spray Drying and Steam-Assisted Crystallization (SAC) Techniques
by Albert G. F. Machoke, Aurina Martinez Arias, Giulia Baracchini, Michael Rubin, Hasan Baser, Tobias Weissenberger, Roland Dittmeyer, Alfred Weber, Martin Hartmann and Wilhelm Schwieger
Catalysts 2023, 13(3), 536; https://doi.org/10.3390/catal13030536 - 7 Mar 2023
Cited by 2 | Viewed by 2271
Abstract
Hydrothermal synthesis is the state-of-the-art technique for the preparation of zeolites and related porous solids. However, when it comes to the preparation of nanosized zeolites, this technique is limited by low yields, separation problems and high amounts of waste. In this work, we [...] Read more.
Hydrothermal synthesis is the state-of-the-art technique for the preparation of zeolites and related porous solids. However, when it comes to the preparation of nanosized zeolites, this technique is limited by low yields, separation problems and high amounts of waste. In this work, we utilized the strengths of a combination of spray drying and steam-assisted crystallization (SAC), also known as dry gel conversion, to reduce these problems. At spray drying temperatures between 300 and 400 °C, it was possible to convert all the amorphous material via SAC into zeolite particles without extra addition of template. Kinetic studies of SAC revealed that about 4 to 8 days are needed to achieve the formation of a 100% crystalline product. The newly formed crystalline phase was crystallized on the surface of the nanosized zeolites and led to a slight increase in the primary particle size while the macroscopic morphology of the spray-dried aggregates was preserved. This work demonstrates that the combination of spray drying and SAC are useful tools in supplementing the hydrothermal synthesis of nanosized zeolites. Full article
(This article belongs to the Special Issue Catalysis on Zeolites and Zeolite-Like Materials II)
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31 pages, 9945 KiB  
Article
Impact of Geometric and Electronic Factors on Selective Hydro-Deoxygenation of Guaiacol by Surface-Rich Metal/Silica Catalysts
by Nils Kretzschmar, Oliver Busse and Markus Seifert
Catalysts 2023, 13(2), 425; https://doi.org/10.3390/catal13020425 - 16 Feb 2023
Cited by 3 | Viewed by 2216
Abstract
The selective production of hydrocarbons for the chemical industry from biogenic feedstock is a significant challenge when ensuring hydrocarbon and fuel supply, despite the heterogeneity of this feed. In this study, guaiacol, as a surrogate for complex lignin-based biomass resources, is converted by [...] Read more.
The selective production of hydrocarbons for the chemical industry from biogenic feedstock is a significant challenge when ensuring hydrocarbon and fuel supply, despite the heterogeneity of this feed. In this study, guaiacol, as a surrogate for complex lignin-based biomass resources, is converted by an inert silica carrier material with different d-metal impregnation (Mo, W, Re, Fe, Co, Ni, Cu, Pd, Ag) to reveal the reasons for different product selectivity to hydrogenated and deoxygenated hydrocarbon products. Hydrogen at 15 bar (gauge) and guaiacol are converted on metal/silica catalysts between 250 °C and 400 °C, while the physicochemical catalyst properties are characterized before and after catalytic tests. Volcano plots for the conversion, hydrogenation and deoxygenation products versus the d-band energy, surface atom distance and fouling properties reveal three groups of metals: (i) those that are less active and show high coking (Ag, α-Fe); (ii) those that show high activity for hydrogenation (β-Co, Ni, Pd) and, therefore, preferably yielded cyclohexane, cyclohexanol and 2-methoxycyclohexanol; (iii) those that preferably promote deoxygenation (Mo, W, Re, Cu) and, therefore, promoted the formation of phenol, benzene, anisole and catechol. The results are summarized in a pseudo van Krevelen diagram and interpreted as a complex interdependency from Sabatier’s principle of geometric correspondence of hexagonal metal surface for hydrogenation, electronic correspondence for the activation of hydrogen and electronic correspondence by oxophilicity for deoxygenation from the d-band center model. Full article
(This article belongs to the Special Issue Catalysis on Zeolites and Zeolite-Like Materials II)
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14 pages, 2810 KiB  
Article
Influence of the Synthesis Protocol on the Catalytic Performance of PHI-Type Zeolites for the Dehydration of Lactic Acid
by Dorothea Häussermann, Richard Schömig, Barbara Gehring and Yvonne Traa
Catalysts 2023, 13(2), 261; https://doi.org/10.3390/catal13020261 - 24 Jan 2023
Cited by 1 | Viewed by 2133
Abstract
Acrylic acid is an important basic chemical and a key starting compound for a variety of consumer products. Today, acrylic acid is still produced from fossil-based propene. If acrylic acid were produced from bio-based lactic acid, this would be an important step towards [...] Read more.
Acrylic acid is an important basic chemical and a key starting compound for a variety of consumer products. Today, acrylic acid is still produced from fossil-based propene. If acrylic acid were produced from bio-based lactic acid, this would be an important step towards sustainability. The gas-phase dehydration reaction of lactic acid to acrylic acid was performed over eight-membered ring PHI-type zeolites in the Na+ and K+-form. A few variations in the synthesis procedure of PHI-type zeolite made a big difference in the performance during the catalytic reaction due to differences in the physical and chemical properties, especially the accessibility of the pores. The catalysts were characterized with ICP-OES, XRD, CO2 physisorption, SEM and 27Al MAS NMR. The calcination resulted in a partial collapse of the PHI structure. In the case of Na,K-PHI with a low surface area, the catalysis tends to take place on the outer surface, while in the case of Na,K-PHI with a high surface area the catalysis can also take place within the pore system. This has a considerable influence on the selectivity of the catalysts. Full article
(This article belongs to the Special Issue Catalysis on Zeolites and Zeolite-Like Materials II)
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13 pages, 2202 KiB  
Article
CO2 Hydrogenation to Renewable Methane on Ni/Ru Modified ZSM-5 Zeolites: The Role of the Preparation Procedure
by Margarita Popova, Manuela Oykova, Momtchil Dimitrov, Daniela Karashanova, Daniela Kovacheva, Genoveva Atanasova and Ágnes Szegedi
Catalysts 2022, 12(12), 1648; https://doi.org/10.3390/catal12121648 - 15 Dec 2022
Cited by 2 | Viewed by 2229
Abstract
Mono- and bimetallic Ni- and Ru-modified micro-mesoporous ZSM-5 catalysts were prepared by wet impregnation. The influence of the Ni content, the addition of Ru and the sequence of the modification by two metals on the physicochemical properties of the catalysts were studied. They [...] Read more.
Mono- and bimetallic Ni- and Ru-modified micro-mesoporous ZSM-5 catalysts were prepared by wet impregnation. The influence of the Ni content, the addition of Ru and the sequence of the modification by two metals on the physicochemical properties of the catalysts were studied. They were characterized by X-ray powder diffraction (XRD), N2 physisorption, temperature-programmed reduction (TPR-TGA), TEM and XPS spectroscopy. Formation of finely dispersed nickel and/or ruthenium oxide species was observed on the external surface and in the pores of zeolite support. It was found that the peculiarity of the used zeolite structure and the modification procedure determine the type of formed metal oxides, their dispersion and reducibility. XPS study revealed that the surface became rich in nickel and poorer in ruthenium for bimetallic catalysts. Ni had higher dispersion in the presence of ruthenium, and TPR investigations also confirmed its facilitated reducibility. The studied catalysts were tested in CO2 hydrogenation to methane. 10Ni5RuZSM-5 material showed the highest activity and high selectivity for methane formation, reaching the equilibrium conversion and 100% selectivity at 400 °C. Stability and reusability of the latter catalyst show that it is appropriate for practical application. Full article
(This article belongs to the Special Issue Catalysis on Zeolites and Zeolite-Like Materials II)
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21 pages, 4397 KiB  
Article
The Synthesis of Different Series of Cobalt BEA Zeolite Catalysts by Post-Synthesis Methods and Their Characterization
by Renata Sadek, Karolina Chalupka-Spiewak, Jean-Marc Krafft, Yannick Millot, Laetitia Valentin, Sandra Casale, Jacek Gurgul and Stanislaw Dzwigaj
Catalysts 2022, 12(12), 1644; https://doi.org/10.3390/catal12121644 - 15 Dec 2022
Cited by 3 | Viewed by 2241
Abstract
Three series of zeolite catalysts Co all-silica and Co Al-containing zeolites beta were prepared for use in the selective oxidative dehydrogenation of propane to propylene. Two series of zeolite catalysts Co all-silica were prepared by a two-step postsynthesis method at pH = 2.5 [...] Read more.
Three series of zeolite catalysts Co all-silica and Co Al-containing zeolites beta were prepared for use in the selective oxidative dehydrogenation of propane to propylene. Two series of zeolite catalysts Co all-silica were prepared by a two-step postsynthesis method at pH = 2.5 and pH = 3.0–9.0, respectively, which allows the incorporation of cobalt into SiBEA zeolite in the form of isolated framework pseudo-tetrahedral Co(II) species. The incorporation of Co ions into vacant T-atom sites and their reaction with silanol groups were demonstrated by NMR and FTIR methods. The generation of Lewis acid sites without the formation of Brønsted sites was proved by FTIR using pyridine and CO as probe molecules. The state of cobalt in three series of prepared and calcined zeolite catalysts was characterized by DR UV-vis. This technique allowed to show that for low Co content (<2 wt.%) cobalt is present in the form of framework pseudo-tetrahedral Co(II) species. For higher Co content (>2 wt.%), both framework pseudo-tetrahedral and extra-framework octahedral Co(II) species are present. The Co Al-containing zeolite beta series prepared on non-dealuminated support shows the presence of extra-framework octahedral Co(II) only. Full article
(This article belongs to the Special Issue Catalysis on Zeolites and Zeolite-Like Materials II)
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12 pages, 6444 KiB  
Article
The Activity of Ultrafine Cu Clusters Encapsulated in Nano-Zeolite for Selective Hydrogenation of CO2 to Methanol
by Ruiqin Ding, Guangying Fu, Songxia Wang, Yang Yang, Qiaolin Lang, Haonuan Zhao, Xiaobo Yang and Valentin Valtchev
Catalysts 2022, 12(11), 1296; https://doi.org/10.3390/catal12111296 - 23 Oct 2022
Cited by 5 | Viewed by 2598
Abstract
Narrowly dispersed ultrafine Cu clusters of sizes smaller than 2.0 nm have been encapsulated in nanosized silicalite-1 zeolite through direct crystallization in the presence of Cu(en)22+ complex ions as the metal precursor. The growing silicalite-1 crystals are rich in vacancy defects [...] Read more.
Narrowly dispersed ultrafine Cu clusters of sizes smaller than 2.0 nm have been encapsulated in nanosized silicalite-1 zeolite through direct crystallization in the presence of Cu(en)22+ complex ions as the metal precursor. The growing silicalite-1 crystals are rich in vacancy defects and connectivity defects on the grain boundaries, where the terminating silanols promote the decomposition of Cu(en)22+, thus the deposition of ultrafine Cu species. The obtained composite material as a model catalyst is active for CO2 activation and hydrogenation to methanol. The preliminary in situ FTIR study recognizes a series of surface-adsorbed carbonyl, formyl, carbonate, and formate species when the material is exposed to CO2 and H2. Among others, the adsorbed formate decays most rapidly upon cofeeding CO2 and H2, implying that the most probable pathway toward methanol formation over this material is via the formate-mediated mechanism. Full article
(This article belongs to the Special Issue Catalysis on Zeolites and Zeolite-Like Materials II)
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