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Catalytic reactors reaction

Some Examples of Industrially Important Catalytic Reactions/Reactors... [Pg.754]

Fig. 8.3 Computed characteristic catalytic chemical time scales of gas-phase reacting species in a batch reactor, when considering only catalytic reactions. Reactor conditions p = 1 bar, cp = 0.4, S/... Fig. 8.3 Computed characteristic catalytic chemical time scales of gas-phase reacting species in a batch reactor, when considering only catalytic reactions. Reactor conditions p = 1 bar, cp = 0.4, S/...
However, before extrapolating the arguments from the gross patterns through the reactor for homogeneous reactions to solid-catalyzed reactions, it must be recognized that in catalytic reactions the fluid in the interior of catalyst pellets may diSer from the main body of fluid. The local inhomogeneities caused by lowered reactant concentration within the catalyst pellets result in a product distribution different from that which would otherwise be observed. [Pg.48]

Fluidized bed noncatalytic reactors. Fluidized heds are also suited to gas-solid noncatalytic reactions. All the advantages described earlier for gas-solid catalytic reactions apply. As an example. [Pg.59]

The implementation of high-pressure reaction cells in conjunction with UFIV surface science techniques allowed the first tme in situ postmortem studies of a heterogeneous catalytic reaction. These cells penult exposure of a sample to ambient pressures without any significant contamination of the UFIV enviromnent. The first such cell was internal to the main vacuum chamber and consisted of a metal bellows attached to a reactor cup [34]- The cup could be translated using a hydraulic piston to envelop the sample, sealing it from... [Pg.938]

Process. As soHd acid catalysts have replaced Hquid acid catalysts, they have typically been placed in conventional fixed-bed reactors. An extension of fixed-bed reactor technology is the concept of catalytic distillation being offered by CR L (48). In catalytic distillation, the catalytic reaction and separation of products occur in the same vessel. The concept has been appHed commercially for the production of MTBE and is also being offered for the production of ethylbenzene and cumene. [Pg.53]

Tubular Reactors. The tubular reactor is exceUent for obtaining data for fast thermal or catalytic reactions, especiaHy for gaseous feeds. With sufficient volume or catalyst, high conversions, as would take place in a large-scale unit, are obtained conversion represents the integral value of reaction over the length of the tube. Short tubes or pancake-shaped beds are used as differential reactors to obtain instantaneous reaction rates, which can be computed directly because composition changes can be treated as differential amounts. Initial reaction rates are obtained with a fresh feed. Reaction rates at... [Pg.515]

Work in the area of simultaneous heat and mass transfer has centered on the solution of equations such as 1—18 for cases where the stmcture and properties of a soHd phase must also be considered, as in drying (qv) or adsorption (qv), or where a chemical reaction takes place. Drying simulation (45—47) and drying of foods (48,49) have been particularly active subjects. In the adsorption area the separation of multicomponent fluid mixtures is influenced by comparative rates of diffusion and by interface temperatures (50,51). In the area of reactor studies there has been much interest in monolithic and honeycomb catalytic reactions (52,53) (see Exhaust control, industrial). Eor these kinds of appHcations psychrometric charts for systems other than air—water would be useful. The constmction of such has been considered (54). [Pg.106]

The main by-products ia the dehydrogenation reactor are toluene and benzene. The formation of toluene accounts for the biggest yield loss, ie, approximately 2% of the styrene produced when a high selectivity catalyst is used. Toluene is formed mostly from styrene by catalytic reactions such as the foUowiag ... [Pg.481]

Direct Chlorination of Ethylene. Direct chlorination of ethylene is generally conducted in Hquid EDC in a bubble column reactor. Ethylene and chlorine dissolve in the Hquid phase and combine in a homogeneous catalytic reaction to form EDC. Under typical process conditions, the reaction rate is controlled by mass transfer, with absorption of ethylene as the limiting factor (77). Ferric chloride is a highly selective and efficient catalyst for this reaction, and is widely used commercially (78). Ferric chloride and sodium chloride [7647-14-5] mixtures have also been utilized for the catalyst (79), as have tetrachloroferrate compounds, eg, ammonium tetrachloroferrate [24411-12-9] NH FeCl (80). The reaction most likely proceeds through an electrophilic addition mechanism, in which the catalyst first polarizes chlorine, as shown in equation 5. The polarized chlorine molecule then acts as an electrophilic reagent to attack the double bond of ethylene, thereby faciHtating chlorine addition (eq. 6) ... [Pg.417]

Exothermicity. The catalytic reactions are often exothermic bond-forming reactions of small molecules that give larger molecules. Consequendy, the reactors are designed for efficient heat removal. They may be jacketed or contain coils for heat-transfer media, or the heat of reaction may be used to vaporize the products and aid in the downstream separation by distillation. [Pg.161]

Catalytic A catalytic-membrane reactor is a combination heterogeneous catalyst and permselective membrane that promotes a reaction, allowing one component to permeate. Many of the reactions studied involve H9. Membranes are metal (Pd, Ag), nonporous metal oxides, and porous structures of ceran iic and glass. Falconer, Noble, and Speriy [in Noble and Stern (eds.), op. cit., pp. 669-709] review status and potential developments. [Pg.2050]

Catalytic Membrane Reactors Membrane reactors combine reaction and separation in a single vessel. By removing one of the... [Pg.2098]

The most common heterogeneous catalytic reaction is hydrogenation. Most laboratory hydrogenations are done on liquid or solid substrates and usually in solution with a slurried catalyst. Therefore the most common batch reactor is a stirred vessel, usually a stirred autoclave (see Figure 2.1.1 for a typical example). In this system a gaseous compound, like hydrogen, must react at elevated pressure to accelerate the process. [Pg.30]

Various experimental methods to evaluate the kinetics of flow processes existed even in the last centuty. They developed gradually with the expansion of the petrochemical industry. In the 1940s, conversion versus residence time measurement in tubular reactors was the basic tool for rate evaluations. In the 1950s, differential reactor experiments became popular. Only in the 1960s did the use of Continuous-flow Stirred Tank Reactors (CSTRs) start to spread for kinetic studies. A large variety of CSTRs was used to study heterogeneous (contact) catalytic reactions. These included spinning basket CSTRs as well as many kinds of fixed bed reactors with external or internal recycle pumps (Jankowski 1978, Berty 1984.)... [Pg.53]

For catalytic reactions in an open system, V reactor volume contains the catalyst and concentrations arc referred per unit of flowing volume, m /s. [Pg.252]

Heterogeneous catalytic systems offer the advantage that separation of the products from the catalyst is usually not a problem. The reacting fluid passes through a catalyst-filled reactor m the steady state, and the reaction products can be separated by standard methods. A recent innovation called catalytic distillation combines both the catalytic reaction and the separation process in the same vessel. This combination decreases the number of unit operations involved in a chemical process and has been used to make gasoline additives such as MTBE (methyl tertiai-y butyl ether). [Pg.226]

Catalyst and products are quickly separated in the reactor. However, some thermal and non-selective catalytic reactions continue. A number... [Pg.8]

The kinetics of a complex catalytic reaction can be derived from the results obtained by a separate study of single reactions. This is important in modeling the course of a catalytic process starting from laboratory data and in obtaining parameters for catalytic reactor design. The method of isolation of reactions renders it possible to discover also some other reaction paths which were not originally considered in the reaction network. [Pg.48]

Suppose a gradientless reactor is used to obtain intrinsic rate data for a catalytic reaction. Gas-phase concentrations are measured, and the data are fit to a rate expression using the methods of Chapter 7. The rate expression can be arbitrary ... [Pg.355]

Dudukovic, M. P., Trends in catalytic reaction engineering, Catal. Today, 48, 5-15 (1999). A comprehensive review of the complex hydrodynamic issues associated with three-phase reactors is given in... [Pg.432]


See other pages where Catalytic reactors reaction is mentioned: [Pg.952]    [Pg.952]    [Pg.2709]    [Pg.519]    [Pg.482]    [Pg.688]    [Pg.733]    [Pg.143]    [Pg.128]    [Pg.174]    [Pg.262]    [Pg.93]    [Pg.463]    [Pg.270]    [Pg.288]    [Pg.96]    [Pg.226]    [Pg.416]    [Pg.84]    [Pg.87]    [Pg.417]    [Pg.156]    [Pg.203]    [Pg.251]    [Pg.254]    [Pg.66]    [Pg.66]    [Pg.69]   
See also in sourсe #XX -- [ Pg.108 ]




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Catalytic reactions and reactors

Catalytic reactions in a membrane reactor configuration

Catalytic reactor

FIXED-BED CATALYTIC REACTORS FOR FLUID-SOLID REACTIONS

Flow reactors for testing gas-solid catalytic reactions

Fluidized Bed Catalytic Reactor with Consecutive Reactions

Integral reactor, catalytic reaction

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Reaction kinetics, plant-scale catalytic reactor

Reaction system catalytic reactor

Reactive Stripping in Structured Catalytic Reactors Hydrodynamics and Reaction Performance

Reactor Design for Heterogeneous Catalytic Reactions

Reactors for Catalytic Gas-Phase Reactions

Reactors reaction

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Simulation 3 Reactor Modeling for a Homogeneous Catalytic Reaction

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