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Catalyst production

The representation of a chemical reaction should include the connection table of all participating species starting materials, reagents, solvents, catalysts, products) as well as Information on reaction conditions (temperature, concentration, time, etc.) and observations (yield, reaction rates, heat of reaction, etc.). However, reactions are only Insuffclently represented by the structure of their starting materials and products,... [Pg.199]

G74C D-0379 Catalysts, product buUetin, United Catalysts Inc., LouisviUe, Ky. [Pg.463]

Figure 8 shows the characteristic sawtooth temperature profile which represents the thermodynamic inefficiency of this reactor type as deviations from the maximum reaction rate. Catalyst productivity is further reduced because not all of the feed gas passes through all of the catalyst. However, the quench converter has remained the predominant reactor type with a proven record of reflabiUty. [Pg.279]

Adl b tic Converters. The adiabatic converter system employs heat exchangers rather than quench gas for interbed cooling (Fig. 7b). Because the beds are adiabatic, the temperature profile stiU exhibits the same sawtooth approach to the maximum reaction rate, but catalyst productivity is somewhat improved because all of the gas passes through the entire catalyst volume. Costs for vessels and exchangers are generally higher than for quench converter systems. [Pg.279]

LLDPE by itself does not present any health-related hazard on account of its chemical inertness and low toxicity. Consequently, film, containers, and container Hds made from LLDPE are used on a large scale in food and dmg packaging. Some LLDPE grades produced with unsupported metallocene catalysts have an especially high purity due to high catalyst productivity and a low contamination level of resins with catalyst residue. FDA approved the use of film manufactured from these resins for food contact and for various medical appHcations (80). However, if LLDPE articles contain fillers, processing aids, or colorants, thek health factors must then be judged separately. [Pg.404]

Reaction between butadiene and CO2 has been extensively studied (171) since the reaction was first demonstrated (167—170). This reaction has been shown to be catalyzed by Pd (172,173), Ni (174), Ru (175), Pt (178), and Rh (172,173) catalysts. Products include gamma (5) and delta lactones (6), acids (7,8), and esters (9). Mechanistic studies have shown that butadiene initially forms a dimer (Pd, Ru, Ni) or trimer (Rh) intermediate followed by CO2 insertion (171). The fate of these intermediates depends on the metal, the ligands, and the reaction conditions. [Pg.345]

Catalysts. Historically, cmde clays have been used to some extent in petroleum refining (20). More recently, however, processed clays are increasingly used as raw materials and converted to more reactive catalyst products. Various proprietary processes are used and numerous patents have been issued. [Pg.210]

Ethyl aluminum dichloride (EADC) is used in the rnanufacmre of certain catalysts for making LDPE. Occasionally, the batch operation involving the catalyst production results in an off-spec lot. This off-spec lot is washed from the reactor (impregantor) with water and hexane, and must be sent to a waste disposal facility. The facility treats this waste in a hydrolysis reaction (i.e., with water and mild agitation). If the reaction is exothermic, what are the potential air pollution and fire problems associated with the waste treatment ... [Pg.187]

So far only two groups have reported details of the use of ionic liquids with wholecell systems (Entries 3 and 4) [31, 32]. In both cases, [BMIM][PF(3] was used in a two-phase system as substrate reservoir and/or for in situ removal of the product formed, thereby increasing the catalyst productivity. Scheme 8.3-1 shows the reduction of ketones with bakers yeast in the [BMIM][PF(3]/water system. [Pg.339]

Enzyme Form Proteins are practically insoluble in most organic solvents therefore, in the absence of any special treatment, they are usually present as a solid suspension. This simplifies catalyst-product separation and enzyme reutilization. [Pg.9]

Firstly, there are technical reasons concerning catalyst and reactor requirements. In the chemical industry, catalyst performance is critical. Compared to conventional catalysts, they are relatively expensive and catalyst production and standardization lag behind. In practice, a robust, proven catalyst is needed. For a specific application, an extended catalyst and washcoat development program is unavoidable, and in particular, for the fine chemistry in-house development is a burden. For coated systems, catalyst loading is low, making them unsuited for reactions occurring in the kinetic regime, which is particularly important for bulk chemistry and refineries. In that case, incorporated monolithic catalysts are the logical choice. Catalyst stability is crucial. It determines the amount of catalyst required for a batch process, the number of times the catalyst can be reused, and for a continuous process, the run time. [Pg.203]

Catalyst Product distrihution (mol %) Methane Ethene Ethane Propene Propane Butene Butane i-Butene... [Pg.319]

In addition, also nonheme iron catalysts containing BPMEN 1 and TPA 2 as ligands are known to activate hydrogen peroxide for the epoxidation of olefins (Scheme 1) [20-26]. More recently, especially Que and coworkers were able to improve the catalyst productivity to nearly quantitative conversion of the alkene by using an acetonitrile/acetic acid solution [27-29]. The carboxylic acid is required to increase the efficiency of the reaction and the epoxide/diol product ratio. The competitive dihydroxylation reaction suggested the participation of different active species in these oxidations (Scheme 2). [Pg.85]

Catalyst Production. Supported magnetite particles were produced on Grafoll (Union Carbide), a high surface area form of graphite. The nature of Grafoll and the reasons It is convenient to use In MCssbauer spectroscopy experiments eu e described elsewhere (25). Grafoll is also well suited for magnetic susceptibility experiments. [Pg.522]

A major difference in the evaluation of the two approaches concerns catalyst synthesis. Whereas catalyst production is integrated in the biocatalytic procedure (Scheme 5.4) and thus also contained in the cost index and the environmental factor, it is not considered in the chemical catalytic approach. A more realistic approach is to include the synthesis of the Jacobsen catalyst (Scheme 5.5) in the mass balance. In Figure 5.8, resources used for catalyst production are separately indicated ( Further Syntheses ). For the biocatalytic procedure, water dominates the environmental factor. The environmental factor increases for the chemical procedure, whereas the cost index, when representing only the raw material costs, declines if the (salen)Mn-catalyst is assumed to be synthesized and not bought. [Pg.212]

In homogeneous catalysis often precious metals are used, while the ligands are also expensive. Therefore, the catalyst productivity indeed should be high, and catalyst losses should be minimized, requiring nearly complete recovery of the metal, and the ligands. [Pg.110]

The BET surface area of the catalysts is summarised in Table 3. The enhancement could be explained in case of MO-s with the reconstruction of the lamella structure. The reason of enhancement in the presence of 212 is still not known. All the other cases significant decrease can be observed. The surface area of metallic part of the used RNi-s shows increase from A to C, with the increasing temperature of the catalyst production, indicating growing Ni distribution. [Pg.440]

The objective of this chapter is to detail considerations that must be addressed in order to successfully marry a catalyst technology with catalyst/product separation technology. The focus of this chapter is hydroformylation, but the general principles should apply to many homogeneous precious-metal catalyzed processes. [Pg.10]

Selectivity refers to the fraction of raw material alkene that is converted to product aldehyde, but since hydroformylation typically gives both a linear and branched isomer, selectivity also refers to the relative amounts of each. The linear branched (l b) ratio is highly catalyst dependant. One must simultaneously consider whether the proposed catalyst will give the desired l b selectivity and also whether the proposed catalyst is feasible for use with the catalyst/product separation technologies. For example, water extraction of a polar product, such as in the hydroformylation of allyl alcohol to give 4-hydroxybutanal, would not work well with a sodium salt of a sulfonated phosphine since both are water soluble. [Pg.19]


See other pages where Catalyst production is mentioned: [Pg.522]    [Pg.42]    [Pg.160]    [Pg.458]    [Pg.458]    [Pg.455]    [Pg.264]    [Pg.168]    [Pg.228]    [Pg.115]    [Pg.48]    [Pg.99]    [Pg.554]    [Pg.363]    [Pg.203]    [Pg.222]    [Pg.257]    [Pg.60]    [Pg.69]    [Pg.386]    [Pg.106]    [Pg.5]    [Pg.186]    [Pg.187]    [Pg.167]    [Pg.184]    [Pg.145]    [Pg.123]    [Pg.10]    [Pg.17]    [Pg.20]    [Pg.64]   
See also in sourсe #XX -- [ Pg.35 , Pg.102 , Pg.103 , Pg.104 , Pg.105 ]

See also in sourсe #XX -- [ Pg.474 ]

See also in sourсe #XX -- [ Pg.409 ]




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A Posteriori Separation of Products and Catalysts

Acetic acid, production catalyst

Acetic anhydride, production catalyst

Acid catalysts for biodiesel production

Ammonia production catalysts used

Anthraquinone as a catalyst in the production of hydrogen peroxide

Bio)catalyst Productivity

Biodiesel production solid acid catalysts

Biodiesel production solid base catalysts

Case - Use of Carbon Nanotube-Based Catalysts in Hydrogen Production

Catalysis/catalysts fuel production

Catalyst (modeling/simulation product

Catalyst Production and Operation

Catalyst Shapes and Production of Heterogeneous Catalysts

Catalyst breakdown products

Catalyst current production processes

Catalyst deactivation product

Catalyst dependence isomerization products

Catalyst particle size density production

Catalyst poisoning hydrogen production

Catalyst productivity

Catalyst productivity

Catalyst, alumina hydrogenation, Universal Oil Products

Catalysts acrylonitrile production

Catalysts effects on yields and product properties

Catalysts ethylbenzene production

Catalysts for biodiesel production

Catalysts process engineering/product recover

Catalysts product inhibition

Catalysts product selectivities over

Catalysts silica alumina production

Catalysts styrene production

Catalytic Performances of Perovskite-Type Catalysts for H2 Production from Alcohols

Clay minerals catalysts, hydrogen production from water

Cobalt catalyst products from

Cobalt catalysts reaction products

Cobalt catalysts, product distribution

Complex product catalyst

Copper Catalyst Production

Crystalline iron catalyst, product

Direct catalyst productivity

Formaldehyde, production catalyst

HZSM-5 zeolite catalysts product distribution

Heterogeneous catalyst cracking products

Hydrogen production catalyst

Hydrogenation catalysts food production

Iodide catalyst acetic acid production

Iodide catalyst acetic anhydride production

Ionic Liquids, Catalyst Recycle, Selectivity, and Product Separation

Iridium catalyst, acetic acid production

Iron catalysts reaction products

Liquid products yields with various catalysts

Manganese oxide catalysts, oxygen production from water

Metallocene catalysts copolymer production

Metathesis in Natural Product Synthesis: Strategies, Substrates and Catalysts. Edited by Janine Cossy

Methanol synthesis catalyst production

Methanol, production catalyst

Methanol, production catalyst poisoning

Molecular Catalysts for H2 Conversion and Production

Multisite catalysts production

Nanotechnology products catalysts

Nickel catalysts, Raney Universal Oil Products

Nickel-activated carbon catalysts products

Novolac production, acidic catalysts

Petrochemical catalysts ethylene production

Phthalocyanines catalysts, oxygen production from water

Platinum oxides catalysts, oxygen production from water

Porphyrins catalysts, oxygen production from water

Product Separation and Catalyst Recycling

Product continuous catalyst regeneration

Product separation catalysts

Production and Characterization of Heterogeneous Catalysts

Production and Physical Characteristics of Solid Catalysts

Production processes catalysts

Production strategies using catalysts

Production using small amounts strong catalysts

Productivity of catalysts

Relationships between Catalyst Production and Performance

Rhodium catalyst acetic acid production

Rhodium catalyst acetic anhydride production

Rhodium-ruthenium catalysts product selectivity

Ruthenium catalysts acid production

Ruthenium catalysts, product selectivities

Ruthenium complex catalysts product distribution

Ruthenium oxide catalysts, oxygen production from water

Ruthenium-cobalt catalysts, iodide production

SYNTHETIC NITROGEN PRODUCTS Catalyst

Silver catalysts natural product synthesis

Sulphuric acid catalyst production

Titanium oxide catalysts, hydrogen production from water

Titanium-Based Ziegler Catalysts for the Production of Polyethylene

Transition metal catalysts natural products synthesis

Transition metal catalysts pharmaceutical products

What Heterogeneous Catalysts are Active in Formation of Oxygenated Products

Zeolites catalysts, hydrogen production from water

Ziegler-Natta catalysts polyethylene production

Ziegler-Natta catalysts polypropylene production

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