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Catalysts heterogenized

Catalysts derived from CpTaCli, are also able to dimerise ethylene to 1-butene. (C5Me5)2MMc2 (M = Th.O) on AI2O3 are considerably better propene hydrogenation catalysts than CP3M-R derivatives they are converted to hydrides. Ethylene is polymerised.  [Pg.389]

A considerable effort has been expended in the heterogenization of homogeneous catalysts. A particular benefit would be that facile catalyst/product separation could be achieved which could have commercial significance in the hydroformylation of high boiling point or thermally unstable alkenes. At the same time it is desirable that these catalysts have similar activities and equivalent or better selectivities than their homogeneous counterparts. While diffusion presents a drawback with respect to activity it may be [Pg.184]

8 Alkoie and Alkyne Oligomerizatimi, Polymaization, and Co-oligomerizatirai Reactkms [Pg.419]

Alkenes.— A text on Ziegler-Natta catalysts has been published and polymerization by transition-metal hydrides, alkyls, and allyl compounds heis been reviewed. A reaction model for Ziegler-Natta polymerization has also been formulated. The conventional mechanism for alkene dimerization, oligomerization, and polymerization has, however, been questioned because there are no unambiguous examples of metal-alkyl-alkene compounds which unda go alkene insertion into the metal-alkyl bond. Also, catalysts which effect Ziegler-Natta polymerization are often active for alkene metathesis reactions and so a similiar mechanism for both has been proposed (Schrane 2).  [Pg.419]

1 (a) J. Boor jun., Ziegler-Natta Catalysts and Polymerizations Academic Press, New York, 1978 (b) A. Yamamoto and T. Yamamoto, Macromol. Rev., 1978,13, 161. [Pg.419]

A catalyst for the selective cyclodimerization of butadiene to 4-vinylcyclo-hexene can be generated by the reduction of [Fe(NO)2Cl], with metal carbonyls or electrochemically. Addition of cyclic amines to the isoprene dimerization catalyst [NiCl2(PPhs)2]-NaBH4-H20 enhances the formation of cyclic dimers the product distribution has been correlated with an electronic and structural properties of the amine. [Ni P(n-OC6H4R)3 J (R = Ph or SiMes) catalyses the selective (95 %) dimerization of butadirae to cyclo-octa-1,5-diene the catalysts appear to operate via two active centres, probably the Ni and P atoms. When solutions of (44) are allowed to stand and then treated with HCl or Brj signficant amounts of [1,1,3,3- H4]- and [2,2,3,3- H4]-butane are produced in addition to the anticipated [1,1,4,4- H4]-isomer. This would seem to indicate that there is an equilibrium (14) and in keeping with this (44) [Pg.420]

Schuchardt, F. Dos Santos, and F. Pedro, Cienc. Cult Sao Paulo), 1978, 30, 161. [Pg.421]


In general, heterogeneous catalysts are preferred to homogeneous catalysts because the separation and recycling of homogeneous catalysts often can be very difficult. Loss of homogeneous catalyst not only creates a direct expense through loss of material but also creates an environmental problem. [Pg.46]

Heterogeneous catalysts. In heterogeneous catalysis, the catalyst is in a different phase from the reacting species. Most often, the... [Pg.46]

Heterogeneous catalysts are more common. However, they degrade and need replacement. If contaminants in the feed material or recycle shorten catalyst life, then extra separation to remove these contaminants before the feed enters the reactor might be justified. If the cataylst is sensitive to extreme conditions, such as high temperature, then some measures can help to avoid local hot spots and extend catalyst life ... [Pg.279]

Reducing catalyst waste by changing from homogeneous to heterogeneous catalysts and protecting catalysts from contaminants and extreme conditions that will shorten their life. [Pg.297]

M. Boudart, Supported Metals as Heterogeneous Catalysts, the Science of Precious Metals Applications, International Precious Metals Institute, Allentown, PA, 1989. [Pg.744]

Aqueous solutions of hydrogen peroxide decompose slowly the decomposition is catalysed by alkalis, by light and by heterogeneous catalysts, for example dust, platinum black and manganese... [Pg.279]

XJsorption of gases on to transition metal surfaces is important, and transition metals or alloys are often used as heterogeneous catalysts. [Pg.369]

Heating butanediol or tetrahydrofuran with ammonia or an amine in the presence of an acidic heterogeneous catalyst gives pyrroHdines (135,136). With a dehydrogenation catalyst, one or both of the hydroxyl groups are replaced by amino groups (137). [Pg.108]

Hydrogenolysis Process. Patty alcohols are produced by hydrogenolysis of methyl esters or fatty acids ia the presence of a heterogeneous catalyst at 20,700—31,000 kPa (3000—4500 psi) and 250—300°C ia conversions of 90—98%. A higher conversion can be achieved using more rigorous reaction conditions, but it is accompanied by a significant amount of hydrocarbon production. [Pg.446]

Reduction Reactions. Aldehydes can be hydrogenated to the corresponding alcohol using a heterogeneous catalyst, for example... [Pg.470]

Very extensive investigations have been conducted on the oxidation of methane over a number of heterogeneous catalysts, particularly —MgO... [Pg.341]

MIBK Direct Conversion ofMcetone over Heterogeneous Catalyst-Sumitomo, Process Evaluation Research Planning (PERP), Topical Reports, Vol. Ill, Chem Systems Inc., Tarrytown, NY, 1988. [Pg.502]

Butane-Based Fixed-Bed Process Technology. Maleic anhydride is produced by reaction of butane with oxygen using the vanadium phosphoms oxide heterogeneous catalyst discussed earlier. The butane oxidation reaction to produce maleic anhydride is very exothermic. The main reaction by-products are carbon monoxide and carbon dioxide. Stoichiometries and heats of reaction for the three principal reactions are as follows ... [Pg.455]

Most catalysts for solution processes are either completely soluble or pseudo-homogeneous all their catalyst components are introduced into the reactor as Hquids but produce soHd catalysts when combined. The early Du Pont process employed a three-component catalyst consisting of titanium tetrachloride, vanadium oxytrichloride, and triisobutjlalurninum (80,81), whereas Dow used a mixture of titanium tetrachloride and triisobutylalurninum modified with ammonia (86,87). Because processes are intrinsically suitable for the use of soluble catalysts, they were the first to accommodate highly active metallocene catalysts. Other suitable catalyst systems include heterogeneous catalysts (such as chromium-based catalysts) as well as supported and unsupported Ziegler catalysts (88—90). [Pg.387]

Supported aqueous phase (SAP) catalysts (16) employ an aqueous film of TPPTS or similar ligand, deposited on a soHd support, eg, controlled pore glass. Whereas these supported catalysts overcome some of the principal limitations experienced using heterogeneous catalysts, including rhodium leaching and rapid catalyst deactivation, SAP catalysts have not found commercial appHcation as of this writing. [Pg.469]

In the early 1950s, Ziegler observed that certain heterogeneous catalysts based on transition metals polymerized ethylene to a linear, high density material at modest pressures and temperatures. Natta showed that these catalysts also could produce highly stereospecific poly-a-olefins, notably isotactic polypropylene, and polydienes. They shared the 1963 Nobel Prize in chemistry for their work. [Pg.437]

The MTDP process, which is similar to the Tatoray process, produces an equilibrium composition of xylene isomers. A -xylene yield of 24% in the xylene product is formed at 42—48 wt % toluene conversion over the heterogeneous catalyst at 390—495°C, 4.2 MPa (600 psig), 1 2 Hquid hourly space velocity, and 4 H2/hydrocarbon molar feed ratio. A new ZSM-5 catalyst, which has higher activity and stability than the current catalyst, has been reported (93). [Pg.53]

Homogeneous and heterogenous catalysts which selectively or partially hydrogenate fatty amines have been developed (50). Selective hydrogenation of cis and trans isomers, and partial hydrogenation of polyunsaturated moieties, such as linoleic and linolenic to oleic, is possible. [Pg.220]

The tert-huty hydroperoxide is then mixed with a catalyst solution to react with propylene. Some TBHP decomposes to TBA during this process step. The catalyst is typically an organometaHic that is soluble in the reaction mixture. The metal can be tungsten, vanadium, or molybdenum. Molybdenum complexes with naphthenates or carboxylates provide the best combination of selectivity and reactivity. Catalyst concentrations of 200—500 ppm in a solution of 55% TBHP and 45% TBA are typically used when water content is less than 0.5 wt %. The homogeneous metal catalyst must be removed from solution for disposal or recycle (137,157). Although heterogeneous catalysts can be employed, elution of some of the metal, particularly molybdenum, from the support surface occurs (158). References 159 and 160 discuss possible mechanisms for the catalytic epoxidation of olefins by hydroperoxides. [Pg.138]

EBHP is mixed with a catalyst solution and fed to a horizontal compartmentalized reactor where propylene is introduced into each compartment. The reactor operates at 95—130°C and 2500—4000 kPa (360—580 psi) for 1—2 h, and 5—7 mol propylene/1 mol EBHP are used for a 95—99% conversion of EBHP and a 92—96% selectivity to propylene oxide. The homogeneous catalyst is made from molybdenum, tungsten, or titanium and an organic acid, such as acetate, naphthenate, stearate, etc (170,173). Heterogeneous catalysts consist of titanium oxides on a siUca support (174—176). [Pg.140]

It is carried out in the Hquid phase at 100—130°C and catalyzed by a soluble molybdenum naphthenate catalyst, also in a series of reactors with interreactor coolers. The dehydration of a-phenylethanol to styrene takes place over an acidic catalyst at about 225°C. A commercial plant (50,51) was commissioned in Spain in 1973 by Halcon International in a joint venture with Enpetrol based on these reactions, in a process that became known as the Oxirane process, owned by Oxirane Corporation, a joint venture of ARCO and Halcon International. Oxirane Corporation merged into ARCO in 1980 and this process is now generally known as the ARCO process. It is used by ARCO at its Channelview, Texas, plant and in Japan and Korea in joint ventures with local companies. A similar process was developed by Shell (52—55) and commercialized in 1979 at its Moerdijk plant in the Netherlands. The Shell process uses a heterogeneous catalyst of titanium oxide on siHca support in the epoxidation step. Another plant by Shell is under constmction in Singapore (ca 1996). [Pg.484]


See other pages where Catalysts heterogenized is mentioned: [Pg.47]    [Pg.48]    [Pg.279]    [Pg.729]    [Pg.898]    [Pg.2789]    [Pg.101]    [Pg.77]    [Pg.490]    [Pg.9]    [Pg.265]    [Pg.241]    [Pg.126]    [Pg.478]    [Pg.488]    [Pg.489]    [Pg.489]    [Pg.106]    [Pg.507]    [Pg.474]    [Pg.383]    [Pg.494]    [Pg.438]    [Pg.45]    [Pg.62]    [Pg.259]    [Pg.525]    [Pg.47]    [Pg.49]    [Pg.36]   
See also in sourсe #XX -- [ Pg.132 ]

See also in sourсe #XX -- [ Pg.188 ]




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Acid catalysts, heterogeneous

Acid-base bifunctional heterogeneous catalysts

Active heterogeneous catalyst

Alkyne heterogeneous catalyst

Alumina heterogeneous polymerization catalysts

Amorphous, Porous Heterogeneous Catalysts and Supports

Analytical electron microscopy heterogeneous catalyst

Aromatic rings heterogeneous catalysts

Asymmetric Heterogeneous Catalysts Implemented in Industry

Binding and Reactive Sites in Metal Cluster Catalysts Homogeneous-Heterogeneous Bridges

Building Block Approaches to Nanostructured, Single Site, Heterogeneous Catalysts

Carboxylic acids heterogeneous catalysts

Case Heterogenized ILs as Catalysts

Catalyst Concepts in Heterogeneous Catalysis

Catalyst Shapes and Production of Heterogeneous Catalysts

Catalyst copper, heterogeneous

Catalyst heterogeneous catalysts, support

Catalyst heterogeneous oxide

Catalyst heterogenous catalysis

Catalyst surface, accessibility heterogeneity

Catalyst, continued heterogeneous

Catalysts heterogeneity

Catalysts heterogeneity

Catalysts heterogeneous

Catalysts heterogeneous

Catalysts heterogeneous reaction mechanisms

Catalysts heterogeneous reactions

Catalysts heterogenized transition metal

Catalysts heterogenous

Catalysts heterogenous

Catalysts homogeneous versus heterogeneous

Catalysts polymer-immobilized, heterogeneous

Catalysts, heterogeneous/homogeneous

Catalysts, heterogenization

Catalytic converters, heterogeneous catalysts

Catalytic sites heterogeneous catalysts

Characterization of heterogeneous catalysts

Chevrel phases heterogeneous HDS catalysts containing molecular clusters

Chiral heterogeneous catalyst

Chirally Modified Heterogeneous Hydrogenation Catalysts

Chromium catalysts, heterogeneous

Chromocene and Heterogeneous Catalysts

Classes of Heterogeneous Catalysts

Classical heterogeneous catalysts

Clay catalysts heterogeneous composite

Cobalt catalysts, heterogeneous

Conjugated linoleic acids heterogeneous catalysts

Coordination Catalysts 1 Polymerisation with Heterogeneous Ziegler-Natta

Crude Oil to Gasoline and Basic Building Blocks by Heterogeneous Catalysts

Deactivation of Heterogenous Catalysts

Derivation from heterogeneous catalysts

Direct heterogeneous palladium catalyst

Donor heterogeneous catalysts

Enantioselective heterogeneous catalysis catalysts

Enantioselective heterogeneous catalysis enzyme catalysts

Epoxidation heterogeneous catalysts

Ester 123 Heterogeneous catalyst

Esterification of alcohols using heterogeneous acid catalyst

Ethylene with heterogeneous catalysts from

Examples of Heterogeneous Reactions Using Solid Catalysts and Ultrasound

Forms of Heterogeneous Catalysts

Heck heterogeneous catalyst

Heterocycles catalysts: heterogeneous

Heterogeneous Catalysis 4 Nanoparticle-Based Catalysts

Heterogeneous Catalysis Kinetics in Porous Catalyst Particles

Heterogeneous Catalysts Fixed on Ionites

Heterogeneous Catalysts for Clean Technology: Spectroscopy, Design, and Monitoring, First Edition

Heterogeneous Catalysts forms

Heterogeneous Catalysts preparation

Heterogeneous Catalytic Synthesis of ()-Butyl Cinnamate Using a Palladium Nanosphere Catalyst

Heterogeneous Enantioselective Catalysts in Industrial Research and Application

Heterogeneous Fenton-like catalysts

Heterogeneous POM catalysts

Heterogeneous POM-based catalysts

Heterogeneous Polymerization Catalysts Derived from Transition Metal Alkyl Compounds

Heterogeneous Reduction Catalysts

Heterogeneous Sulfide Catalysts

Heterogeneous WGS Catalysts

Heterogeneous acid catalysts Friedel-Crafts acylation

Heterogeneous acid catalysts biodiesel synthesis

Heterogeneous acid-base catalysts

Heterogeneous and Supported Catalysts

Heterogeneous asymmetric catalysis catalyst

Heterogeneous asymmetric catalysis chirally modified catalysts

Heterogeneous asymmetric catalysis inorganic catalysts

Heterogeneous asymmetric catalysis organic catalysts

Heterogeneous asymmetric catalysis solid catalysts

Heterogeneous base catalysts

Heterogeneous basic catalysts

Heterogeneous bulk catalysts

Heterogeneous carbon-supported catalysts

Heterogeneous catalysis active catalysts

Heterogeneous catalysis bifunctional catalysts

Heterogeneous catalysis catalyst

Heterogeneous catalysis catalyst types

Heterogeneous catalysis metallic catalysts

Heterogeneous catalysis mixed catalysts

Heterogeneous catalysis selective catalysts

Heterogeneous catalysis supported metal catalysts

Heterogeneous catalysis zeolite catalysts

Heterogeneous catalysis zeolites as catalysts

Heterogeneous catalyst Bronsted acid sites

Heterogeneous catalyst acetic acid conversion

Heterogeneous catalyst activity

Heterogeneous catalyst alkane isomerization

Heterogeneous catalyst alumina

Heterogeneous catalyst chromia

Heterogeneous catalyst cracking products

Heterogeneous catalyst development pathway

Heterogeneous catalyst effectiveness factor

Heterogeneous catalyst metal catalysts

Heterogeneous catalyst monolithic

Heterogeneous catalyst onto catalysts supports

Heterogeneous catalyst oxide-supported catalysts, organometallic

Heterogeneous catalyst particles

Heterogeneous catalyst particles microscopy

Heterogeneous catalyst particles removal

Heterogeneous catalyst platinum-catalyzed reactions

Heterogeneous catalyst precursors

Heterogeneous catalyst quasi-equilibria

Heterogeneous catalyst rate-limiting step

Heterogeneous catalyst structure

Heterogeneous catalyst support monolithic

Heterogeneous catalyst supported metal catalysts

Heterogeneous catalyst transport effects

Heterogeneous catalyst zeolite-supported catalysts, organometallic

Heterogeneous catalyst zeolites

Heterogeneous catalysts Friedel-Crafts alkylation

Heterogeneous catalysts active components

Heterogeneous catalysts advantages

Heterogeneous catalysts cycloolefins

Heterogeneous catalysts deactivation

Heterogeneous catalysts derived from

Heterogeneous catalysts dispersion

Heterogeneous catalysts features

Heterogeneous catalysts impregnation method

Heterogeneous catalysts industrial applications

Heterogeneous catalysts meaning of term

Heterogeneous catalysts monolayer model

Heterogeneous catalysts overview

Heterogeneous catalysts petrochemical industry

Heterogeneous catalysts polystyrene

Heterogeneous catalysts selective

Heterogeneous catalysts supported

Heterogeneous catalysts supported metal particle preparation

Heterogeneous catalysts synthesis

Heterogeneous catalysts testing

Heterogeneous catalysts types

Heterogeneous catalysts, and

Heterogeneous catalysts, characterization

Heterogeneous catalysts, defined

Heterogeneous catalysts, deposition

Heterogeneous catalysts, sensor materials

Heterogeneous catalysts, site-controlled

Heterogeneous catalysts, site-controlled catalyst chirality

Heterogeneous catalysts, site-controlled stereospecific polymerizations

Heterogeneous catalytic processes catalyst testing

Heterogeneous catalytic reactions bifunctional catalysts

Heterogeneous chemical reactions catalyst effects

Heterogeneous coordination catalyst

Heterogeneous early transition-metal catalyst

Heterogeneous epoxidation on Ti catalysts

Heterogeneous epoxidation on silver catalysts

Heterogeneous epoxidation silver catalyst

Heterogeneous epoxidation titanium catalyst

Heterogeneous heterogenization, chiral catalysts

Heterogeneous hybrid catalyst

Heterogeneous hydrogenation catalysts based on quartz

Heterogeneous immobilization, chiral catalysts

Heterogeneous immobilized catalysts, flow reaction

Heterogeneous metathesis catalysts

Heterogeneous model catalysts

Heterogeneous osmium catalysts

Heterogeneous oxidation catalysts

Heterogeneous polymeric catalysts

Heterogeneous polymerization solid catalysts

Heterogeneous process catalysts effect

Heterogeneous reagent/catalyst immobilization

Heterogeneous ruthenium-based catalyst

Heterogeneous ruthenium-based catalyst systems

Heterogeneous silica-supported catalysts

Heterogeneous solid acid catalysts

Heterogeneous solid catalysts

Heterogeneous supported metal catalyst

Heterogeneous titanium catalyst

Heterogeneous-homogeneous catalytic oxide catalysts

Heterogenization of catalysts

Heterogenization of homogeneous catalysts

Heterogenized homogeneous catalysts

Heterogenized homogenous carbonylation catalysts

Heterogenized metal complex catalyst

Heterogenized transition metal catalysts polymerization with

Heterogenized transition metal catalysts polystyrene

Heterogenizing Homogeneous Catalysts and Their Use in a Continuous Flow Reactor

Homogeneous catalysis heterogeneous catalyst)

Homogeneous catalysts heterogeneous catalyst comparisons

Homogeneous from Heterogeneous Catalysts

Homogeneous, heterogeneous catalysts, bridging

Hybrid-phase catalysts heterogeneous

Hydration and Dehydration by Heterogeneous Catalysts

Hydrogenation Using Heterogeneous Catalysts

Hydrogenation catalysts: heterogeneous

Hydrogenation with heterogeneous catalysts

Industrial processes heterogeneous catalysts used

Iron catalysts, heterogeneous

Iron-ammonia catalysts surface heterogeneity

Linear heterogeneous catalysts

Liquid-phase Oxidation over Heterogeneous Catalysts

Metal Coordination Sites in Heterogeneous Catalysts

Metal as heterogeneous catalysts

Metal catalysts heterogeneous

Metal fluorides, heterogeneous catalysts

Metal oxides, as heterogenous catalysts

Metallocene catalysts heterogeneous

Metals, as heterogenous catalysts

Molecular Weight Distribution of SPS with Heterogeneous Catalysts

Molecular weight distribution with heterogeneous catalysts

Molybdenum catalysts, heterogeneous

Multimetallic heterogeneous catalyst

Nanocluster heterogeneous catalysts

Non-crystalline heterogeneous catalysts

Novel Colloid Based Heterogeneous Catalysts

Novel Heterogenized Catalysts for Asymmetric Ring-Opening Reactions of Epoxides

Olefin heterogeneous catalysts

Olefins heterogeneous polymerization catalysts

Organometallic clusters heterogeneous catalysts

Oxide catalyst chemical heterogeneity

Oxygen heterogeneous catalysts

Palladium heterogeneous catalysts

Particle sites, heterogeneous catalysts

Physical Fabrication of Nanostructured Heterogeneous Catalysts

Platinum catalysts, heterogeneous

Polymer heterogeneous catalysts

Polymer supported metal catalysts heterogenous catalyst

Polymerisation reactions heterogeneous catalysts

Polymerization heterogeneous catalysts

Preparation advances homogeneous, heterogeneous catalysts

Preparation of Heterogeneous Catalysts for Chemo- and Enantioselective Hydrogenation Reactions

Preparation of heterogeneous catalysts

Preparation of the heterogeneous catalyst nickel-on-charcoal

Process Development Critical Factors for the Application of (Heterogeneous) Enantioselective Catalysts

Production and Characterization of Heterogeneous Catalysts

Reactions heterogeneous hydrogenation catalyst

Reactive heterogeneous catalyst

Ruthenium catalysts, heterogeneous

Selective heterogeneous catalysts Friedel-Crafts alkylation

Selective heterogeneous catalysts advantages

Selective heterogeneous catalysts features

Selective heterogeneous catalysts hydrophilicity-hydrophobicity

Silica heterogeneous polymerization catalysts from

Silica/titania heterogeneous catalyst

Site-Isolated Heterogeneous Catalysts

Solid catalysts zeolite heterogeneous catalysis

Solid support catalysts heterogeneous hydrogenation

Solids as Heterogeneous Catalysts

Sonogashira heterogeneous catalyst development

Sonogashira reaction heterogeneous catalysts

Stereospecific polymerizations heterogeneous catalysts

Styrene heterogeneous catalysts

Superbasic Heterogeneous Catalysts

Supported Heterogeneous Catalyst Systems

Surface sites, heterogeneous catalysts

Synthesis of heterogeneous catalysts

Tailoring Heterogeneous Catalysts

Thallium-based heterogeneous catalysts

The Heterogeneity of Catalyst Surfaces for Chemisorption Hugh S. Taylor

The Oligomerization of Alkenes by Heterogeneous Catalysts

The Structure of Heterogeneous Catalysts

The active phases in heterogeneous HDS catalysts

Transfer Hydrogenation Using Heterogeneous Catalysts

Transition metal alkyl compounds heterogeneous polymerization catalysts

Transition metal heterogeneous polymerization catalysts

Triazoles heterogeneous copper catalysts

Tungstate catalysts, heterogenization

Tungsten catalysts, heterogeneous

Type I Homochiral MOCP Catalysts in Heterogeneous Asymmetric Reactions

Type II Homochiral MOCP Catalysts in Heterogeneous Asymmetric Reactions

Water heterogeneous catalysts

Ways of Using Heterogeneous Catalysts

What Heterogeneous Catalysts are Active in Formation of Oxygenated Products

Zeolite catalysts heterogeneous composite

Ziegler-Natta catalysts heterogeneous

Ziegler-Natta catalysts heterogeneous systems

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