WO2013135666A1 - Réacteur à écoulement axial à base d'un alliage fe-cr-al - Google Patents

Réacteur à écoulement axial à base d'un alliage fe-cr-al Download PDF

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Publication number
WO2013135666A1
WO2013135666A1 PCT/EP2013/054957 EP2013054957W WO2013135666A1 WO 2013135666 A1 WO2013135666 A1 WO 2013135666A1 EP 2013054957 W EP2013054957 W EP 2013054957W WO 2013135666 A1 WO2013135666 A1 WO 2013135666A1
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flow reactor
fluid
heating
group
catalyst
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PCT/EP2013/054957
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German (de)
English (en)
Inventor
Alexander Karpenko
Vanessa GEPERT
Emanuel Kockrick
Leslaw Mleczko
Albert TULKE
Daniel Gordon Duff
Daniel Wichmann
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Bayer Intellectual Property Gmbh
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Publication of WO2013135666A1 publication Critical patent/WO2013135666A1/fr

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
    • B01J8/008—Details of the reactor or of the particulate material; Processes to increase or to retard the rate of reaction
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J12/00—Chemical processes in general for reacting gaseous media with gaseous media; Apparatus specially adapted therefor
    • B01J12/007—Chemical processes in general for reacting gaseous media with gaseous media; Apparatus specially adapted therefor in the presence of catalytically active bodies, e.g. porous plates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J19/02—Apparatus characterised by being constructed of material selected for its chemically-resistant properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J19/24—Stationary reactors without moving elements inside
    • B01J19/248—Reactors comprising multiple separated flow channels
    • B01J19/2485—Monolithic reactors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/002—Mixed oxides other than spinels, e.g. perovskite
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
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    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/16—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
    • B01J23/32—Manganese, technetium or rhenium
    • B01J23/36—Rhenium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
    • B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/56—Platinum group metals
    • B01J23/63—Platinum group metals with rare earths or actinides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/89—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals
    • B01J23/892—Nickel and noble metals
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/50—Catalysts, in general, characterised by their form or physical properties characterised by their shape or configuration
    • B01J35/56—Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional monoliths
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
    • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
    • B01J8/04—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds
    • B01J8/0446—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds the flow within the beds being predominantly vertical
    • B01J8/0449—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds the flow within the beds being predominantly vertical in two or more cylindrical beds
    • B01J8/0453—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds the flow within the beds being predominantly vertical in two or more cylindrical beds the beds being superimposed one above the other
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
    • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
    • B01J8/04—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds
    • B01J8/0496—Heating or cooling the reactor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
    • B01J2208/00008—Controlling the process
    • B01J2208/00017—Controlling the temperature
    • B01J2208/00389—Controlling the temperature using electric heating or cooling elements
    • B01J2208/00398—Controlling the temperature using electric heating or cooling elements inside the reactor bed
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
    • B01J2208/00008—Controlling the process
    • B01J2208/00017—Controlling the temperature
    • B01J2208/00389—Controlling the temperature using electric heating or cooling elements
    • B01J2208/00415—Controlling the temperature using electric heating or cooling elements electric resistance heaters
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
    • B01J2208/00008—Controlling the process
    • B01J2208/00017—Controlling the temperature
    • B01J2208/00522—Controlling the temperature using inert heat absorbing solids outside the bed
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/02—Apparatus characterised by their chemically-resistant properties
    • B01J2219/0204—Apparatus characterised by their chemically-resistant properties comprising coatings on the surfaces in direct contact with the reactive components
    • B01J2219/0236—Metal based
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/02—Apparatus characterised by their chemically-resistant properties
    • B01J2219/025—Apparatus characterised by their chemically-resistant properties characterised by the construction materials of the reactor vessel proper
    • B01J2219/0277—Metal based
    • B01J2219/0286—Steel
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/24—Stationary reactors without moving elements inside
    • B01J2219/2401—Reactors comprising multiple separate flow channels
    • B01J2219/2402—Monolithic-type reactors
    • B01J2219/2409—Heat exchange aspects
    • B01J2219/2416—Additional heat exchange means, e.g. electric resistance heater, coils
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/24—Stationary reactors without moving elements inside
    • B01J2219/2401—Reactors comprising multiple separate flow channels
    • B01J2219/2402—Monolithic-type reactors
    • B01J2219/2425—Construction materials
    • B01J2219/2427—Catalysts
    • B01J2219/2428—Catalysts coated on the surface of the monolith channels
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/24—Stationary reactors without moving elements inside
    • B01J2219/2401—Reactors comprising multiple separate flow channels
    • B01J2219/2402—Monolithic-type reactors
    • B01J2219/2425—Construction materials
    • B01J2219/2427—Catalysts
    • B01J2219/243—Catalyst in granular form in the channels
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/74—Iron group metals
    • B01J23/75—Cobalt

Definitions

  • the present invention relates to a flow reactor for reacting a fluid comprising reactants, comprising in the flow direction of the fluid a plurality of heating levels, which are electrically heated by heating elements and wherein the heating levels are flowed through by the fluid, wherein at least one heating element, a catalyst is arranged and there is heated. It further relates to a method for operating a flow reactor according to the invention.
  • Ferritic iron-chromium-aluminum alloys are preferably used in the prior art as a material for heating conductors in oxidative atmospheres (Werner Schatt, Klaus-Peter Wieters, Bernd Kieback (ed.); Powder metallurgy, technologies and materials; Springer-Verlag; Edition 2006; ISBN 354023652X, 9783540236528; page 167).
  • EP 0 802 373 A2 iron-chromium-aluminum alloys are used as material for ground electrodes of pilot burners.
  • EP 2 3 5 1 860 AI describes a biocompatible material of a stainless, alloyed stainless steel and at least one martensitic boundary layer formed by a heat treatment under nitriding and subsequent cooling, characterized in that orthogonal to the surface inside the sample, the martensitic surface layer exhibits a nearly linear course of the accompanying hardening and Stainless steel is nickel free.
  • the steel material is selected from the steel groups with the material numbers 1.40xx, 1.41xx, 1.45xx, 1.46xx and 1.47xx.
  • WO 2006/036193 discloses a microchannel reactor with a microreaction channel.
  • This microchannel comprises a metal substrate, a dense and substantially defect-free aluminum oxide layer on the metal substrate and catalyst metal particles on the aluminum oxide layer.
  • the earlier patent application WO 2005/094983 A2 describes a microchannel reactor and catalysts which contain a layer of a metal-alumide or which are prepared in a process in which a metal-alumide layer is formed as an intermediate.
  • Non-directly heated, wash-coated Fe-Cr-Alloy carrier bodies are used, for example, for the reactions of methane steam reforming at up to 950 ° C. (Albertazzi et al., 2010, in: Handbook of Environmental Research, Editors: A. Edelstein, D. Baer , pp. 541-550, Nova Science Publishers, Inc.) and others for CO oxidation, namely auto exhaust catalysis (Wu et al., Surface & Coatings Technology 190 (2005) 434-439).
  • the object of the present invention is therefore to provide a reactor suitable for this purpose.
  • a flow reactor for the reaction of a fluid comprising reactants comprising in the flow direction of the fluid a plurality of heating levels, which are electrically heated by heating elements and wherein the Fleizebenen are flowed through by the fluid, wherein arranged on at least one Fleizelement a catalyst is and is heated there and wherein at least a portion of the fluid contacting inner surface of the flow reactor is set up and provided to reach a temperature of> 600 ° C during operation of the flow reactor.
  • the flow reactor is characterized in that> 90% of the material of this designed and provided inner surface of the flow reactor comprises an Fe-Cr-Al alloy.
  • Another object of the present invention is a method for operating a flow reactor, comprising the steps of a) providing an aforementioned flow reactor according to the invention; b) electrically heating at least one of the heating elements of the aforementioned flow reactor according to the invention; and c) passing a fluid comprising reactant through the aforementioned flow reactor according to the invention with at least partial reaction of the reactants of the fluid.
  • Reactions that can be carried out in the flow reactor according to the invention are, for example, the dry reforming of methane (DR, CH4 + CO2 * 2 CO + 2 H2), the reverse Water gas shift reaction (RWGS, C0 2 + H 2 ⁇ CO + H 2 0), the partial oxidation of methane
  • the Fe-Cr-Ai alloys according to the invention build a layer of aluminum oxide at the surface in a pretreatment at temperatures above 100 ° C and presence of, for example, atmospheric oxygen within a few hours.
  • This layer preferably constitutes an intrinsic constituent of the catalyst (for example the carrier for the active particles or for further catalyst or support layers).
  • the layer is formed in situ from the material, this has the advantage, inter alia, that a regeneration of the Alummiumoxidschutz für can be carried out under oxidative conditions at suitable temperatures. Furthermore, this results in the fact that the layer can be produced during calcination under suitable conditions on geometrically demanding components.
  • the layer is very uniform and homogeneous, thereby a uniform, heat transfer to the catalyst allows and achieves a particularly good efficiency in one of the electric heating.
  • the uniformity of the layer also causes an improved adhesion and thermal shock resistance of applied noble metal or transition metal-containing nanoparticles or powdered catalysts.
  • the homogeneous layer of aluminum oxide has no or only very small amounts of nickel and iron, which can be removed by carbonyl formation before the reactor and then decompose and deposit in the hot region such as in the reactor, ie in the catalyst zone. In this way, the catalyst activity would be reduced or the deposits of iron and nickel can act as catalyst poisons.
  • the aluminum oxide layer has a particularly high affinity for aluminum-based Katalysatorbeschichlonne.
  • the Fe-Cr-Al alloys are ferritic alloys. According to the invention, it is provided that> 90% of the material of the inner surface of the flow reactor which is set up and provided for a temperature of> 600 ° C. during operation of the reactor comprises an Fe-Cr-Al alloy.
  • this inner surface is> 95% and more preferably> 98%.
  • loose bulkings of moldings or monolithic ceramic moldings not.
  • pressure-bearing steel shell constructions which are separated by insulating layers from the hot reaction fluid.
  • the "hot” parts of the reactor have the Fe-Cr-Al alloy (to prevent soot formation) and the "cold” parts be made of other materials such as carbon steel or 1.4571 (V4A).
  • "cold" parts of the Fe-Cr-Al alloy reactor may also be constructed.
  • FIG. 1 -4 schematic flow reactors in expanded representation
  • the Fe-Cr-Al alloy has the composition of> 20% by weight to ⁇ 30% by weight Cr,> 4% by weight to ⁇ 7.5% by weight of Al and Residual Fe and unavoidable impurities.
  • a preferred composition is> 21% by weight to ⁇ 23% by weight Cr,> 5% by weight to ⁇ 6% by weight Al and the remainder being Fe and unavoidable impurities.
  • ferritic Fe-Cr-Al alloys such as the type with the material number 1 .4765 (Kanthai® AI).
  • the flow reactor comprises feed lines and / or leads, in which the material of> 90% of its inner surface comprises an Fe-Cr-Al alloy.
  • the layer of alumina formed herein acts as a protection against high temperature corrosion by the mechanism of metal dusting and their types of corrosion. In addition, the tendency for unwanted side reaction on the walls, such as soot deposition, is reduced.
  • At least a portion of the catalyst is disposed on an inner surface of the flow reactor comprising Fe-Cr-Al alloy.
  • FeCrAl heaters it is possible to utilize the ac tivity that forms the M aterial thermal action in the presence of air / oxygen to form an AkCb protective layer.
  • This passivation layer can serve as the basis of a washcoat which acts as a catalytically active coating.
  • an intermediate level between two heating levels is arranged at least once, wherein the intermediate level can also be traversed by the fluid.
  • the intermediate level or its contents can also be catalytically coated. This not only serves as a contact surface for the metallic conductor, but also generates a pressure loss depending on the porosity and thickness, which results in better flow distribution, especially in the reactor.
  • the combination of Schuieiter and intermediate level (or support surface) can then lie on a metallic support structure, which ensures the mechanical stability. It is preferred that the intermediate plane is an electrical insulation, in particular in the presence of a metallic support structure.
  • a dwell of a reacting fluid can continue to be achieved, within which there is a more favorable heat distribution.
  • the reaction can be influenced in a comparatively simple manner. Furthermore, it is possible to influence the reaction by catalytic coatings in different types or amounts in the intermediate level or their content.
  • FIG. 1 schematically shown flow reactor is flowed through by a reactant fluid from top to bottom, as shown by the arrows in the drawing.
  • the fluid may be liquid or gaseous and may be single-phase or multi-phase.
  • the fluid is gaseous. It is conceivable that the fluid contains only reactants and reaction products, but also that additionally inert components such as inert gases are present in the fluid.
  • the reactor has a plurality of (four in the present case) heating levels 100, 101, 102, 103, which are electrically heated by means of corresponding fuel elements 110, 111, 112, 113.
  • the heating levels 100, 101, 102, 103 are flowed through by the fluid during operation of the reactor, and the heating elements 110, 111, 112, 113 are contacted by the fluid.
  • At least one heating element 110, 111, 1 12, 113, a catalyst is arranged and is heated there.
  • the catalyst can be connected directly or indirectly to the heating elements 110, 111, so that these heating elements represent the catalyst support or a support for the catalyst support.
  • the heat supply of the reaction takes place electrically and is not introduced from the outside by means of radiation through the walls of the reactor, but directly into the interior of the reaction space. It is realized a direct electrical heating of the catalyst.
  • heating elements 110, 111, 112, 113 are preferably Bankleiterlegtechniken such as FeC Al alloys are used.
  • metallic materials it is also possible to use electrically conductive Si-based materials, particularly preferably SiC, and / or carbon-based materials.
  • At least one, for example, ceramic intermediate level 200, 201, 202 (which is preferably supported by a ceramic or metallic support frame, plane) is arranged between two heating levels 100, 101, 102, 103, the intermediate level (s) being 200, 201, 202 or the Inh alt 210, 21 1, 212 an intermediate level 200, 201, 202 are also flowed through during operation of the reactor of the fluid. This has the effect of homogenizing the fluid flow. It is also possible that additional catalyst is present in one or more intermediate levels 200, 201, 202 or other isolation elements in the reactor. Then an adiabatic reaction can take place. The pressure in the reactor can take place via a pressure-resistant steel jacket.
  • the electrical connections are shown in FIG. 1 only shown very schematically. They can be performed in the cold area of the reactor within an insulation to the ends of the reactor or laterally from the heating elements 1 10, 1 1 1, 1 12, 1 13 performed so that the actual electrical connections can be provided in the cold region of the reactor.
  • the electrical heating is done with direct current or alternating current.
  • inlet temperatures are often reached by 600 ° C, which are often below the desired inlet temperatures that reduce the formation of carbon black / carbon in reforming reactions.
  • the connection of one or more of the described electrically heated elements as a gas heater allows a rapid heating of the educt gases to temperatures higher than usual in the prior art, without an oxygen-containing atmosphere is required.
  • the use of the electrically heated elements in the inlet region of the reactor also has a positive effect with regard to the cold start and starting behavior, in particular with regard to rapid heating to the reaction temperature and better controllability.
  • heating elements 1 10, 1 1 1, 1 12, 1 13 are arranged, which are constructed in a spiral, meandering, lattice-shaped and / or reticulated.
  • At least one heating element 1 10, 1 1 1, 1 12, 1 13 one of the other heating elements 1 10, 1 1 1, 1 12, 1 13 different amount and / or type of catalyst is present.
  • the heating elements 110, 111, 112, 113 are arranged so that they can each be electrically heated independently of each other.
  • the individual heating levels can be individually controlled and regulated.
  • In the reactor inlet area can be dispensed with a catalyst in the heating levels as needed, so that only the heating and no reaction takes place in the inlet area. This is particularly advantageous in terms of starting the reactor.
  • a temperature profile adapted for the respective reaction can be achieved. With regard to the application for endothermic equilibrium reactions, this is, for example, a temperature profile which achieves the highest temperatures and thus the highest conversion at the reactor outlet.
  • the (for example ceramic) intermediate levels 200, 201, 202 or their contents 210, 211, 212 comprise a material which is resistant to the reaction conditions, for example a ceramic foam. They serve for mechanical support of the heating levels 100, 101, 102, 103 and for mixing and distribution of the gas stream. At the same time an electrical insulation between two heating levels is possible. It is preferred that the material of the content 210, 21 1, 212 of an intermediate level 200, 201, 202 comprises oxides, carbides, nitrides, phosphides and / or borides of aluminum, silicon and / or zirconium. An example of this is SiC. Further preferred is cordierite.
  • the intermediate level 200, 201, 202 may include, for example, a loose bed of solids. These solids themselves may be porous or solid, so that the fluid flows through gaps between the solids. It is preferred that the material of the solid bodies comprises oxides, carbides, nitrides, phosphides and / or borides of aluminum, silicon and / or zirconium. An example of this is SiC. Further preferred is cordierite.
  • the intermediate plane 200, 201, 202 comprises a one-piece porous solid.
  • the fluid flows through the intermediate plane via the pores of the solid. This is shown in FIG. 1 shown.
  • Preference is given to honeycomb monoliths, as used for example in the exhaust gas purification of internal combustion engines.
  • the average length of a heating level 100, 101, 102, 103 is viewed in the direction of flow of the fluid and the average length of an intermediate level 200, 201, 202 in the direction of flow of the fluid is in a ratio of> 0.01: 1 to ⁇ 100: 1 to each other. Even more advantageous are ratios of> 0, 1: 1 to ⁇ 10: 1 or 0.5: 1 to ⁇ 5: 1.
  • Suitable catalysts can be selected for example from the group consisting of: (I) the mixed metal oxide of the formula A (i -w- x) A 'W A' ' ⁇ ⁇ (i -y - z) B' y B "z 03- ⁇ kita where:
  • A, A 'and A are independently selected from the group: Mg, Ca, Sr, Ba, Li, Na, K, Rb, Cs, Sn, Sc, Y, La, Ce, Pr, Nd, Pm, Sm , Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Tl, Lu, Ni, Co, Pb, Bi and / or Cd; and
  • B, B 'and B are independently selected from the group: Cr, Mn, Fe, Bi, Cd, Co, Cu, Ni, Sn. Al, Ga, Sc, Ti, V, Nb, Ta, Mo, Pb , II f Zr, Tb W, Gd Yb Mg, Li Na, K. Ce and / or Zn, and
  • A, ⁇ 'and A are independently selected from the group: Mg, Ca, Sr, Ba, Li, Na, K, Rb, Cs, Sn, Sc, Y, La, Ce, Pr, Nd, Sm, Eu , Gd, Tb, Dy, Ho, Er, Tm, Yb, Tl, Lu, Ni, Co, Pb and / or Cd, and
  • B is selected from the group: Cr, Mn, Fe, Bi, Cd, Co, Cu, Ni, Sn, Al, Ga, Sc, Ti, V, Nb, Ta, Mo, Pb, 11 f. Zr, Tb. W, Gd, Yb, Mg, Cd, Zn, Re, Ru. Rh, Pd, Os, Ir and / or Pt; and
  • B ' is selected from the group: Re, Ru, Rh, Pd, Os, Ir and / or Pt;
  • B is selected from the group: Cr, Mn, Fe, Bi, Cd, Co, Cu, Ni, Sn, Al, Ga, Sc, Ti, V, Nb, Ta, Mo, Pb, I i, Zr, Tb W, Gd Yb, Mg, Cd and / or Zn, and
  • Ml and M2 are independently selected from the group: Re, Ru, Rh, Ir, Os, Pd and / or Pt; and M3 is selected from the group: Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd. Tb, Oy, i l. He, Tm,
  • L is selected from the group: Na, K, Rb, Cs, Mg, Ca, Sr, Ba, Sc, Y, Sn, Pb, Pd, Mn, In, Tl, La, Ce, Pr, Nd, Sm, Eu , Gd, Tb, Dy, Ho, Er, Tm, Yb and / or Lu; and
  • M is selected from the group: Ti, Zr, I i f. V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Ru, Os, Co,
  • I. is selected from the group: Na, K. Rb. Cs, Mg, Ca, Sr, Ba. Sc, Y. Sn, Pb. Mn. in. Tl,
  • Ml and M2 are independently selected from the group: Cr, Mn, Fe, Co, Ni,
  • a and B are independently selected from the group: Be, Mg, Ca, Sc, Ti, V,
  • reaction products includes the catalyst phases present under reaction conditions.
  • the reactor can be modular.
  • a module can contain, for example, a heating level, an intermediate level, the electrical contacting and the corresponding further insulation materials and thermal insulation materials.
  • electrical heating of at least one of the liquor elements 110, 111, 112, 113 occurs in the reactor provided. This may, but need not, be timed prior to passage of a reactant comprising fluid through the flow reactor with at least partial reaction of the reactants of the fluid. As already mentioned in connection with the reactor, it is advantageous if the individual heating elements 110, 111, 112, 113 are operated with a respective different heating power.
  • the reaction temperature in the reactor is at least in places> 700 ° C to ⁇ 1300 ° C. More preferred ranges are> 800 ° C to ⁇ 1200 ° C and> 900 ° C to ⁇ 1100 ° C, especially> 850 ° C to ⁇ 1050 ° C.
  • the average (average) contact time of the fluid to a heating element 11 10, 11 1, 12, 13 may, for example, be> 0.01 second to ⁇ 1 second and / or the average contact time of the fluid to an intermediate level 110, 111, 112 , 113 may be, for example,> 0.001 seconds to ⁇ 5 seconds.
  • Preferred contact times are> 0.005 to ⁇ 1 second, more preferably> 0.01 to ⁇ 0.9 seconds.
  • the reaction can be carried out at a pressure of> 1 bar to ⁇ 200 bar.
  • the pressure is> 2 bar to ⁇ 50 bar, more preferably> 6 bar to ⁇ 30 bar.
  • the reactants in the fluid are selected from the group comprising alkanes, A icon, alkynes, alkanols, alkenols, alkynols, carbon monoxide, carbon dioxide, water, ammonia, hydrogen and / or oxygen.
  • alkanes methane is particularly suitable, among the alkanols methanol and / or ethanol are preferred.
  • FIG. Figure 2 shows another reactor which can preferably be used for the RWGS reaction.
  • the first heating level 100 with heating element 1 10 is not yet provided with a catalyst and serves as a gas heater.
  • the subsequent intermediate level 200 contains a monolithic shaped catalyst body 210, which is catalytically coated. Alternatively, it may also be a catalyst bed.
  • this heating bath 1 02 is again an intermediate layer 202 with monolithic catalyst shaped body or catalyst bed 212, a heating level 103 with heating element 1 13 and intermediate cell 203 with mo nelithi cal cata lysis Atorformk örp er o the catalyst bed 213. At least one of the heating elements 1 1 1, 1 12 and 1 13 also includes a catalyst.
  • the individual catalyst-carrying elements of the reactor can differ in the type and amount of the catalyst and the heating elements can be controlled and regulated individually or in groups.
  • the characteristics of the RWGS reaction lie in a comparatively moderate heat requirement and in the fact that it is an equilibrium reaction.
  • methanation may occur especially at elevated pressure and at temperatures below 800 ° C. Therefore, a high gas inlet temperature is preferably selected in order to thermodynamically suppress the side reactions and in particular the methanation. In turn, a high outlet temperature ensures high sales.
  • the kataiytician implementation takes place here for the most part adiabatically to the monolithic catalyst moldings and to a lesser extent to the catalyst provided with heating elements.
  • FIG. 3 shows a further reactor which can preferably be used for dry reforming.
  • the first heating level 100 with heating element 1 10 can not yet be provided with a catalyst and then serves as a pure gas heater. In order to avoid unwanted side reactions, however, a (weakly) catalytically active layer may already be applied to the heating element 110.
  • the subsequent intermediate level 200 contains a porous support layer 210, which may optionally be catalytically coated. This is followed by a heating level 101 with a catalytically coated heating element 11 1 1, an intermediate level 201 with a porous support layer 21 1 (optionally catalytically coated) and a further heating level 1 02 with a catalytically coated heating element 1 12.
  • this heating level 102 Downstream of this heating level 102 is again an intermediate level 202 with a porous support layer 212 (optionally catalytically coated), a heating level 103 with catalytically coated heating element 1 13 and an intermediate level 203 with a porous support layer 213 (optionally catalytically coated).
  • the individual catalyst-carrying elements of the reactor can differ in the type and amount of the catalyst and the heating elements can be controlled and regulated individually or in groups.
  • the main feature of the Dry Reforming lies in a high heat demand, which prevails locally limited, especially in the first third of the reactor. It is an equilibrium reaction with a Rußbi tion as a side reaction. Therefore, it is preferred to choose high gas inlet temperatures to thermodynamically suppress the side reaction. High outlet temperatures ensure high sales. The reaction takes place essentially on the catalytically coated heating elements.
  • FIG. 4 shows a further reactor, which can preferably be used for methane steam reforming.
  • the first heating level 100 with heating element 1 10 can not yet be provided with a catalyst and then serves as a pure gas heater. In order to avoid unwanted side reactions, however, a (weakly) catalytically active layer may already be applied to the heating element 110.
  • the subsequent intermediate level 200 contains a porous support layer 210, which may optionally be catalytically coated. This is followed by a heating level 101 with a catalytically coated heating element 1 1 1, an intermediate level 201 with a porous support layer 211 (optionally catalytically coated) and a further heating level 102 with a catalytically coated heating element 1 12.
  • this heating level 102 Downstream of this heating level 102 is again an intermediate level 202 with a porous support layer 212 (optionally catalytically coated), a heating level 103 with catalytically coated heating element 1 13 and an intermediate level 203 with monolithic shaped catalyst body or catalyst bed 213.
  • the individual catalyst-carrying elements of the reactor can differ in the type and amount of the catalyst and the heating elements can be controlled and regulated individually or in groups.
  • the main feature of methane steam reforming is a high heat requirement. It is an equilibrium reaction with a soot formation as a side reaction. Therefore, it is preferred to choose high gas inlet temperatures to thermodynamically suppress the side reaction. I boil outlet temperatures ensure a high turnover.
  • the reaction is carried out essentially in the first reactor segment on the catalytically coated heating elements.
  • the first segment is characterized by the fact that the reactant concentration and the heat requirement of the reaction are very high.
  • the second segment of the reactor which is characterized by the fact that the reactant methane is already largely implemented and the volume-specific heat demand is significantly lower, the further reaction of the starting materials can be carried out on catalytically coated moldings.
  • the heating elements then act as an intermediate heater as needed.
  • the model includes a solid phase and a gas phase ⁇
  • the mass transfer between gas and catalyst is taken into account (linear driving force approach)
  • FIG. Figure 5 shows the conversion (Xcm, Xccc) over the normalized reactor length.
  • the "peaks" in the sales profile result from the consideration of a bypass flow, which is mixed in behind each heating element.
  • the turnover rises steadily and reaches 90% after the first half of the reactor, then the turnover curve levels off and approaches the corresponding output Equilibrium value.
  • FIG. 6 shows the temperature profile of the gas and solid phase.
  • the maximum power of the heating elements is given up in the inlet area (corresponds to 100% in the power profile). Much of the electrical energy is consumed by the heat of reaction.
  • the power input is chosen so that the solid temperature (including the catalyst phase) is in the range around 1100 ° C.
  • the reaction gas enters the reactor at 800 ° C., and the temperature of the gas phase increases over the reactor length through heat exchange with the solid. The reaction takes place on the solid, reactions in the gas phase are not taken into account.
  • FIG. 7 shows the relative heating power per heating element.
  • the profile of heat input per element shows that the highest power is introduced in the first third of the reactor. At the rear of the reactor, sales level off and only a small input of power is required. From this derive the concepts that provide in the field of monolithic shaped body or catalyst bed.
  • FIG. 8 shows the conversion (Xcm, Xco2) over the normalized reactor length
  • FIG. 9 shows the temperature profile of the gas and solid phase
  • FIG. 10 shows the relative heating power per heating element.

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Abstract

L'invention concerne un réacteur à écoulement pour la réaction d'un fluide contenant un produit de départ, comportant, dans le sens d'écoulement du fluide, une pluralité de plans de chauffe (100, 101, 102, 103) chauffés électriquement au moyen d'éléments de chauffe (110, 111, 112, 113), les plans de chauffe (100, 101, 102, 103) pouvant être parcourus par le fluide, un catalyseur étant situé sur au moins un élément de chauffe (110, 111, 112, 113) et pouvant y être chauffé. Au moins une partie d'une surface interne du réacteur en écoulement qui est en contact avec le fluide est conçue pour atteindre une température supérieure ou égale à 600 °C pendant le fonctionnement du réacteur à écoulement. Une quantité supérieure ou égale à 90% de matière de cette surface interne du réacteur à écoulement comprend un alliage Fe-Cr-Al. Un procédé permettant de faire fonctionner le réacteur à écoulement comporte les étapes suivantes : fourniture d'un réacteur à écoulement selon l'invention ; chauffe électrique d'au moins un des éléments de chauffe (110, 111, 112, 113) ; et circulation d'un fluide contenant un produit de départ dans le réacteur à écoulement avec réaction au moins partielle des produits de départ du fluide.
PCT/EP2013/054957 2012-03-13 2013-03-12 Réacteur à écoulement axial à base d'un alliage fe-cr-al WO2013135666A1 (fr)

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