Artículos de revistas: "Heterogeneous catalysis"

1

Muñoz-Batista, Mario J. y Rafael Luque. "Heterogeneous Photocatalysis". ChemEngineering 5, n.º 2 (25 de mayo de 2021): 26. http://dx.doi.org/10.3390/chemengineering5020026.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

2

Wan, Qiang, Sen Lin y Hua Guo. "Frustrated Lewis Pairs in Heterogeneous Catalysis: Theoretical Insights". Molecules 27, n.º 12 (10 de junio de 2022): 3734. http://dx.doi.org/10.3390/molecules27123734.

Texto completo

Resumen

Frustrated Lewis pair (FLP) catalysts have attracted much recent interest because of their exceptional ability to activate small molecules in homogeneous catalysis. In the past ten years, this unique catalysis concept has been extended to heterogeneous catalysis, with much success. Herein, we review the recent theoretical advances in understanding FLP-based heterogeneous catalysis in several applications, including metal oxides, functionalized surfaces, and two-dimensional materials. A better understanding of the details of the catalytic mechanism can help in the experimental design of novel heterogeneous FLP catalysts.

Los estilos APA, Harvard, Vancouver, ISO, etc.

3

Baráth, Eszter. "Selective Reduction of Carbonyl Compounds via (Asymmetric) Transfer Hydrogenation on Heterogeneous Catalysts". Synthesis 52, n.º 04 (2 de enero de 2020): 504–20. http://dx.doi.org/10.1055/s-0039-1691542.

Texto completo

Resumen

Based on the ever-increasing demand for optically pure compounds, the development of efficient methods to produce such products is very important. Homogeneous asymmetric catalysis occupies a prominent position in the ranking of chemical transformations, with transition metals coordinated to chiral ligands being applied extensively for this purpose. However, heterogeneous catalysts have the ability to further extend the field of asymmetric transformations, because of their beneficial properties such as high stability, ease of separation and regeneration, and the possibility to apply them in continuous processes. The main challenge is to find potential synthetic routes that can provide a chemically and thermally stable heterogeneous catalyst having the necessary chiral information, whilst keeping the catalytic activity and enantioselectivity equally high (or even higher) than the corresponding homogeneous counterpart. Within this short review, the most relevant immobilization modes and preparative strategies depending on the support material used are summarized. From the reaction scope viewpoint, metal catalysts supported on the various solid materials studied in (asymmetric) transfer hydrogenation of carbonyl compounds are selected and represent the main focus of the second part of this overview.1 Introduction2 Synthesis of Chiral Heterogeneous Catalysts2.1 Immobilization of Homogeneous Asymmetric Catalysts2.1.1 Immobilization on Inorganic Supports2.1.2 Immobilization on Organic Polymers as Supports2.1.3 Immobilization on Dendrimer-Type Materials as Supports2.1.4 Self-Supported Chiral Catalysts: Coordination Polymers2.1.5 Immobilization Using Non-Conventional Media2.2 Chirally Modified Metal Surfaces for Heterogeneous Asymmetric Catalysis3 Examples of Transfer Hydrogenation on Heterogeneous Catalysts3.1 Silicon-Immobilized Catalysts3.2 Carbon-Material-Immobilized Catalysts3.3 Polymer-Immobilized Catalysts3.4 Magnetic-Nanoparticle-Immobilized Catalysts4 Conclusions

Los estilos APA, Harvard, Vancouver, ISO, etc.

4

Motokura, Ken y Kyogo Maeda. "Recent Advances in Heterogeneous Ir Complex Catalysts for Aromatic C–H Borylation". Synthesis 53, n.º 18 (9 de abril de 2021): 3227–34. http://dx.doi.org/10.1055/a-1478-6118.

Texto completo

Resumen

AbstractAromatic C–H borylation catalyzed by an Ir complex is among the most powerful methods for activating inert bonds. The products, i.e., arylboronic acids and their esters, are usable chemicals for the Suzuki–Miyaura cross-coupling reaction, and significant effort has been directed toward the development of homogeneous catalysis chemistry. In this short review, we present a recent overview of current heterogeneous Ir-complex catalyst developments for aromatic C–H borylation. Not only have Ir complexes been immobilized on support surfaces with phosphine and bipyridine ligands, but Ir complexes incorporated within solid materials have also been developed as highly active and reusable heterogeneous Ir catalysts. Their catalytic activities and stabilities strongly depend on their surface structures, including linker length and ligand structure.1 Introduction and Homogeneous Ir Catalysis2 Heterogeneous Ir Complex Catalysts for C–H Borylation Reactions3 Other Heterogeneous Metal Complex Catalysts for C–H Borylation Reactions4 Summary and Outlook

Los estilos APA, Harvard, Vancouver, ISO, etc.

5

Kaplunenko, Volodymyr y Mykola Kosinov. "Electric field - induced catalysis. Laws of field catalysis". InterConf, n.º 26(129) (18 de octubre de 2022): 332–51. http://dx.doi.org/10.51582/interconf.19-20.10.2022.037.

Texto completo

Resumen

Abstract.The article explores a new type of catalysis - electric field catalysis. The laws of field catalysis are given. The characteristics of the electric field are determined, which set the values of the characteristics of the field catalysis. Field catalysis and field catalyst do not fit into the traditional definition of catalysis and catalyst, which may require a revision of the terminology of catalysis. The field is a more versatile catalyst compared to material catalysts, both in terms of its application to a wider range of chemical reactions, and in the ability to control the rate and selectivity. It is shown that a common donor-acceptor mechanism of catalysis is realized in heterogeneous and field catalysis. Generalized formulas are obtained, from which, as partial results, the laws of heterogeneous and field catalysis follow. New definitions of catalyst and field catalysis are given. The class of material catalysts has been expanded and supplemented with field catalysts.

Los estilos APA, Harvard, Vancouver, ISO, etc.

6

Lomic, Gizela, Erne Kis, Goran Boskovic y Radmila Marinkovic-Neducin. "Application of scanning electron microscopy in catalysis". Acta Periodica Technologica, n.º 35 (2004): 67–77. http://dx.doi.org/10.2298/apt0435067l.

Texto completo

Resumen

A short survey of various information obtained by scanning electron microscopy (SEM) in the investigation of heterogeneous catalysts and nano-structured materials have been presented. The capabilities of SEM analysis and its application in testing catalysts in different fields of heterogeneous catalysis are illustrated. The results encompass the proper way of catalyst preparation, the mechanism of catalyst active sites formation catalysts changes and catalyst degradation during their application in different chemical processes. Presented SEM pictures have been taken on a SEM JOEL ISM 35 over 25 years of studies in the field of heterogeneous catalysis.

Los estilos APA, Harvard, Vancouver, ISO, etc.

7

Shetty, Apoorva, Vandana Molahalli, Aman Sharma y Gurumurthy Hegde. "Biomass-Derived Carbon Materials in Heterogeneous Catalysis: A Step towards Sustainable Future". Catalysts 13, n.º 1 (23 de diciembre de 2022): 20. http://dx.doi.org/10.3390/catal13010020.

Texto completo

Resumen

Biomass-derived carbons are emerging materials with a wide range of catalytic properties, such as large surface area and porosity, which make them ideal candidates to be used as heterogeneous catalysts and catalytic supports. Their unique physical and chemical properties, such as their tunable surface, chemical inertness, and hydrophobicity, along with being environmentally friendly and cost effective, give them an edge over other catalysts. The biomass-derived carbon materials are compatible with a wide range of reactions including organic transformations, electrocatalytic reactions, and photocatalytic reactions. This review discusses the uses of materials produced from biomass in the realm of heterogeneous catalysis, highlighting the different types of carbon materials derived from biomass that are potential catalysts, and the importance and unique properties of heterogeneous catalysts with different preparation methods are summarized. Furthermore, this review article presents the relevant work carried out in recent years where unique biomass-derived materials are used as heterogeneous catalysts and their contribution to the field of catalysis. The challenges and potential prospects of heterogeneous catalysis are also discussed.

Los estilos APA, Harvard, Vancouver, ISO, etc.

8

Yam, Kah Meng, Na Guo, Zhuoling Jiang, Shulong Li y Chun Zhang. "Graphene-Based Heterogeneous Catalysis: Role of Graphene". Catalysts 10, n.º 1 (1 de enero de 2020): 53. http://dx.doi.org/10.3390/catal10010053.

Texto completo

Resumen

Graphene, the reincarnation of a surface, offers new opportunities in catalytic applications, not only because of its peculiar electronic structure, but also because of the ease of modulating it. A vast number of proposals have been made to support this point, but there has been a lack of a systematic understanding of the different roles of graphene, as many other reviews published have focused on the synthesis and characterization of the various graphene-based catalysts. In this review, we surveyed the vast literature related to various theoretical proposals and experimental realizations of graphene-based catalysts to first classify and then elucidate the different roles played by graphene in solid-state heterogeneous catalysis. Owing to its one-atom thickness and zero bandgap with low density of states around Fermi level, graphene has great potential in catalysis applications. In general, graphene can function as a support for catalysts, a cover to protect catalysts, or the catalytic center itself. Understanding these functions is important in the design of catalysts in terms of how to optimize the electronic structure of the active sites for particular applications, a few case studies of which will be presented for each role.

Los estilos APA, Harvard, Vancouver, ISO, etc.

9

Li, Shangkun, Rizwan Ahmed, Yanhui Yi y Annemie Bogaerts. "Methane to Methanol through Heterogeneous Catalysis and Plasma Catalysis". Catalysts 11, n.º 5 (1 de mayo de 2021): 590. http://dx.doi.org/10.3390/catal11050590.

Texto completo

Resumen

Direct oxidation of methane to methanol (DOMTM) is attractive for the increasing industrial demand of feedstock. In this review, the latest advances in heterogeneous catalysis and plasma catalysis for DOMTM are summarized, with the aim to pinpoint the differences between both, and to provide some insights into their reaction mechanisms, as well as the implications for future development of highly selective catalysts for DOMTM.

Los estilos APA, Harvard, Vancouver, ISO, etc.

10

Scholten, J. J. F. "Heterogeneous catalysis". Applied Catalysis 16, n.º 1 (abril de 1985): 130–32. http://dx.doi.org/10.1016/s0166-9834(00)84084-1.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

11

Mizuno, Noritaka y Makoto Misono. "Heterogeneous Catalysis". Chemical Reviews 98, n.º 1 (febrero de 1998): 199–218. http://dx.doi.org/10.1021/cr960401q.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

12

FULLENWIDER, M. y V. DENOFAJR. "Heterogeneous catalysis". International Journal of Hydrogen Energy 15, n.º 12 (1990): 913. http://dx.doi.org/10.1016/0360-3199(90)90081-9.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

13

Schlögl, Robert. "Heterogeneous Catalysis". Angewandte Chemie International Edition 54, n.º 11 (18 de febrero de 2015): 3465–520. http://dx.doi.org/10.1002/anie.201410738.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

14

Ranocchiari, Marco, Christian Lothschütz, Daniel Grolimund y Jeroen Anton van Bokhoven. "Single-atom active sites on metal-organic frameworks". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 468, n.º 2143 (14 de marzo de 2012): 1985–99. http://dx.doi.org/10.1098/rspa.2012.0078.

Texto completo

Resumen

Single-site heterogeneous catalysis has been recently accepted as a novel branch of heterogeneous catalysis. Catalysts with single-atom active sites (SAHCs) allow the design and fine-tuning of the active moiety, and can potentially combine the advantages of heterogeneous and homogeneous catalysis. This study illustrates how porous metal-organic frameworks (MOFs) can be synthesized with homogeneous distribution of SAHCs. The catalytic potential of MIXMOFs is shown. A short overview of catalysis with mesoporous silica materials is described to demonstrate their importance in SAHC.

Los estilos APA, Harvard, Vancouver, ISO, etc.

15

Hamzaoui, Bilel, Anissa Bendjeriou-Sedjerari, Eva Pump, Edy Abou-Hamad, Rachid Sougrat, Andrei Gurinov, Kuo-Wei Huang et al. "Atomic-level organization of vicinal acid–base pairs through the chemisorption of aniline and derivatives onto mesoporous SBA15". Chemical Science 7, n.º 9 (2016): 6099–105. http://dx.doi.org/10.1039/c6sc01229a.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

16

Liu, Jingyue. "Advanced Electron Microscopy Characterization of Nanostructured Heterogeneous Catalysts". Microscopy and Microanalysis 10, n.º 1 (22 de enero de 2004): 55–76. http://dx.doi.org/10.1017/s1431927604040310.

Texto completo

Resumen

Heterogeneous catalysis is one of the oldest nanosciences. Although model catalysts can be designed, synthesized, and, to a certain degree, characterized, industrial heterogeneous catalysts are often chemically and physically complex systems that have been developed through many years of catalytic art, technology, and science. The preparation of commercial catalysts is generally not well controlled and is often based on accumulated experiences. Catalyst characterization is thus critical to developing new catalysts with better activity, selectivity, and/or stability. Advanced electron microscopy, among many characterization techniques, can provide useful information for the fundamental understanding of heterogeneous catalysis and for guiding the development of industrial catalysts. In this article, we discuss the recent developments in applying advanced electron microscopy techniques to characterizing model and industrial heterogeneous catalysts. The importance of understanding the catalyst nanostructure and the challenges and opportunities of advanced electron microscopy in developing nanostructured catalysts are also discussed.

Los estilos APA, Harvard, Vancouver, ISO, etc.

17

Qin, Fengjuan y Wenxing Chen. "Copper-based single-atom alloys for heterogeneous catalysis". Chemical Communications 57, n.º 22 (2021): 2710–23. http://dx.doi.org/10.1039/d1cc00062d.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

18

Abu-Reziq, Raed y Howard Alper. "Magnetically Separable Base Catalysts: Heterogeneous Catalysis vs. Quasi-Homogeneous Catalysis". Applied Sciences 2, n.º 2 (26 de marzo de 2012): 260–76. http://dx.doi.org/10.3390/app2020260.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

19

Lian, Lifei, Huaiying Zhang, Sai An, Wei Chen y Yu-Fei Song. "Polyoxometalates-based heterogeneous catalysts in acid catalysis". Science China Chemistry 64, n.º 7 (20 de mayo de 2021): 1117–30. http://dx.doi.org/10.1007/s11426-020-9957-0.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

20

Ouyang, Like, Guo-Jin Da, Jun Ni, Jing Xu y Yi-Fan Han. "Heterogeneous Catalysis by Gold-based Bimetallic Catalysts". Recent Patents on Catalysis 2, n.º 1 (1 de abril de 2013): 2–46. http://dx.doi.org/10.2174/2211548x11302010002.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

21

Arai, Masahiko y Fengyu Zhao. "Metal Catalysts Recycling and Heterogeneous/Homogeneous Catalysis". Catalysts 5, n.º 2 (27 de mayo de 2015): 868–70. http://dx.doi.org/10.3390/catal5020868.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

22

ONO, Yoshio, Toshihide BABA, Kunihiko KANAE y Seong Gyu SEO. "Hydrogen-induced acid catalysis over heterogeneous catalysts." NIPPON KAGAKU KAISHI, n.º 7 (1988): 985–94. http://dx.doi.org/10.1246/nikkashi.1988.985.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

23

Ye, Rong, Tyler J. Hurlburt, Kairat Sabyrov, Selim Alayoglu y Gabor A. Somorjai. "Molecular catalysis science: Perspective on unifying the fields of catalysis". Proceedings of the National Academy of Sciences 113, n.º 19 (25 de abril de 2016): 5159–66. http://dx.doi.org/10.1073/pnas.1601766113.

Texto completo

Resumen

Colloidal chemistry is used to control the size, shape, morphology, and composition of metal nanoparticles. Model catalysts as such are applied to catalytic transformations in the three types of catalysts: heterogeneous, homogeneous, and enzymatic. Real-time dynamics of oxidation state, coordination, and bonding of nanoparticle catalysts are put under the microscope using surface techniques such as sum-frequency generation vibrational spectroscopy and ambient pressure X-ray photoelectron spectroscopy under catalytically relevant conditions. It was demonstrated that catalytic behavior and trends are strongly tied to oxidation state, the coordination number and crystallographic orientation of metal sites, and bonding and orientation of surface adsorbates. It was also found that catalytic performance can be tuned by carefully designing and fabricating catalysts from the bottom up. Homogeneous and heterogeneous catalysts, and likely enzymes, behave similarly at the molecular level. Unifying the fields of catalysis is the key to achieving the goal of 100% selectivity in catalysis.

Los estilos APA, Harvard, Vancouver, ISO, etc.

24

Cui, Xinjiang, Wu Li, Pavel Ryabchuk, Kathrin Junge y Matthias Beller. "Bridging homogeneous and heterogeneous catalysis by heterogeneous single-metal-site catalysts". Nature Catalysis 1, n.º 6 (junio de 2018): 385–97. http://dx.doi.org/10.1038/s41929-018-0090-9.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

25

Strekalova, Anna A., Anastasiya A. Shesterkina y Leonid M. Kustov. "Recent progress in hydrogenation of esters on heterogeneous bimetallic catalysts". Catalysis Science & Technology 11, n.º 22 (2021): 7229–38. http://dx.doi.org/10.1039/d1cy01603b.

Texto completo

Resumen

The development and research of highly effective heterogeneous catalysts for the hydrogenation of esters, providing high activity and selectivity of the formation of the corresponding alcohols, is an urgent task of modern heterogeneous catalysis.

Los estilos APA, Harvard, Vancouver, ISO, etc.

26

Vassalini, Irene y Ivano Alessandri. "Switchable Stimuli-Responsive Heterogeneous Catalysis". Catalysts 8, n.º 12 (22 de noviembre de 2018): 569. http://dx.doi.org/10.3390/catal8120569.

Texto completo

Resumen

Heterogeneous catalytic systems based on the use of stimuli-responsive materials can be switched from an “on” active state to an “off” inactive state, which contributes to endowing the catalysts with unique functional properties, such as adaptability, recyclability and precise spatial and temporal control on different types of chemical reactions. All these properties constitute a step toward the development of nature-inspired catalytic systems. Even if this is a niche area in the field of catalysis, it is possible to find in literature intriguing examples of dynamic catalysts, whose systematic analysis and review are still lacking. The aim of this work is to examine the recent developments of stimuli-responsive heterogeneous catalytic systems from the viewpoint of different approaches that have been proposed to obtain a dynamic control of catalytic efficiency. Because of the variety of reactions and conditions, it is difficult to make a quantitative comparison between the efficiencies of the considered systems, but the analysis of the different strategies can inspire the preparation of new smart catalytic systems.

Los estilos APA, Harvard, Vancouver, ISO, etc.

27

Zhou, Wei, Wei‐Qiao Deng y Xing Lu. "Metallosalen covalent organic frameworks for heterogeneous catalysis". Interdisciplinary Materials 3, n.º 1 (enero de 2024): 87–112. http://dx.doi.org/10.1002/idm2.12140.

Texto completo

Resumen

AbstractMetallosalen covalent organic frameworks (M(salen)‐COFs) have garnered significant attention as promising candidates for advanced heterogeneous catalysis, including organocatalysis, electrocatalysis, and photocatalysis, due to their unique structural advantages (combining molecules catalysts and crystalline porous materials) and tunable topological network. It is essential to provide a comprehensive overview of emerging designs of M(salen)‐COFs and corresponding advances in this field. Herein, this review first summarizes the reported metallolinkers and the synthesis methods of M(salen)‐COFs. In addition, the review enumerates the excellent M(salen)‐COF based heterogeneous catalysts and discusses the fundamental mechanisms behind the outstanding heterogeneous catalytic performance of M(salen)‐COFs. These mechanisms include the pore enrichment effect (enhancing local concentration within porous materials to promote catalytic reactions), the three‐in‐one strategy (integrating enrichment, reduction, and oxidation sites in one system), and the incorporation of a built‐in electric field (implanting a built‐in electric field in heterometallic phthalocyanine covalent organic frameworks). Furthermore, this review discusses the challenges and prospects related to M(salen)‐COFs in heterogeneous catalysis.

Los estilos APA, Harvard, Vancouver, ISO, etc.

28

BOUSBA, DALILA, CHAFIA SOBHI, AMNA ZOUAOUI y SOUAD BOUASLA. "Synthesis of activated carbon sand their application in the synthesis of monometallic and bimetallic supported catalysts". Algerian Journal of Signals and Systems 5, n.º 4 (15 de diciembre de 2020): 190–96. http://dx.doi.org/10.51485/ajss.v5i4.116.

Texto completo

Resumen

Biomass-derived porous carbons are attractive materials for the synthesis of carbon-supported catalysts, carbonaceous catalysts are environmentally benign and could provide an important competitive advantage as compared to existing heterogeneous catalysts, however the surface properties of carbon materials and excellent physical and chemical properties are compatible with diverse catalysis reactions including organic transformations. Currently, activated carbons are one of well known carbonaceous materials for their catalytic properties and for use as support in heterogeneous catalysis. The supported catalysts have been successfully used in the chemical industries for a long time, in which carbon supported catalysts have allowed to a new chemical catalytic process, on the other hand Heterogeneous catalysis plays a key role in the manufacture of essential products in different fields. In this paper, we present a comparative study, between two main different methods for activated carbons (ACs) preparation namely, physical and chemical activations. Latter was prepared from agro-industrial biomass and used as a support to prepare monometallic (dry impregnation and excess impregnation) and bimetallic catalyst (successive impregnation and co impregnation).

Los estilos APA, Harvard, Vancouver, ISO, etc.

29

Khan, Haris Mahmood, Tanveer Iqbal, Saima Yasin, Muhammad Irfan, Muhammad Mujtaba Abbas, Ibham Veza, Manzoore Elahi M. Soudagar, Anas Abdelrahman y Md Abul Kalam. "Heterogeneous Catalyzed Biodiesel Production Using Cosolvent: A Mini Review". Sustainability 14, n.º 9 (22 de abril de 2022): 5062. http://dx.doi.org/10.3390/su14095062.

Texto completo

Resumen

Biodiesel is gaining recognition as a good replacement for typical diesel owing to its renewability, sustainability, and eco-friendly nature. Transesterification is the leading route for biodiesel generation, which occurs during homogeneous/heterogeneous/enzymatic catalysis. Besides this, the usage of heterogeneous catalysts is considered more advantageous over homogeneous catalysts due to the easy catalyst recovery. Consequently, numerous heterogeneous catalysts have been synthesized from multiple sources with the intention of making the manufacturing process more efficient and cost-effective. Alongside this, numerous researchers have attempted to improve the biodiesel yield using heterogeneous catalysts by introducing cosolvents, such that phase limitation between oil and alcohol can be minimized. This short review is aimed at examining the investigations performed to date on heterogeneously catalyzed biodiesel generation in the presence of different cosolvents. It encompasses the techniques for heterogeneous catalyst synthesis, reported in the literature available for heterogeneous catalyzed biodiesel generation using cosolvents and their effects. It also suggests that the application of cosolvent in heterogeneously catalyzed three-phase systems substantially reduces the mass transfer limitation between alcohol and oil phases, which leads to enhancements in biodiesel yield along with reductions in values of optimized parameters, with catalyst weight ranges from 1 to 15 wt. %, and alcohol/oil ratio ranges from 5.5 to 20. The reaction time for getting the maximum conversion ranges from 10 to 600 min in the presence of different cosolvents. Alongside this, most of the time, the biodiesel yield remained above 90% in the presence of cosolvents.

Los estilos APA, Harvard, Vancouver, ISO, etc.

30

Miceli, Mariachiara, Patrizia Frontera, Anastasia Macario y Angela Malara. "Recovery/Reuse of Heterogeneous Supported Spent Catalysts". Catalysts 11, n.º 5 (1 de mayo de 2021): 591. http://dx.doi.org/10.3390/catal11050591.

Texto completo

Resumen

The rapid separation and efficient recycling of catalysts after a catalytic reaction are considered important requirements along with the high catalytic performances. In this view, although heterogeneous catalysis is generally less efficient if compared to the homogeneous type, it is generally preferred since it benefits from the easy recovery of the catalyst. Recycling of heterogeneous catalysts using traditional methods of separation such as extraction, filtration, vacuum distillation, or centrifugation is tedious and time-consuming. They are uneconomic processes and, hence, they cannot be carried out in the industrial scale. For these limitations, today, the research is devoted to the development of new methods that allow a good separation and recycling of catalysts. The separation process should follow a procedure economically and technically feasible with a minimal loss of the solid catalyst. The aim of this work is to provide an overview about the current trends in the methods of separation/recycling used in the heterogeneous catalysis.

Los estilos APA, Harvard, Vancouver, ISO, etc.

31

Karakhanov, Eduard, Anton Maximov y Anna Zolotukhina. "Heterogeneous Dendrimer-Based Catalysts". Polymers 14, n.º 5 (28 de febrero de 2022): 981. http://dx.doi.org/10.3390/polym14050981.

Texto completo

Resumen

The present review compiles the advances in the dendritic catalysis within the last two decades, in particular concerning heterogeneous dendrimer-based catalysts and their and application in various processes, such as hydrogenation, oxidation, cross-coupling reactions, etc. There are considered three main approaches to the synthesis of immobilized heterogeneous dendrimer-based catalysts: (1) impregnation/adsorption on silica or carbon carriers; (2) dendrimer covalent grafting to various supports (silica, polystyrene, carbon nanotubes, porous aromatic frameworks, etc.), which may be performed in a divergent (as a gradual dendron growth on the support) or convergent way (as a grafting of whole dendrimer to the support); and (3) dendrimer cross-linking, using transition metal ions (resulting in coordination polymer networks) or bifunctional organic linkers, whose size, polarity, and rigidity define the properties of the resulted material. Additionally, magnetically separable dendritic catalysts, which can be synthesized using the three above-mentioned approaches, are also considered. Dendritic catalysts, synthesized in such ways, can be stored as powders and be easily separated from the reaction medium by filtration/centrifugation as traditional heterogeneous catalysts, maintaining efficiency as for homogeneous dendritic catalysts.

Los estilos APA, Harvard, Vancouver, ISO, etc.

32

Hutchings, Graham J. "Heterogeneous Gold Catalysis". ACS Central Science 4, n.º 9 (27 de julio de 2018): 1095–101. http://dx.doi.org/10.1021/acscentsci.8b00306.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

33

George, Steven M. "Introduction: Heterogeneous Catalysis". Chemical Reviews 95, n.º 3 (mayo de 1995): 475–76. http://dx.doi.org/10.1021/cr00035a001.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

34

Hattori, Hideshi. "Heterogeneous Basic Catalysis". Chemical Reviews 95, n.º 3 (mayo de 1995): 537–58. http://dx.doi.org/10.1021/cr00035a005.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

35

WILSON, ELIZABETH. "HETEROGENEOUS TANDEM CATALYSIS". Chemical & Engineering News Archive 89, n.º 16 (18 de abril de 2011): 9. http://dx.doi.org/10.1021/cen-v089n016.p009.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

36

Lemaire, Marc. "Heterogeneous asymmetric catalysis". Pure and Applied Chemistry 76, n.º 3 (1 de enero de 2004): 679–88. http://dx.doi.org/10.1351/pac200476030679.

Texto completo

Resumen

Examples of enantioselective catalysts, including homogeneous supported catalysts and biphasic liquid/liquid, are described and compared. In the case of asymmetric hydride transfer, polythiourea was proven to be more efficient for ruthenium-catalyzed reduction of arylketones, although the iridium complexes gave rise to higher ee when using amino sulfonamide bound to a polystyrene matrix. In the case of asymmetric reduction, the modification of the binap allows the formation of a polymer that could be used as a catalyst precursor and exhibits enantioselectivities as high as observed in solution, but easier to separate and recycle. Bisoxazoline bound to silica particules could also be used in copper-catalyzed asymmetric Diels-Alder reaction and cyclopropanation with selectivities similar to that obtained in solution.

Los estilos APA, Harvard, Vancouver, ISO, etc.

37

Heitbaum, Maja, Frank Glorius y Iris Escher. "Asymmetric Heterogeneous Catalysis". Angewandte Chemie International Edition 45, n.º 29 (17 de julio de 2006): 4732–62. http://dx.doi.org/10.1002/anie.200504212.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

38

Rase, Howard F. y M. Hayes. "Commercial Heterogeneous Catalysis". Platinum Metals Review 45, n.º 2 (1 de abril de 2001): 83. http://dx.doi.org/10.1595/003214001x4528383.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

39

Collier, P. J. "Understanding Heterogeneous Catalysis". Platinum Metals Review 47, n.º 3 (1 de julio de 2003): 110. http://dx.doi.org/10.1595/003214003x473110110.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

40

Chen, Wei, Binbin Wu, Yanyong Wang, Wang Zhou, Yingying Li, Tianyang Liu, Chao Xie et al. "Deciphering the alternating synergy between interlayer Pt single-atom and NiFe layered double hydroxide for overall water splitting". Energy & Environmental Science 14, n.º 12 (2021): 6428–40. http://dx.doi.org/10.1039/d1ee01395e.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

41

Mazaheri, Hoora, Hwai Chyuan Ong, Zeynab Amini, Haji Hassan Masjuki, M. Mofijur, Chia Hung Su, Irfan Anjum Badruddin y T. M. Yunus Khan. "An Overview of Biodiesel Production via Calcium Oxide Based Catalysts: Current State and Perspective". Energies 14, n.º 13 (1 de julio de 2021): 3950. http://dx.doi.org/10.3390/en14133950.

Texto completo

Resumen

Biodiesel is a clean, renewable, liquid fuel that can be used in existing diesel engines without modification as pure or blend. Transesterification (the primary process for biodiesel generation) via heterogeneous catalysis using low-cost waste feedstocks for catalyst synthesis improves the economics of biodiesel production. Heterogeneous catalysts are preferred for the industrial generation of biodiesel due to their robustness and low costs due to the easy separation and relatively higher reusability. Calcium oxides found in abundance in nature, e.g., in seashells and eggshells, are promising candidates for the synthesis of heterogeneous catalysts. However, process improvements are required to design productive calcium oxide-based catalysts at an industrial scale. The current work presents an overview of the biodiesel production advancements using calcium oxide-based catalysts (e.g., pure, supported, and mixed with metal oxides). The review discusses different factors involved in the synthesis of calcium oxide-based catalysts, and the effect of reaction parameters on the biodiesel yield of calcium oxide-based catalysis are studied. Further, the common reactor designs used for the heterogeneous catalysis using calcium oxide-based catalysts are explained. Moreover, the catalytic activity mechanism, challenges and prospects of the application of calcium oxide-based catalysts in biodiesel generation are discussed. The study of calcium oxide-based catalyst should continue to be evaluated for the potential of their application in the commercial sector as they remain the pivotal goal of these studies.

Los estilos APA, Harvard, Vancouver, ISO, etc.

42

Jianchen, Wang, Kang Yong y Fangkuan Sun. "Mass production of thermally stable Pt single-atom catalysts for the catalytic oxidation of sulfur dioxide". Catalysis Science & Technology 12, n.º 1 (2022): 124–34. http://dx.doi.org/10.1039/d1cy01578h.

Texto completo

Resumen

Owing to the 100% atom utilization and the potential in bridging the gap between homogeneous catalysis and heterogeneous catalysis, single-atom catalysts (SACs) have doubtlessly obtained broad attention from both academia and industry.

Los estilos APA, Harvard, Vancouver, ISO, etc.

43

Chaparro-Garnica, Cristian Yesid, Esther Bailón-García, Arantxa Davó-Quiñonero, Patrick Da Costa, Dolores Lozano-Castelló y Agustín Bueno-López. "High Performance Tunable Catalysts Prepared by Using 3D Printing". Materials 14, n.º 17 (2 de septiembre de 2021): 5017. http://dx.doi.org/10.3390/ma14175017.

Texto completo

Resumen

Honeycomb monoliths are the preferred supports in many industrial heterogeneous catalysis reactions, but current extrusion synthesis only allows obtaining parallel channels. Here, we demonstrate that 3D printing opens new design possibilities that outperform conventional catalysts. High performance carbon integral monoliths have been prepared with a complex network of interconnected channels and have been tested for carbon dioxide hydrogenation to methane after loading a Ni/CeO2 active phase. CO2 methanation rate is enhanced by 25% at 300 °C because the novel design forces turbulent flow into the channels network. The methodology and monoliths developed can be applied to other heterogeneous catalysis reactions, and open new synthesis options based on 3D printing to manufacture tailored heterogeneous catalysts.

Los estilos APA, Harvard, Vancouver, ISO, etc.

44

Trunschke, Annette, Giulia Bellini, Maxime Boniface, Spencer J. Carey, Jinhu Dong, Ezgi Erdem, Lucas Foppa et al. "Towards Experimental Handbooks in Catalysis". Topics in Catalysis 63, n.º 19-20 (6 de octubre de 2020): 1683–99. http://dx.doi.org/10.1007/s11244-020-01380-2.

Texto completo

Resumen

AbstractThe “Seven Pillars” of oxidation catalysis proposed by Robert K. Grasselli represent an early example of phenomenological descriptors in the field of heterogeneous catalysis. Major advances in the theoretical description of catalytic reactions have been achieved in recent years and new catalysts are predicted today by using computational methods. To tackle the immense complexity of high-performance systems in reactions where selectivity is a major issue, analysis of scientific data by artificial intelligence and data science provides new opportunities for achieving improved understanding. Modern data analytics require data of highest quality and sufficient diversity. Existing data, however, frequently do not comply with these constraints. Therefore, new concepts of data generation and management are needed. Herein we present a basic approach in defining best practice procedures of measuring consistent data sets in heterogeneous catalysis using “handbooks”. Selective oxidation of short-chain alkanes over mixed metal oxide catalysts was selected as an example.

Los estilos APA, Harvard, Vancouver, ISO, etc.

45

Kerketta, Ujjaval, Alexander B. Tesler y Patrik Schmuki. "Single-Atom Co-Catalysts Employed in Titanium Dioxide Photocatalysis". Catalysts 12, n.º 10 (12 de octubre de 2022): 1223. http://dx.doi.org/10.3390/catal12101223.

Texto completo

Resumen

With a distinct electronic structure and unsaturated coordination centers, supported single-atoms (SAs) have shown great potential in heterogeneous catalysis due to their superior activity, stability, and selectivity. Over the last few years, the fascination of SA-use spread also over photocatalysis, i.e., a particular case of heterogeneous catalysis in which chemical reactions are activated by charge transfer from an illuminated semiconductor. Titanium dioxide (TiO2) is one of the most studied photocatalytic materials. It is widely used as a light absorbing semiconductor decorated with metallic (nanoparticles and single-atom) co-catalysts. In the current review, we emphasize the role of SAs as a co-catalyst in photocatalysis, and clearly set it apart from the use of single atoms in classic heterogeneous catalysis. The review first briefly describes the principal features of SAs, and gives an overview of most important examples of single-atom co-catalysts. Then, we discuss photocatalysis and key examples of single-atom co-catalysts used on TiO2 photocatalysts and their applications. At last, we provide an outlook for further exploring TiO2-based single-atom photocatalytic systems.

Los estilos APA, Harvard, Vancouver, ISO, etc.

46

Guo, Hongchao y Kuiling Ding. "Self-supported Chiral Catalysts for Heterogeneous Asymmetric Catalysis". CHIMIA International Journal for Chemistry 65, n.º 12 (14 de diciembre de 2011): 932–38. http://dx.doi.org/10.2533/chimia.2011.932.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

47

Mayer-Gall, Thomas, Ji-Woong Lee, Klaus Opwis, Benjamin List y Jochen S. Gutmann. "Textile Catalysts-An unconventional approach towards heterogeneous catalysis". ChemCatChem 8, n.º 8 (24 de marzo de 2016): 1428–36. http://dx.doi.org/10.1002/cctc.201501252.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

48

Bogdan, Elżbieta y Piotr Michorczyk. "3D Printing in Heterogeneous Catalysis—The State of the Art". Materials 13, n.º 20 (13 de octubre de 2020): 4534. http://dx.doi.org/10.3390/ma13204534.

Texto completo

Resumen

This paper describes the process of additive manufacturing and a selection of three-dimensional (3D) printing methods which have applications in chemical synthesis, specifically for the production of monolithic catalysts. A review was conducted on reference literature for 3D printing applications in the field of catalysis. It was proven that 3D printing is a promising production method for catalysts.

Los estilos APA, Harvard, Vancouver, ISO, etc.

49

Zhou, Chuan, Binghu Zhang, P. Hu y Haifeng Wang. "An effective structural descriptor to quantify the reactivity of lattice oxygen in CeO2 subnano-clusters". Physical Chemistry Chemical Physics 22, n.º 3 (2020): 1721–26. http://dx.doi.org/10.1039/c9cp05805b.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

50

Maksimchuk, Nataliya V., Olga V. Zalomaeva, Igor Y. Skobelev, Konstantin A. Kovalenko, Vladimir P. Fedin y Oxana A. Kholdeeva. "Metal–organic frameworks of the MIL-101 family as heterogeneous single-site catalysts". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 468, n.º 2143 (14 de marzo de 2012): 2017–34. http://dx.doi.org/10.1098/rspa.2012.0072.

Texto completo

Resumen

In this short review paper, we survey our recent findings in the catalytic applications of mesoporous metal–organic frameworks of the MIL-101 family (Fe- and Cr-MIL-101) and demonstrate their potential in two types of liquid-phase processes: (i) selective oxidation of hydrocarbons with green oxidants—O 2 and tert -butyl hydroperoxide—and (ii) coupling reaction of organic oxides with CO 2 . A comparison with conventional single-site catalysts is made with special attention to issues of the catalyst's resistance to metal leaching and the nature of catalysis.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Artículos de revistas sobre el tema "Heterogeneous catalysis"

Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros