Bibliografie tematiche / Homogenous catalysts

Letteratura scientifica selezionata sul tema "Homogenous catalysts"

Autore: Grafiati

Pubblicato: 22 giugno 2024

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Articoli di riviste sul tema "Homogenous catalysts":

Testa, Maria Luisa, e Valeria La Parola. "Sulfonic Acid-Functionalized Inorganic Materials as Efficient Catalysts in Various Applications: A Minireview". Catalysts 11, n. 10 (23 settembre 2021): 1143. http://dx.doi.org/10.3390/catal11101143.

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Acid catalysis is widely used in the chemical industry, and nowadays many efforts are being focused on replacing the more common homogeneous catalysts with heterogeneous ones in order to make greener the industrial processes. In this perspective, sulfonic solid acid materials represent a valid alternative to the homogenous mineral acid in several acid catalyzed reactions. In this minireview, an overview of the recent advances on the preparation, stability and application of these materials is reported. Special attention is addressed to the sustainability of the considered processes, starting from the catalyst’s preparation, the use of green solvents and reducing the possible reaction steps. Ways to tackle the main drawback represented by easy leaching of acid groups are described. For an easy catalyst recovery, the use of a magnetic core in a catalyst particle, with the related synthetic approaches, is also illustrated. Finally, a section is dedicated to the principal characterization techniques to identify the structural properties of the catalysts.

Guerrero Fajardo, Carlos Alberto, Yvonne N’Guyen, Claire Courson e Anne Cécile Roger. "Fe/SiO2 catalysts for the selective oxidation of methane to formaldehyde". Ingeniería e Investigación 26, n. 2 (1 maggio 2006): 37–44. http://dx.doi.org/10.15446/ing.investig.v26n2.14735.

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Selective oxidation of methane to formaldehyde was analysed with iron catalysts supported on silica prepared by the sol-gel method, leading to obtaining a large support surface area facilitating high dispersion of iron on silica’s amorphous surface. Seven catalysts were prepared; one of them corresponded to the silica support and another five having an iron load 0.1-0.5% in weight. Catalyst 7 (0.5% Fe in weight) was prepared with neutral pH control and had the most homogeneous characteristics since it did not present isolated iron species, corroborated by SEM and TEM analysis. The highest BET areas were 1,757 and 993 m2.g-1 for 0.5% Fe catalysts, having an average 36% microporosity and 43% mesoporosity. X-ray diffraction confirmed the catalyst’s amorphous structure. Catalytic activity was carried out with catalyser 7 at atmospheric pressure in a quartz reactor using a CH4/O2/N2=7.5/1/4 reaction mixture at 400-750°C temperature range. Reaction products were analysed by gas chromatography with TCD. The heterogeneous catalysts displayed greater methane conversion (but with methanol selectivity) whereas homogenous catalyst 7 gave better results regarding formaldehyde. The highest conversion percentage (8.60% mol) for catalyser 7 was presented at 650°C. Formaldehyde selectivity was 50% mol in the 600-650°C range and maximum yield (0.31g HCHO/Kg catalyst) was found in this range; it was thus considered that 650°C for the reaction was thereby the best operating temperature.

García-Álvarez, Joaquín. "Special Issue: “Advances in Homogeneous Catalysis”". Molecules 25, n. 7 (25 marzo 2020): 1493. http://dx.doi.org/10.3390/molecules25071493.

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The use of enzymes, organo-catalysts or transition metal catalysts, as opposed to the employment of stoichiometric quantities of other traditional promoters of different organic synthetic processes (like, inorganic/organic bases, Brønsted acids, radicals, etc.) has allowed the discovery of a great number of new synthetic protocols within the toolbox of organic chemists. Moreover, the employment of the aforementioned catalysts in organic synthesis permits: (i) the diminution of the global energy demand and production cost; (ii) the enhancement of both the chemoselectivity and stereoselectivity of the global process; and (iii) the reduction of metal-, organo- or bio-catalyst consumption, thanks to the possible recycling of the catalysts; all these being synthetic concepts closely related with the principles of so-called Green Chemistry. Thus, this Special Issue on “Advances in Homogenous Catalysis” has been aimed to showcase a series of stimulating contributions from international experts within different sub-areas of catalysis in organic synthesis (ranging from metal-, organo-, or bio-catalyzed organic reactions).

Zhao, Da, Roland Petzold, Jiyao Yan, Dieter Muri e Tobias Ritter. "Tritiation of aryl thianthrenium salts with a molecular palladium catalyst". Nature 600, n. 7889 (15 dicembre 2021): 444–49. http://dx.doi.org/10.1038/s41586-021-04007-y.

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AbstractTritium labelling is a critical tool for investigating the pharmacokinetic and pharmacodynamic properties of drugs, autoradiography, receptor binding and receptor occupancy studies1. Tritium gas is the preferred source of tritium for the preparation of labelled molecules because it is available in high isotopic purity2. The introduction of tritium labels from tritium gas is commonly achieved by heterogeneous transition-metal-catalysed tritiation of aryl (pseudo)halides. However, heterogeneous catalysts such as palladium supported on carbon operate through a reaction mechanism that also results in the reduction of other functional groups that are prominently featured in pharmaceuticals3. Homogeneous palladium catalysts can react chemoselectively with aryl (pseudo)halides but have not been used for hydrogenolysis reactions because, after required oxidative addition, they cannot split dihydrogen4. Here we report a homogenous hydrogenolysis reaction with a well defined, molecular palladium catalyst. We show how the thianthrene leaving group—which can be introduced selectively into pharmaceuticals by late-stage C–H functionalization5—differs in its coordinating ability to relevant palladium(II) catalysts from conventional leaving groups to enable the previously unrealized catalysis with dihydrogen. This distinct reactivity combined with the chemoselectivity of a well defined molecular palladium catalyst enables the tritiation of small-molecule pharmaceuticals that contain functionality that may otherwise not be tolerated by heterogeneous catalysts. The tritiation reaction does not require an inert atmosphere or dry conditions and is therefore practical and robust to execute, and could have an immediate impact in the discovery and development of pharmaceuticals.

Russell, M. J. H. "Water Soluble Rhodium Catalysts". Platinum Metals Review 32, n. 4 (1 ottobre 1988): 179–86. http://dx.doi.org/10.1595/003214088x324179186.

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The rhodium catalysed hydroformylation reaction is one of the most widely used industrial applications of homogenous catalysis to employ platinum group metals. Potential limitations in the application of this technology to molecules which are heat sensitive or have high boiling points are the stability of the catalyst and the ability to separate the catalyst from the products. A means of circumventing these limitations is described. This involves locating the catalyst in an aqueous liquid phase, and it enables viable reaction rates to be achieved at moderate temperatures and pressures.

Lowe, Brandon, Jabbar Gardy e Ali Hassanpour. "The Role of Sulfated Materials for Biodiesel Production from Cheap Raw Materials". Catalysts 12, n. 2 (16 febbraio 2022): 223. http://dx.doi.org/10.3390/catal12020223.

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There is an urgent need to reduce global greenhouse gas emissions, yet to date the decarbonization of the transportation industry has been slow and of particular difficulty. While fossil fuel replacements such as biodiesel may aid the transition to a less polluting society, production at the industrial scales required is currently heavily dependent on chemical catalysis. Conventional two-step homogenous routes require the challenging separation of catalyst from the obtained product; however, heterogenous solid catalysts bring new considerations such as material stability, surface area, porosity, deactivation effects, and reduced reactivities under mild conditions. Nanomaterials present an attractive solution, offering the high reactivity of homogenous catalysts without complex recyclability issues. Slightly less reactive, acidic sulfated nanomaterials may also demonstrate greater stability to feedstock impurity, extending lifetime and improved versatility to a range of starting feeds. There remains, however, much work to be done in demonstrating the full-scale feasibility of such catalysts. This review explores recent developments over time in acidic sulfated nanocatalysis for biodiesel production, with particular focus on metal oxides, magnetic nanoparticles, silica-supported nanomaterials, and acidic carbon nanocatalysts. Included are various summaries of current progress in the literature, as well as recommendations for future research.

Latos, Piotr, Anna Wolny e Anna Chrobok. "Supported Ionic Liquid Phase Catalysts Dedicated for Continuous Flow Synthesis". Materials 16, n. 5 (5 marzo 2023): 2106. http://dx.doi.org/10.3390/ma16052106.

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Heterogeneous catalysis, although known for over a century, is constantly improved and plays a key role in solving the present problems in chemical technology. Thanks to the development of modern materials engineering, solid supports for catalytic phases having a highly developed surface are available. Recently, continuous-flow synthesis started to be a key technology in the synthesis of high added value chemicals. These processes are more efficient, sustainable, safer and cheaper to operate. The most promising is the use of heterogeneous catalyst with column-type fixed-bed reactors. The advantages of the use of heterogeneous catalyst in continuous flow reactors are the physical separation of product and catalyst, as well as the reduction in inactivation and loss of the catalyst. However, the state-of-the-art use of heterogeneous catalysts in flow systems compared to homogenous ones remains still open. The lifetime of heterogeneous catalysts remains a significant hurdle to realise sustainable flow synthesis. The goal of this review article was to present a state of knowledge concerning the application of Supported Ionic Liquid Phase (SILP) catalysts dedicated for continuous flow synthesis.

Nishchakova, Alina D., Lyubov G. Bulusheva e Dmitri A. Bulushev. "Supported Ni Single-Atom Catalysts: Synthesis, Structure, and Applications in Thermocatalytic Reactions". Catalysts 13, n. 5 (6 maggio 2023): 845. http://dx.doi.org/10.3390/catal13050845.

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Nickel is a well-known catalyst in hydrogenation and dehydrogenation reactions. It is currently used in industrial processes as a homogenous and heterogeneous catalyst. However, to reduce the cost and increase the efficiency of catalytic processes, the development of single-atom catalysts (SACs) seems promising. Some SACs have already shown increased activity and stability as compared to nanoparticle catalysts. From year to year, the number of reports devoted to nickel SACs is growing rapidly. Among them, there are very few articles devoted to thermal catalysis, but at the same time, this subject is important. Thus, this review discusses recent advances in the synthesis, structure, and application of nickel SACs, mainly in catalytic hydrogenation/dehydrogenation reactions and in the dry reforming of methane. The collected and analyzed data can be useful in the development of novel nickel SACs for various processes.

Ali, Syed Danish, Isma Noreen Javed, Usman Ali Rana, Muhammad Faizan Nazar, Waqas Ahmed, Asifa Junaid, Mahmood Pasha, Rumana Nazir e Rizwana Nazir. "Novel SrO-CaO Mixed Metal Oxides Catalyst for Ultrasonic-Assisted Transesterification of Jatropha Oil into Biodiesel". Australian Journal of Chemistry 70, n. 3 (2017): 258. http://dx.doi.org/10.1071/ch16236.

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The transesterification of edible and non-edible oils to produce biodiesel is traditionally carried out using homogeneous catalysts (such as NaOH, KOH, and H2SO4). However, these homogenous catalysts often suffer from multiple drawbacks including their corrosive nature and solubility in the reaction mixture, and high costs associated with their recovery. Recent studies have shown that heterogeneous catalysts based on mixed metal oxides have the potential to address the issues associated with conventional homogeneous catalysts, thereby emerging as an efficient class of catalyst materials for biodiesel production. In this study, we describe a heterogeneous strontium oxide/calcium oxide (SrO-CaO) mixed metal oxides catalyst, which displays remarkable efficiency towards the ultrasonic-assisted transesterification of Jatropha oil into biodiesel. The SrO-CaO heterogeneous catalyst was prepared by the wet impregnation method, and the structural morphology of the as-synthesized catalyst was revealed by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and nitrogen sorption technique coupled with the Brunauer–Emmett–Teller and Barrett–Joyner–Halenda methods. The X-ray diffraction analysis confirmed the cubic structure of the SrO-CaO catalyst. The catalytic activity of this newly developed catalyst showed a high percentage conversion of triglyceride into the corresponding fatty acid methyl esters (98.19 %) as confirmed by 1H NMR spectroscopy. The chemical composition of the prepared biodiesel by this ultrasonic-assisted transesterification process was determined by the gas chromatography–mass spectrometry. Five major fatty acid methyl esters were identified, of which 9-octadecenoic acid methyl ester was obtained with the highest percentage ~38.22 %. Hence, the study reveals that the SrO-CaO catalyst exhibits high efficiency towards converting Jatropha oil into biodiesel by ultrasonic-assisted transesterification.

Balcer, Sylwia. "Homogeneous catalytic systems for selective oxidation of methane: state of the art". Polish Journal of Chemical Technology 17, n. 3 (1 settembre 2015): 52–61. http://dx.doi.org/10.1515/pjct-2015-0050.

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AbstractHomogeneous catalysts for methane oxidation are of a particular interest from scientific and economic points of view. The results show a great potential for activation and functionalization of CH bonds of unreactive methane. There are still gaps in the knowledge of how to rationally design catalysts for this process. In this paper state-of-the-art. in methane oxidation homogenous catalysis is presented.

Più fonti

Tesi sul tema "Homogenous catalysts":

Ruiz, Botella Sheila. "The importance of ligand design for the development of supramolecular catalysts and ion receptors". Doctoral thesis, Universitat Jaume I, 2017. http://hdl.handle.net/10803/402550.

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La tesis está dividida en dos partes claramente diferenciadas. La primera parte trata sobre aspectos concernientes a la catálisis supramolecular. Los trabajos descritos están basados en el diseño de nuevos ligandos N-heterociclicos con diferentes topologías y funcionalidades, los cuales fueron coordinados a diferentes centros metálicos. Los complejos sintetizados fueron caracterizados y estudiados en catálisis, con el objetivo principal de estudiar los efectos producidos por los ligandos orgánicos debido a interacciones del tipo no covalentes. Estos complejos o catalizadores también fueron soportados y estudiados en catálisis heterogénea. La segunda parte de la tesis se centra en estudios de química supramolecular host-guest. Los trabajos descritos en esta parte describen la preparación de nuevos receptores ionicos basados en esqueletos de resorcinareno cavitando y/o esqueletos de naturaleza tripodal. Se estudiaron y analizadores los diferentes modos de interacción y las constantes de asociación hacia una gran variedad de guests de diferente naturaleza.
The present thesis is divided in two different parts. Part 1 is titled the importance of ligand design for the development of supramolecular catalysts. This part includes three different chapters: introduction chapter 1, chapter 2 and chapter 3. Chapter 1 shows a brief overview of the most interesting items related to supramolecular catalysis. In chapter 2 is described the synthesis and characterization of three different p-xylylbis-benzimidazolylidene iridium and rhodium complexes. Chapter 3 reports the synthesis, characterization and catalytic studies of different palladium, iridium and rhodium complexes, which are formed by N-heterocyclic ligands featuring different topologies, and some of them decorated with pyrene functionalities. The importance and influence of these ligands in the conformational and catalytic behaviour of the metal complexes is studied in detail, providing evidences of the effects produces due to non-covalent interactions such as π-π interactions. Part 2 is titled the importance of ligand design for the development of ion receptors. This part includes three chapters: introduction chapter 4, chapter 5 and chapter 6. Chapter 4 is a brief introduction of the most relevant aspects related to supramolecular host-guest chemistry. The approaches described in chapter 5 consist of two different strategies for the preparation of imidazole resorcinarene based cavitands for the recognition of anions or cations. Chapter 6 reports the synthesis of tris-azolium and tris-iodoazolium tripodal receptors for the recognition of anions. In both chapters (5 and 6) are studied the binding capabilities of the receptors towards several ions, showing the importance of the development in ligand design to improve the properties of the receptors.

Guo, Chris. "Alkane Oxidation Catalysis by Homogeneous and Heterogeneous Catalyst". Thesis, The University of Sydney, 2005. http://hdl.handle.net/2123/622.

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Abstract Cobalt-based complexes are widely used in industry and organic synthesis as catalysts for the oxidation of hydrocarbons. The Co/Mn/Br (known as "CAB system") catalyst system is effective for the oxidation of toluene. The Co/Mn/Br/Zr catalyst system is powerful for the oxidation of p-xylene, but not for the oxidation of toluene. [Co3O(OAc)5(OH)(py)3][PF6] (Co 3+ trimer 5) is more effective than [Co3O(OAc)6(py)3][PF6] (Co 3+ trimer 6) as a catalyst in the CAB catalyst system. Higher temperatures favour the oxidation of toluene. Zr 4+ does not enhance the oxidation of toluene. Zr 4+ could inhibit the oxidation of toluene in the combination of Co/Br/Zr, Co/Mn/Zr or Co/Zr. NHPI enhances the formation of benzyl alcohol, but the formation of other by-products is a problem for industrial processes. Complex(es) between cobalt, manganese and zirconium might be formed during the catalytic reaction. However, attempts at the preparation of complexes consisting of Co/Zr or Mn/Zr or Co3ZrP or Co8Zr4 clusters failed. The oxidation of cyclohexane to cyclohexanone and cyclohexanol is of great industrial significance. For the homogeneous catalysis at 50 o C and 3 bar N2 pressure, the activity order is: Mn(OAc)3 �2H2O > Mn12O12 cluster > Co 3+ trimer 6 > [Co3O(OAc)3(OH)2(py)5][PF6]2 (Co 3+ trimer 3) > Co 3+ trimer 5 > Co(OAc)2 �4H2O > [Co2(OAc)3(OH)2(py)4][PF6]-asym (Co dimerasym) > [Co2(OAc)3(OH)2(py)4][PF6]-sym (Co dimersym); whereas [Mn2CoO(OAc)6(py)3]�HOAc (Mn2Co complex) and zirconium(IV) acetate hydroxide showed almost no activity under these conditions. But at 120 o C and 3 bar N2 pressure, the activity order is changed to: Co dimerasym > Co(OAc)2 �4H2O > Co trimer 3 and Mn(OAc)3 �2H2O > Co 3+ trimer 6 > Mn2Co complex > Co 3+ trimer 5 > Co dimersym > Mn12O12 cluster. The molar ratio of the products was close to cyclohexanol/cyclohexanone=2/1. Mn(II) acetate and zirconium(IV) acetate hydroxide showed almost no activity under these conditions. Among those cobalt dimers and trimers, only the cobalt dimerasym survived after the stability tests, this means that [Co2(OAc)3(OH)2(py)4][PF6]-asym might be the active form for cobalt(II) acetate in the CAB system. Metal-substituted (silico)aluminophosphate-5 molecular sieves (MeAPO-5 and MeSAPO-5) are important heterogeneous catalysts for the oxidation of cyclohexane. The preparation of MeAPO-5 and MeSAPO-5 and their catalytic activities were studied. Pure MeAPO-5 and MeSAPO-5 are obtained and characterised. Four new pairs of bimetal-substituted MeAPO-5 and MeSAPO-5(CoZr, MnZr, CrZr and MnCo) were prepared successfully. Two novel trimetal-subtituted MeAPO-5 and MeSAPO-5 (MnCoZr) are reported here. Improved methods for the preparation of four monometal-substituted MeAPO-5 (Cr, Co, Mn and Zr) and for CoCe(S)APO-5 and CrCe(S)APO-5 are reported. Novel combinational mixing conditions for the formation of gel mixtures for Me(S)APO-5 syntheses have been developed. For the oxidation of cyclohexane by TBHP catalysed by MeAPO-5 and MeSAPO-5 materials, CrZrSAPO-5 is the only active MeSAPO-5 catalyst among those materials tested under conditions of refluxing in cyclohexane. Of the MeAPO-5 materials tested, whereas CrCeSAPO-5 has very little activity, CrZrAPO-5 and CrCeAPO-5 are very active catalysts under conditions of refluxing in cyclohexane. MnCoAPO-5, MnZrAPO-5 and CrAPO-5 are also active. When Cr is in the catalyst system, the product distribution is always cyclohexanone/cyclohexanol equals 2-3)/1, compared with 1/2 for other catalysts. For MeAPO-5, the activity at 150 o C and 10 bar N2 pressure is: CrZrAPO-5 > CrCeAPO-5 > CoZrAPO-5. For MeAPO-5 and MeSAPO-5, at 150 o C and 13 bar N2 pressure, the selectivity towards cyclohexanone is: CrZrAPO-5 > CrZrSAPO-5 > CrCeAPO-5 > CrAPO-5 > MnCoAPO-5 > MnZrAPO-5; and the selectivity towards cyclohexanol is: MnZrAPO-5 > CrZrAPO-5 > MnCoAPO-5 > CrZrSAPO-5 > CrCeAPO-5 > CrAPO-5. Overall the selectivity towards the oxidation of cyclohexane is: CrZrAPO-5 > CrZrSAPO-5 > CrCeAPO-5 > CrAPO-5 > MnCoAPO-5 > MnZrAPO-5. The amount of water in the system can affect the performance of CrCeAPO-5, but has almost no effect on CrZrAPO-5. Metal leaching is another concern in potential industrial applications of MeAPO-5 and MeSAPO-5 catalysts. The heterogeneous catalysts prepared in the present work showed very little metal leaching. This feature, coupled with the good selectivities and effectivities, makes them potentially very useful.

Guo, Chris. "Alkane Oxidation Catalysis by Homogeneous and Heterogeneous Catalyst". University of Sydney. Chemistry, 2005. http://hdl.handle.net/2123/622.

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Damian, Karen Serena. "Pd catalysed synthesis of phosphines for homogeneous catalysis". Thesis, St Andrews, 2009. http://hdl.handle.net/10023/907.

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Craig, Kim Meyer. "New concepts in catalyst design: homogeneous organometallic catalysts with tunable architectures". Thesis, University of Auckland, 2010. http://hdl.handle.net/2292/6114.

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This theses describes the development of homogeneous catalysts containing receptor elements which are capable of participating in reversible bonding interactions with groups bearing complementary functionality. This approach is amenable to combinatorial chemistry, and could facilitate catalyst development processes which are conventionally expensive and time-intensive. To date, the implication of reversible supra molecular interactions in anthropogenic organometallic catalysis are not widely understood.

Gao, Tianyu. "Hétérogénéisation de catalyseurs homogènes à l'aide de matériaux à structures organiques covalentes". Electronic Thesis or Diss., Centrale Lille Institut, 2022. http://www.theses.fr/2022CLIL0016.

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L'hétérogénéisation des catalyseurs homogènes est un moyen efficace pour réaliser leur réutilisation. Les matériaux à structures organiques covalentes (Covalent Organic Frameworks ou COF en anglais) sont des matériaux poreux prometteurs qui méritent d'être développés en raison de leur surface spécifique importante, de leur structure microporeuse et de leur stabilité thermique élevée pour jouer le rôle de structure hôte pour l'hétérogénéisation de catalyseurs homogènes. Dans cette thèse, l'acide phosphotungstique homogène (HPW) est hétérogénéisé via son encapsulation dans l'espacement intercouche du COF 2D CIN-1. Le catalyseur hétérogénéisé HPW@CIN-1 montre des activités catalytiques intéressantes et une grande stabilité dans les réactions modèles testées. D’une manière similaire, l'hétérogénéisation d’un complexe organique de Ru est obtenue via son encapsulation dans l'espacement intercouche du COF CIN-1 fonctionnalisé. Le catalyseur hétérogène Ru@CIN-1 obtenu présente une activité catalytique et une stabilité élevée dans des réactions modèles d'amination et d'hydrogénation. Afin d'élargir l'application du catalyseur Ru@CIN-1, ce dernier a été pyrolysé sous atmosphère inerte. Le nouveau matériau Ru@g-C3N4 ainsi obtenu démontre une excellente performance en électrocatalyse de l’eau. Enfin, le catalyseur Fe(NO3)3 homogène est hétérogénéisé par greffage sur un COF 2D bidentate substitué par des groupements hydroxyles (LZU1-OH). Le catalyseur Fe@LZU1-OH obtenu présente une activité et une stabilité supérieures dans les réactions modèles d'oxydation testées par rapport au catalyseur homogène parent
Heterogenization of homogeneous catalysts is an effective way to combine highactivity, selectivity and recyclability of catalysts. Covalent Organic Frameworks (COF) are promising organic porous materials that are worthy to be developed as host structures for the heterogenization of homogeneous catalysts, due to their high specific surface area, microporous structure, easy functionalization and high thermal stability. In this thesis, homogeneous phosphotungstic acid (HPW) is heterogenized via encapsulation into the interlayer spacing of 2D COF CIN-1. The heterogenized HPW@CIN-1 catalyst shows high catalytic activities and stability in acid-catalyzed reactions. Heterogenization of homogeneous Ru ions is achieved via tethering by diphenylphosphinobenzaldehyde ligand in the interlayer spacing of CIN-1. The obtained heterogenous Ru@CIN-1 catalyst shows high catalytic activity and stability in model reactions of amination and hydrogenation. In order to widen the application of Ru@CIN-1 catalyst, it has been pyrolyzed under inert atmosphere to obtain Ru supported over carbon nitride material. The obtained novel Ru@g-C3N4 material demonstrates a super performance in electrocatalytic water splitting. Homogeneous Fe(NO3)3 catalyst is heterogenized via grafting to hydroxyl-substituted bidentate 2D COF LZU1 (LZU1-OH). The obtained Fe@LZU1-OH catalyst shows high activity in oxidation model reactions comparable to the parent homogeneous catalyst at high stability

Richardson, John Michael. "Distinguishing between surface and solution catalysis for palladium catalyzed C-C coupling reactions: use of selective poisons". Diss., Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22704.

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This work focuses on understanding the heterogeneous/homogeneous nature of the catalytic species for a variety of immobilized metal precatalysts used for C-C coupling reactions. These precatalysts include: (i) tethered organometallic palladium pincer complexes, (ii) an encapsulated small molecule palladium complex in a polymer matrix, (iii) mercapto-modified mesoporous silica metalated with palladium acetate, and (iv) amino-functionalized mesoporous silicas metalated with Ni(II). As part of this investigation, the use of metal scavengers as selective poisons of homogeneous catalysis is introduced and investigated as a test for distinguishing heterogeneous from homogeneous catalysis. The premise of this test is that insoluble materials functionalized with metal binding sites can be used to selectively remove soluble metal, but will not interfere with catalysis from immobilized metal. In this way the test can definitely distinguish between surface and solution catalysis of immobilized metal precatalysts. This work investigates three different C-C coupling reactions catalyzed by the immobilized metal precatalysts mentioned above. These reactions include the Heck, Suzuki, and Kumada reactions. In all cases it is found that catalysis is solely from leached metal. Three different metal scavenging materials are presented as selective poisons that can be used to determine solution vs. surface catalysis. These selective poisons include poly(vinylpyridine), QuadrapureTM TU, and thiol-functionalized mesoporous silica. The results are contrasted against the current understanding of this field of research and subtleties of tests for distinguishing homogeneous from heterogeneous catalysis are presented and discussed.

Schätz, Alexander. "Immobilization of homogeneous catalysts on nanoparticles and their application in semi-heterogeneous catalysis". kostenfrei, 2009. http://www.opus-bayern.de/uni-regensburg/volltexte/2009/1239/.

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Martins, Tânia Isabel Quintas. "Continuous flow homogeneous catalysis using ionic liquid/supercritical fluid biphasic systems". Thesis, University of St Andrews, 2010. http://hdl.handle.net/10023/982.

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Ionic liquid/scCO₂ biphasic systems have been studied as a possible solution to the main problems concerning homogeneous catalysis reactions such as, the product/catalyst separation, the catalyst retention in the reaction medium and the use of organic solvents. The hydroformylation of long chain alkenes (1-octene) has been carried out as a continuous flow reaction using [OctMIM]Tf₂N (OctMIM = 1-octyl-3-methylimidazolium, Tf = CF₃SO₂) as the reaction solvent and scCO₂as the mobile phase to extract the products. The performance of the rhodium complexes formed with the ionic ligands [PentMIM][TPPTS] (1-pentyl-3- methylimidazolium tri(m-sulfonyl)triphenylphosphine) and [OctMIM][TPPTS] (1-octyl-3- methylimidazolium tri(m-sulfonyl)triphenylphosphine) is described under different sets of experimental conditions. Continuous flow hydroformylation of 1-octene was also carried out using a SILP (Supported Ionic Liquid Phase) catalyst formed with the TPPTS-based ionic ligands named above. The SILP system described in this work has the peculiarity of introducing the “without gases” approach: syn gas was synthesised in situ by the decomposition of formaldehyde. The performance of both systems is compared in the end. The extension of the continuous flow ionic liquid/scCO₂ biphasic system is shown with the optimisation of the silver-catalysed heterocyclisation of furans. A comparison is carried out with a previously developed and optimised continuous flow heterogeneous system.

Lummiss, Justin Alexander MacDonald. "Olefin Metathesis: Life, Death, and Sustainability". Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32277.

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Over the past 15 years, ruthenium-catalyzed olefin metathesis has emerged as a cornerstone synthetic methodology in academia. Applications in fine-chemicals and pharmaceutical manufacturing, however, are just beginning to come on stream. Industrial uptake has been impeded by economic constraints associated with catalyst costs. These are due both to direct costs (exacerbated by intellectual property issues), and to further pressure exerted by the low turnover numbers attainable, and the need for extensive purification to remove ruthenium residues. From another perspective, however, these difficulties can be seen as arising from our rudimentary understanding of the fundamental organometallic chemistry of the Ru=CHR bond. In particular, we know little about the nature and reaction pathways of the Ru-methylidene unit present in the active species that propagates metathesis, and in the catalyst resting state. We know slightly more about the ruthenacyclobutane species, but still too little to guide us as to their non-metathetical reaction pathways, their contribution to deactivation relative to the methylidene species, and potential work-arounds. This thesis work was aimed at improving our understanding of the reactivity, speciation, and decomposition of key ruthenium intermediates in olefin metathesis. A major focus was the behaviour and deactivation of species formed from the second-generation Grubbs catalyst RuCl2(H2IMes)(PCy3)(=CHPh) (S-GII), which dominates ring-closing metathesis. Also studied were derivatives of the corresponding IMes catalyst A-GIIm, containing an unsaturated Nheterocyclic carbene (NHC) ligand. The methylidene complexes RuCl2(NHC)(PCy3)(=CH2) (GIIm) represent the resting state of the catalyst during ring-closing and cross-metathesis reactions: that is, the majority Ru species present during catalysis. Mechanistic studies of these key intermediates have been restricted, however, by the low yields and purity with which they could be accessed. Initial work therefore focused on designing a clean, high-yield route to the second-generation Grubbs methylidene complexes S-GIIm and A-GIIm. These routes were subsequently expanded to develop access to isotopically-labelled derivatives. Locating a 13C-label at the key alkylidene site, in particular, offers a powerful means of tracking the fate of the methylidene moiety during catalyst deactivation. Access to GIIm enabled detailed studies of the behaviour and decomposition of the Grubbs catalysts. First, the long-standing question of the impact of saturation of the NHC backbone (i.e. IMes vs. H2IMes) was examined. Dramatic differences in the behaviour of the two complexes were traced to profound differences in PCy3 lability arising from the diminished π-acidity of the IMes ligand. Secondly, the vulnerability of GIIm to nucleophiles was examined. This is an important issue from the perspective of decomposition by adventitious nucleophiles in the reaction medium during catalysis, but also reflects on substrate scope. For amine additives, the dominant deactivation pathway was shown to typically involve attack on the resting-state methylidene complex, not the metallacyclobutane, which has often been regarded as the most vulnerable intermediate. In addition, the sigma-alkyl intermediate formed by nucleophilic attack of displaced phosphine at the methylidene carbon was trapped by moving to the first-generation complex, and using a nitrogen donor (pyridine) that cannot promote decomposition via N–H activation pathways. Interception of this long-suspected species led to the proposal of “donorinduced” deactivation as a general decomposition pathway for Grubbs-class catalysts. Finally, the capacity of phosphine-free catalysts to overcome the shortcomings of the secondgeneration Grubbs catalysts was demonstrated, in a case study involving application of crossmetathesis (CM) to the synthesis of a high-value antioxidant. An efficient CM methodology was developed for the reaction of renewable essential-oil phenylpropenoids with vinyl acrylates. This work illustrates a new paradigm in sustainable metathesis. Rather than degrading unsaturated feedstocks via metathesis (a process that can be termed “metathe[LY]sis”), it demonstrates how metathesis with directly-functionalized olefins can be used to augment structure and function. From the perspective of organometallic chemistry and catalyst design, key comparisons built into this thesis are the effect of the NHC ligand (IMes vs. H2IMes) and its trans ancillary ligand on the efficient entry into catalysis; the susceptibility to nucleophilic attack of the alkylidene ligand (benzylidene vs. methylidene) vs. the metallacyclobutane; and the effect of replacing a phosphine ancillary ligand with a non-nucleophilic donor. From a practical standpoint, Chapter 2 brings new life to metathesis with the high-yield synthesis of the resting state species, Chapters 3 and 4 examine the deactivation, or death, of the methylidene complexes, and Chapter 5 establishes a new paradigm for olefin metathesis within the context of sustainable synthesis.

Più fonti

Libri sul tema "Homogenous catalysts":

Griffith, W. P. Ruthenium oxidation complexes: Their uses as homogenous organic catalysts. Dordrecht: Springer Science+Business Media, 2011.

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Yamaguchi, Ryohei. Ligand platforms in homogenous catalytic reactions with metals: Practice and applications for green organic transformations. Hoboken, New Jersey: Wiley, 2015.

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de, Vries Johannes G., e Elsevier Cornelis J, a cura di. The handbook of homogeneous hydrogenation. Weinheim: Wiley-VCH, 2007.

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van Leeuwen, Piet W. N. M., e John C. Chadwick. Homogeneous Catalysts. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527635993.

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Bhaduri, Sumit, e Doble Mukesh. Homogeneous Catalysis. Hoboken, NJ: John Wiley & Sons, Inc, 2014. http://dx.doi.org/10.1002/9781118872369.

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van Leeuwen, Piet W. N. M. Homogeneous Catalysis. Dordrecht: Springer Netherlands, 2004. http://dx.doi.org/10.1007/1-4020-2000-7.

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Behr, Arno. Applied homogeneous catalysis. Weinheim: Wiley-VCH, 2012.

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Slaughter, LeGrande M., a cura di. Homogeneous Gold Catalysis. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-13722-3.

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1934-, Morokuma K., e Musaev Djamaladdin G, a cura di. Computational modeling for homogeneous and enzymatic catalysis: A knowledge-base for designing efficient catalysts. Weinheim: Wiley-VCH, 2008.

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A, Chaloner Penny, a cura di. Homogeneous hydrogenation. Dordrecht: Kluwer Academic Publishers, 1994.

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Capitoli di libri sul tema "Homogenous catalysts":

Kirchhecker, Sarah, Brian Spiegelberg e Johannes G. de Vries. "Homogenous Iridium Catalysts for Biomass Conversion". In Iridium Catalysts for Organic Reactions, 341–95. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/3418_2020_72.

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Wu, Lei, Ji Liu, Baode Ma e Qing-Hua Fan. "Homogeneous Asymmetric Catalysis Using Immobilized Chiral Catalysts". In Bridging Heterogeneous and Homogeneous Catalysis, 111–48. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2014. http://dx.doi.org/10.1002/9783527675906.ch4.

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Mecking, Stefan. "Homogeneous Catalysis with Soluble Polymer-Bound Catalysts as a Unit Operation". In Multiphase Homogeneous Catalysis, 765–75. Weinheim, Germany: Wiley-VCH Verlag GmbH, 2008. http://dx.doi.org/10.1002/9783527619597.ch7c.

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Kaminsky, W., e R. Kramolowsky. "Homogeneous Catalysts". In Inorganic Reactions and Methods, 309–11. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470145319.ch115.

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Bouwman, Elisabeth, Martin C. Feiters e Robertus J. M. Klein Gebbink. "Homogeneous Catalysis". In Catalysis, 73–125. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2017. http://dx.doi.org/10.1002/9783527810932.ch3.

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Mathey, Francois. "Homogeneous Catalysis". In SpringerBriefs in Molecular Science, 57–83. Singapore: Springer Singapore, 2013. http://dx.doi.org/10.1007/978-981-4451-09-3_3.

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Somorjai, G. A., e M. Salmeron. "Surface Properties of Catalysts. Iron and Its Oxides; Surface Chemistry, Photochemistry And Catalysis". In Homogeneous and Heterogeneous Photocatalysis, 445–77. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-4642-2_27.

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Ouali, Armelle, e Anne-Marie Caminade. "Terminal Groups of Dendrimers as Catalysts for Homogeneous Catalysis". In Dendrimers, 163–82. Chichester, UK: John Wiley & Sons, Ltd, 2011. http://dx.doi.org/10.1002/9781119976530.ch7.

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A. Alsaiari, Raiedhah. "Ruthenium Catalyst for Epoxidation Reaction". In Ruthenium - an Element Loved by Researchers [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.96466.

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Abstract (sommario):

The role of ruthenium as a heterogeneous catalyst for epoxidation reaction has not been investigated extensively. Therefore, the purpose of this chapter is to provide overview of the epoxidation of alkene using ruthenium catalysts. The chapter is divided into two main sections. The first section is about epoxidation of alkene using supported ruthenium catalysts, while the second using ruthenium complexes (homogenous catalysts).

"Catalysis and Green Chemistry". In Green Chemistry: An Introductory Text, 95–146. 3^a ed. The Royal Society of Chemistry, 2016. http://dx.doi.org/10.1039/9781782622949-00095.

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Catalysis is of fundamental importance to green chemistry. Illustrated by many industry examples, the benefits and limitations of both heterogeneous and homogeneous catalysts are reviewed. The increasing importance of specific catalyst types such as biocatalysts and phase-transfer catalysts is discussed.

Atti di convegni sul tema "Homogenous catalysts":

Willetts, D. V., e M. R. Harris. "Homogeneous Catalysis for CO2 Lasers". In Coherent Laser Radar. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/clr.1991.mc2.

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The attainment of long sealed gas lifetimes is one of the few outstanding areas of carbon dioxide laser technology which need to be addressed. Electron impact dissociation of carbon dioxide can be overcome by use of a catalyst to recombine the carbon monoxide and oxygen so formed. Heterogeneous catalysts have been extensively studied; although effective, such catalysts necessarily introduce problems of dust release in a vibrating environment and impedance to gas flow. In addition, attention must be paid to isotopic exchange between catalyst and gas. These difficulties disappear if a suitable homogenous catalyst can be found.

Kafuku, Gerald, Makme Mbarawa, Man Kee Lam e Keat Teong Lee. "Optimized Preparation of Moringa Oleifera Methyl Esters Using Sulfated Tin Oxide as Heterogenous Catalyst". In ASME 2010 4th International Conference on Energy Sustainability. ASMEDC, 2010. http://dx.doi.org/10.1115/es2010-90503.

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Fatty acid methyl esters (biodiesel), prepared from transesterification of vegetable oils or animal fats, have gained great importance in substituting petroleum based diesel for combating environmental problems and higher diesel prices. Moringa oleifera fatty acids are among the newly investigated potentials for biodiesel production in recent years. In getting rid of soap formation and thus large waste washing water from biodiesel produced from homogenous catalysts, the use of heterogeneous catalysts is currently preferred due to easily separation and purification of the final products. In this study, biodiesel was produced from moringa oleifera oil using sulfated tin oxide enhanced with SiO2 (SO42−/SnO2−SiO2) as super acid solid catalyst. The experimental design was done using design of experiment (DoE), specifically, response surface methodology based on three-variable central composite design (CCD) with alpha (α) = 2. The reaction parameters in the optimization process were reaction temperature (60°C to 180°C), reaction period (1 to 3 hrs) and methanol to oil ratio (1:6 to 1:24 mol/mol). It was observed that the yield up to 84wt% of moringa oleifera methyl esters can be obtained with reaction conditions of 150°C temperature, 150 minutes reaction time and 1:19.5 methanol to oil ratio, while catalyst concentration and agitation speed are kept at 3wt% and 350 rpm respectively.

Wong, Bunsen, Dennis Thomey, Lloyd Brown, Martin Roeb, Robert Buckingham e Christian Sattler. "Sulfur Based Thermochemical Energy Storage for Concentrated Solar Power". In ASME 2013 7th International Conference on Energy Sustainability collocated with the ASME 2013 Heat Transfer Summer Conference and the ASME 2013 11th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/es2013-18283.

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A sulfur based thermochemical energy storage cycle for baseload power generation is being developed under the support of US DOE Sunshot program. Solar heat is stored in elemental sulfur via thermal decomposition of sulfuric acid and disproportionation of sulfur dioxide into elemental sulfur and sulfuric acid. Heat energy is recovered upon sulfur combustion. On-sun decomposition of sulfuric acid in a solar furnace has been demonstrated between 650 and 850°C. Near equilibrium conversion was obtained at high temperature but conversion was reduced due to catalyst poisoning at the lower temperatures. Sulfur dioxide disproportionation modeling showed the reaction driving force is maximized at the high system pressure and low system temperature. The effect of system pressure was validated experimentally. However, the disproportionation rate was found to increase with system temperature as a result of increased reaction kinetics. Homogenous iodide catalysts were used to further enhance the degree of disproportionation and the reaction rate. The process steps required to recover the catalyst for reuse have been verified.

Askarova, A. G., K. V. Maerle, E. Y. Popov, S. E. Malaniy, P. A. Grishin, O. V. Slavkina e A. N. Cheremisin. "Perspectives of Hydrogen Peroxide Injection to the Carbonate Reservoir for ISC Initiation". In ADIPEC. SPE, 2023. http://dx.doi.org/10.2118/216649-ms.

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Abstract As part of laboratory and numerical investigations, an assessment of hydrogen peroxide (H2O2) injection efficiency was performed to estimate the ability of H2O2 to increase the productivity of heavy oil field development. The combined effect can be observed, including heat release due to H2O2 decomposition and oxidative reactions with oil during the in situ combustion (ISC) process and increased oil mobility due to CO2 dissolution. Laboratory experiments were performed on an autoclave to study the decomposition of peroxide in conditions close to the reservoir (pressure and temperature) and obtain experimental values of the kinetic parameters of the H2O2 decomposition reaction. Further, these values and experimental parameters were integrated into a homogenous numerical model representing the target oil reservoir. Also, during the laboratory experiment, the optimal value of the H2O2 concentration was determined for subsequent sensitivity analysis. The numerical model was then used to build a Tornado diagram and to estimate the effects of preheating, operational parameters, reservoir properties and kinetic parameters with or without catalysts in the system. According to the results of the hydrodynamic modeling, efficient heating of the formation to high temperatures (over 100°C) during the injection and decomposition of H2O2 is possible only in the presence of a catalyst. The bottomhole formation zone temperature with a catalyst can reach up to 350°C. The most significant influence on the cumulative production is provided by the injection rate, reservoir permeability, initial temperature of the injecting fluid, as well as the thermal properties of the rock. When the temperature reaches 300°C, the reaction of peroxide decomposition begins to accompany the ISC of oil, which is self-initiated, since there is a sufficient amount of oxygen in the formation formed during the decomposition of H2O2. An effective application of the technology is possible during a sufficiently fast rate of the peroxide decomposition to avoid the dissipation of the released heat due to two possible mechanisms: heating (up to ~150°С) of injected agent (effective, but it is associated with additional costs for equipment and technological risks);use of widely available and cheap catalysts. As a result of the work, the most promising strategies of H2O2 injection technology for heating a carbonate reservoir were identified. The option of full-scale injection of the H2O2 is associated with high costs and limited development rates. This method can be applied to objects with specific conditions of elevated temperatures where the peroxide decomposition reaction will be the most active.

Wüthrich, Kurt, R. H. Grubbs, T. Visart de Bocarmé e Anne De Wit. "Homogeneous Catalysis". In 24th International Solvay Conference on Chemistry. WORLD SCIENTIFIC, 2018. http://dx.doi.org/10.1142/9789813237179_others01.

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GRUBBS, ROBERT H. "HOMOGENEOUS CATALYSIS: ORGANOMETALLIC CATALYSIS AND ORGANOCATALYSIS". In 24th International Solvay Conference on Chemistry. WORLD SCIENTIFIC, 2018. http://dx.doi.org/10.1142/9789813237179_0001.

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Moser, Bryan, Kenneth Doll e Michael Jackson. "Serendipitous production of industrially useful p-cymene by catalytic dehydration and isomerization of perillyl alcohol". In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/ehhi6828.

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As part of our continuing efforts to produce aliphatic polyesters from fats and oils, we were originally attempting to esterify 9-decenoic acid with perillyl alcohol [(4-isopropenyl-1-cyclohexen-1-yl)methanol] in the presence of catalytic para-toluenesulfonic acid in refluxing toluene to give tris-unsaturated perillyl decenoate as a monomer for subsequent ADMET and thiol-ene polymerization. The esterification procedure had proven simple and effective for several previous esterifications involving different alcohol/acid combinations, but in this case the expected ester was not observed. Instead, a mixture comprised of unreacted perillyl alcohol and 9-decenoic acid and an unexpected and curiously high amount of p-cymene (31%; 4-isopropyltoluene) was obtained. With this serendipitous discovery in hand, we set out to improve the yield of industrially useful p-cymene from perillyl alcohol utilizing homogenous acid catalysis.Â We thus report the dehydration and isomerization of renewable perillyl alcohol as a 3.0 M solution in refluxing toluene to p-cymene in 91.1% yield utilizing catalytic para-toluenesulfonic acid. This approach represents a bio-based alternative to the conventional petrochemical Friedel-Crafts alkylation of toluene with propylene, which has several significant drawbacks. Industrial applications of p-cymene include use as a green solvent, heat transfer medium, ligand for catalysts, starting material for other industrial chemicals, and as a constituent in fragrances and perfumes.

CARREIRA, ERICK M. "HOMOGENEOUS CATALYSIS IN THE FUTURE". In 24th International Solvay Conference on Chemistry. WORLD SCIENTIFIC, 2018. http://dx.doi.org/10.1142/9789813237179_0006.

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Macchioni, Alceo. "Homogeneous and heterogenized iridium water oxidation catalysts". In SPIE Solar Energy + Technology, a cura di Sanjay Mathur. SPIE, 2014. http://dx.doi.org/10.1117/12.2060957.

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Dutta, P., D. K. Yee e R. A. Dalla Betta. "Catalytic Combustor Development for Ultra-Low Emissions Industrial Gas Turbines". In ASME 1997 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/97-gt-497.

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The goal of the Advanced Turbine Systems (ATS) program is to develop a high thermal efficiency industrial gas turbine with ultra-low emissions (<10 ppmv NOx, CO and UHC @ 15% O2) over the 50 to 100% load range. Catalytic combustion was chosen as an approach likely to meet ATS emissions goals. A subscale catalytic combustor development program was designed to develop a technical knowledge base for catalyst design (catalyst construction, length), performance (ignition, activity and emissions) and operating limitations (fuel-air turndown and sensitivity to combustor operating variables). A novel catalyst design with preferential catalyst coating to limit substrate temperatures was used in the tests. The catalytic combustor consists of a fuel-air premixer, catalytic reactor and a post-catalyst zone for completion of homogeneous gas phase reactions. In situ measurements of mean fuel concentrations at the exit of the premixer were completed to characterize fuel-air premixing levels. Performance of the catalyst was monitored through global emissions measurements at the exit of the post-catalyst combustor under simulated engine conditions, and measurement of catalyst substrate temperatures. Ultra-low emissions were achieved for relatively uniform fuel-air premixing (<10% peak to peak variation in fuel concentration) with higher inhomogeneities (>10% peak to peak variation) leading to either locally high or low substrate temperatures. Regions with low substrate temperatures led to high CO and UHC emissions. Modeling of post-catalyst homogeneous reactions using a standard stationary, one-dimensional, laminar premixed flame formulation showed good agreement with measurements. In short term tests, the catalysts showed the desired chemical activity and ability for multiple light-off. The subscale combustor development work provided the necessary technical information for full scale catalytic combustion system development for the ATS gas turbine.

Rapporti di organizzazioni sul tema "Homogenous catalysts":

Wayne Tikkanen. Homogeneous and Supported Niobium Catalysts as Lewis Acid and Radical Catalysts. Office of Scientific and Technical Information (OSTI), dicembre 2006. http://dx.doi.org/10.2172/922133.

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Landis, Clark R. Mechanisms and Design in Homogeneous Catalysis. Office of Scientific and Technical Information (OSTI), maggio 2010. http://dx.doi.org/10.2172/979723.

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Ye, Rong. Development of Molecular Catalysts to Bridge the Gap between Heterogeneous and Homogeneous Catalysts. Office of Scientific and Technical Information (OSTI), settembre 2017. http://dx.doi.org/10.2172/1488417.

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Earl, W. L., K. C. Ott, K. A. Hall, F. M. de Rege, D. K. Morita, W. Tumas, G. H. Brown e R. D. Broene. Heterogenization of Homogeneous Catalysts: the Effect of the Support. Office of Scientific and Technical Information (OSTI), giugno 1999. http://dx.doi.org/10.2172/763894.

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Stanger, Keith James. Studies of Immobilized Homogeneous Metal Catalysts on Silica Supports. Office of Scientific and Technical Information (OSTI), gennaio 2003. http://dx.doi.org/10.2172/815768.

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Miller, R., e R. Baldwin. Low severity coal liquefaction using homogeneous basic nitrogen catalysts. Office of Scientific and Technical Information (OSTI), agosto 1990. http://dx.doi.org/10.2172/6678814.

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Marks, Tobin J., Madelyn M. Stalzer e Massimiliano Delferro. Supported Organometallic Complexes: Surface Chemistry, Spectroscopy, Catalysis, and Homogeneous Models. Office of Scientific and Technical Information (OSTI), settembre 2016. http://dx.doi.org/10.2172/1325016.

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Laine, R. M., B. J. Wood e G. N. Krishnan. Low temperature, sulfur tolerant homogeneous catalysts for the water-gas shift reaction. Office of Scientific and Technical Information (OSTI), aprile 1986. http://dx.doi.org/10.2172/7205415.

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Hascall, Anthony G., e Richard Alan Kemp. LDRD final report on new homogeneous and supported oligomerization catalysts (LDRD 42461). Office of Scientific and Technical Information (OSTI), novembre 2004. http://dx.doi.org/10.2172/920453.

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Laine, R. M. Low temperature, sulfur tolerant homogeneous catalysts for the water-gas shift reaction. Office of Scientific and Technical Information (OSTI), gennaio 1986. http://dx.doi.org/10.2172/5128236.

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