Structured Catalyst

Abstract

A structured catalyst for catalyzing the endothermic reaction of a feed gas to convert it into a product gas is provided.

Description

Technical Field

[0001] Structured catalysts, reactor systems and processes are provided for conducting endothermic reactions of feed gases, wherein heat for the endothermic reactions is provided by resistive heating. Background Art

[0002] Syngas production is typically carried out in large chemical plants due to the energy-intensive reactions required to facilitate its production. This makes small-scale production difficult. In addition, the toxicity of syngas (particularly due to its carbon monoxide content) makes its storage difficult and poses significant risks.

[0003] In smaller plants, synthesis gas needs to be produced on demand. Summary of the invention

[0004] In a first aspect, a structured catalyst for catalyzing an endothermic reaction of a feed gas to convert it into a product gas is provided, the structured catalyst comprising at least one macroscopic structure extending from a first end to a second end in a longitudinal direction, wherein the first end forms an inlet of the macroscopic structure for the feed gas and the second end forms an outlet for the product gas, the macrostructure comprising a three-dimensional network structure, wherein the network structure forms a flow path allowing the feed gas to flow from the first end to the second end, wherein the network structure is formed of a conductive metal material and at least partially supports a ceramic coating, the ceramic coating supporting a catalytically active material, wherein the network structure constitutes a sub-fraction of a cross-section of the macroscopic structure in a cross-section transverse to the longitudinal direction, the sub-fraction being in the range of 4%-75%, and wherein the network structures in at least three different cross-sections along the longitudinal direction constitute different sub-fractions.

[0005] In another aspect, a reactor system for performing an endothermic reaction of a feed gas is provided, the reactor system comprising:

[0006] a) a structured catalyst according to the first aspect;

[0007] b) a pressure housing containing the structured catalyst, the pressure housing comprising an inlet for admitting the feed gas and an outlet for admitting the product gas, wherein the inlet is positioned such that the feed gas enters the structured catalyst at a first end and the product gas exits the catalyst from a second end; and

[0008] c) A heat insulation layer (heat insulation layer) between the structured catalyst and the pressure housing.

[0009] The term "endothermic reaction of the feed gas" is to be understood as a reaction scheme in which the conversion of the feed gas into the product gas requires energy to be supplied from its surroundings for its performance.

[0010] In yet another aspect, there is provided the use of the structured catalyst according to the first aspect or the reactor according to the second aspect, wherein the endothermic reaction(s) are selected from the group consisting of steam methane reforming, hydrogen cyanide formation, methanol cracking, ammonia cracking, reverse water gas shift and dehydrogenation.

[0011] Other aspects of the technology are set forth in the following detailed description, drawings, and appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1a shows a cross-section of an embodiment of a reactor system of the present invention having a structured catalyst comprising an array of macrostructures in cross-section;

[0013] Figure 1b Shows Figure 1a A reactor system wherein the insulation and a portion of the pressure shell are removed;

[0014] Figure 2 is an enlarged view of a portion of the reactor system;

[0015] Figure 3a-3f Different embodiments of cutouts of a mesh structure are shown;

[0016] Figure 4a-4c Different embodiments of cutouts of a mesh structure are shown;

[0017] Figure 5 An embodiment of a macrostructure is shown;

[0018] Figure 6a Shows Figure 5 Relative metal cross-sections of the embodiment shown in;

[0019] Figure 6b Shows Figure 5 The relative change in cross-sectional area per unit length of the embodiment shown in ;

[0020] Figure 6c Shows Figure 5 Relative current density of the embodiment shown in;

[0021] Figure 7 An embodiment of a macrostructure is shown;

[0022] Figure 8a Shows Figure 7 Relative metal cross-sections of the embodiment shown in;

[0023] Figure 8b Shows Figure 7 The relative change in cross-sectional area per unit length of the embodiment shown in ;

[0024] Figure 8c Shows Figure 7 Relative current density of the embodiment shown in;

[0025] Fig. 9 An embodiment of a macrostructure is shown;

[0026] Fig.10a Shows Fig. 9 Relative metal cross-sections of the embodiment shown in;

[0027] Fig.10b Shows Fig. 9 The relative change in cross-sectional area per unit length of the embodiment shown in ;

[0028] Fig.10c Shows Fig. 9 Relative current density of the embodiment shown in;

[0029] Fig.11 An embodiment of a macrostructure is shown;

[0030] Fig.12a Shows Fig.11 Relative metal cross-sections of the embodiment shown in;

[0031] Figure 12b Shows Fig.11 The relative change in cross-sectional area per unit length of the embodiment shown in ;

[0032] Fig.12c Shows Fig.11 Relative current density of the embodiment shown in;

[0033] Fig.13 An embodiment of a macrostructure is shown;

[0034] Fig.14a Shows Fig.13 Relative metal cross-sections of the embodiment shown in;

[0035] Fig.14b Shows Fig.13 The relative change in cross-sectional area per unit length of the embodiment shown in ;

[0036] Fig.14cShows Fig.13 Relative current density of the embodiment shown in;

[0037] Fig.15 It shows Figure 5 , Figure 7 , Fig. 9 , Figure 1 and Fig.13 A graph of the increase in resistance of the embodiment shown in ;

[0038] Fig.16a and Fig.16b showing different views of embodiments of structured catalysts;

[0039] Fig.17 An example of a structured catalyst is shown;

[0040] Figure 18a-Figure 18c Shown through Fig.17 Different cross sections of the embodiment shown in;

[0041] Fig.18d Shows Fig.17 Relative metal cross-sections of the embodiment shown in;

[0042] Fig.19a An example of a structured catalyst is shown;

[0043] Fig.19b Shown through Fig.19a A cross section of an embodiment of a structured catalyst is shown in FIG.

[0044] Fig. 20 An example of a structured catalyst is shown;

[0045] Fig.21 An example of a structured catalyst is shown;

[0046] Fig.22a Two examples of structured catalysts are shown;

[0047] Figure 22b Shown through Fig.22a A cross section of an embodiment of a structured catalyst is shown in FIG.

[0048] Fig.23a An embodiment of a macrostructure is shown;

[0049] Figure 23b An example of a structured catalyst is shown;

[0050] Fig.24 An example of a structured catalyst is shown;

[0051] Fig.25 Embodiments of macrostructures and multiple arrays of macrostructures are shown;

[0052] Fig.26 Various embodiments of structured catalysts are shown;

[0053] Fig. 27 An example of a structured catalyst is shown;

[0054] Fig.28 Different portions of an embodiment of a macrostructure are shown;

[0055] Fig.29a Different portions of an embodiment of a macrostructure are shown;

[0056] Fig.29b Different portions of an embodiment of a macrostructure are shown;

[0057] Fig.30a shows a portion of an embodiment of a macrostructure; and

[0058] Fig.30b Shows the assembly components Fig.30a The part shown in . DETAILED DESCRIPTION

[0059] Electrically heated reactors offer the possibility of making very compact chemical reactors as the heat for the reaction is transferred directly to the catalyst zone.

[0060] Compact electroreactors using monolithic catalysts can be easily operated and use simple start-up principles to produce gas when needed. This results in relatively cheap plants where only the required amount of gas can be produced and little or no gas storage is required, while also reducing or completely eliminating gas transportation. The simple reactor equipment and simple operation of the process make gas production attractive in delocalized plants, which reduces the risks of gas handling.

[0061] An embodiment of a compact electroreactor comprises a structured catalyst comprising a macrostructure comprising a three-dimensional mesh structure, wherein the mesh structure forms a flow path allowing a feed gas to flow from a first end to a second end of the macrostructure. By providing a mesh structure having alternating cross-sections along a longitudinal direction of the macrostructure, the resistance along the longitudinal direction can be controlled and optimized depending on the application, thereby enabling operation at increased heat flux or lower current. It can additionally improve mixing of the gas during its flow from the first end to the second end, thereby improving mass transfer performance.

[0062] Therefore, a structured catalyst for catalyzing an endothermic reaction of a feed gas to convert it into a product gas is provided, the structured catalyst comprising at least one macrostructure extending from a first end to a second end in a longitudinal direction, wherein the first end forms an inlet of the macrostructure for the feed gas and the second end forms an outlet for the product gas, the macrostructure comprising a three-dimensional mesh structure, wherein the mesh structure forms a flow path allowing the feed gas to flow from the first end to the second end, wherein the mesh structure is formed of a conductive metal material and at least partially supports a ceramic coating, wherein the ceramic coating supports a catalytically active material, wherein the mesh structure constitutes a sub-portion of a cross-section of the macrostructure in a cross-section transverse to the longitudinal direction, the sub-portion being in the range of 4%-75%, and wherein the mesh structures in at least three different cross-sections along the longitudinal direction constitute different sub-portions.

[0063] The mesh structure constitutes a sub-portion of the cross section of the macrostructure in a cross section transverse to the longitudinal direction. Thus, the mesh structure constitutes one portion of the cross section and the openings constitute another portion of the same cross section. It should be understood that the openings may be at least partially filled with a material different from the metal material forming the mesh structure.

[0064] The sub-portion is in the range of 4%-75%. In each cross section along the longitudinal direction of the macrostructure, the mesh structure may constitute a sub-portion of the cross section of the macrostructure, the sub-portion being in the range of 4%-75%. Preferably, the sub-portion is in the range of 4%-50%, even more preferably in the range of 4%-30%.

[0065] The macrostructure is formed such that the mesh structure in at least three different cross sections along the longitudinal direction constitutes different subsections, whereby the mesh structure forms at least three different subsections along the longitudinal direction of the macrostructure.

[0066] As an example, the macrostructure may comprise a mesh structure which constitutes a sub-portion of 5% in one cross section, a sub-portion of 15% in another cross section and a sub-portion of 25% in a third cross section.

[0067] Another macrostructure may include a mesh structure that forms a 7% sub-portion in one cross-section, a 30% sub-portion in another cross-section, and a 48% sub-portion in a third cross-section.

[0068] It should be understood that the above-described macrostructures are examples of macrostructures, and other macrostructures may include a mesh structure of another set of sub-portions.

[0069] It should also be understood that the mesh structure in the fourth cross section can constitute the same sub-portion as the sub-portion of one of the first cross section, the second cross section or the third cross section. As an example, the mesh structure of the first embodiment mentioned can constitute a 15% sub-portion in the fourth cross section as in the second cross section.

[0070] However, in another embodiment, the mentioned mesh structure of the first embodiment may constitute a sub-portion of 28% in the fourth cross section; ie, a sub-portion different from the sub-portions of the first, second and third cross sections.

[0071] In different embodiments, the cross-section of the mesh structure may constitute at least 4, preferably 5, more preferably 6, more preferably 7, more preferably 8, more preferably 9, more preferably 10, more preferably 11, and most preferably 12 subsections along the longitudinal direction. Thus, the number of subsections may vary from an embodiment comprising three subsections to an embodiment comprising several subsections, such as 12 subsections or even more.

[0072] When a subsection in the cross section is reduced, the resistance per unit volume will increase, enabling operation at increased heat flux or lower current. By steadily reducing the cross section, the heat flux can be adapted to the activity of the chemical reaction, similar to the increased temperature in the structure, thereby increasing the reaction rate of the catalytic reaction. Furthermore, the concept allows for the creation of compact arrays where the increased resistance means that the heat flux can be balanced with the chemical reaction based on the available surface area. Altogether, this means that an overall minimum material usage can be achieved for a given array design without the risk of unwanted hot spots or runaway reactions.

[0073] Furthermore, the variation of the subsections can be used to disrupt the gas flow and in this way improve the mixing of the gas flow for better mass transfer performance, since the openings in the mesh structure are able to mix the gas flowing from the first end to the second end of the macrostructure.

[0074] As exemplified by the above embodiments, the subsections may vary in number and size, thereby enabling local variations in current density and, therefore, heat flux. It is an object of the invention to make such variations in a controlled manner so as not to create undesirable hot spots in the structure due to abrupt variations in the subsections.

[0075] A macrostructure including a mesh structure having cross sections forming different subsections can achieve higher resistance at some areas without generating high current density in local areas. Thus, the performance of a given volume of the macrostructure can be maximized without the risk of hot spots generating undesirable side reactions or potential mechanical failures.

[0076] In one embodiment of the invention, the subsections are controlled in such a way that the electrical resistance and therefore the local heat flux is greatest in the middle portion of the macrostructure in the longitudinal direction, and is lower in the first and second ends. Having a lower heat flux in the first end can be advantageous, where the reactant gases are far from equilibrium and undesirable side reactions can be a problem. In addition, if the heat flux is lower, temperature-sensitive electrical connection components (such as wires, connectors, bus bars, etc.) can be more easily used in the first section. Having a lower heat flux in the second end can be advantageous to allow the chemical reaction to achieve a conversion closer to chemical equilibrium, thereby avoiding unnecessary overheating of the product gases. Having a lower heat flux in the second end can also be advantageous due to controlling the current path and avoiding overheating of the material in this end where the temperature is already high.

[0077] The macrostructure may have a resistance higher than a similar macrostructure without the mesh structure by more than 20%, preferably more than 50%, more preferably more than 100%, even more preferably more than 300%. Depending on the size and layout of the macrostructure, the resistance may be even higher.

[0078] The mesh structure is formed of a metal material, which may be an alloy including one or more substances selected from the group consisting of Fe, Cr, Al, Co, Ni, Zr, Cu, Ti, Mn, and Si.

[0079] The macrostructures support a catalytically active material, which may be provided at least in part on exposed surface areas of the macrostructures.

[0080] The close proximity between the catalytically active material and the macrostructure enables efficient heating of the catalytically active material by heat conduction from the solid material of the resistively heated macrostructure. Therefore, an important feature of the resistive heating process is that the energy is supplied inside the object itself, rather than from an external heat source via heat conduction, convection and / or radiation. In addition, the hottest part of the reactor system including the structured catalyst will be within the pressure shell of the reactor system. Preferably, the size of the power supply and the structured catalyst is determined so that at least a portion of the structured catalyst reaches a temperature of 850°C, preferably 900°C, more preferably 1000°C or even more preferably 1100°C. The amount and composition of the catalytically active material can be adapted to the endothermic reaction under given operating conditions. The surface area of ​​the macrostructure, the sub-portion of the macrostructure coated with the ceramic coating, the type and structure of the ceramic coating, and the amount and composition of the catalytically active catalyst material can be adapted to the endothermic reaction under given operating conditions. However, it should be noted that, advantageously, substantially all surfaces of the macrostructure are coated with the ceramic coating, and preferably all or most of the ceramic coating supports the catalytically active material. Preferably, only the portion of the macrostructure connected to the conductor is not provided with a ceramic coating.

[0081] As used herein, the term "macrostructure" means a structure that is large enough to be visible to the naked eye without a magnifying device. The size of the macrostructure is generally in the range of tens of centimeters or tens of meters. It is advantageous to make the size of the macrostructure correspond at least in part to the internal dimensions of the pressure shell that accommodates the structured catalyst, thereby saving space for the insulation layer and the conductor. In order to provide a macrostructure array with at least one of the external dimensions within a range of several meters (such as 0.5m, 1m, 2m or 5m), two or more macrostructures can be connected. Such two or more macrostructures can be expressed as a "macrostructure array". In this case, it is advantageous to make the size of the macrostructure array correspond at least in part to the internal dimensions of the pressure shell that accommodates the structured catalyst (saving space for the insulation layer). Conceivable macrostructure arrays can occupy 0.01m 3 Up to 10m 3 Or even larger volumes. A "structured catalyst" may include a single macrostructure or an array of macrostructures, wherein the (one or more) macrostructures may support a ceramic coating that supports a catalytically active material. If the structured catalyst includes an array of macrostructures, the macrostructures may be electrically connected to each other; however, alternatively, the macrostructures are not electrically connected to each other. Thus, a structured catalyst may include two or more macrostructures positioned adjacent to each other, or two or more arrays positioned adjacent to each other.

[0082] The physical dimensions of the macrostructures may be of any suitable dimensions; thus, the height of a macrostructure may be smaller than its width, and vice versa.

[0083] The term "first end of the macrostructure" is intended to mean the end of the macrostructure where the feed gas enters the macrostructure, and the term "second end of the macrostructure" is intended to mean the end of the macrostructure where the product gas exits the macrostructure.

[0084] The macrostructure may support a ceramic coating, wherein the ceramic coating may support a catalytically active material. The term "macrostructure supporting a ceramic coating" is intended to mean that the macrostructure is coated with a ceramic coating at least at a portion of the surface of the macrostructure. Thus, the term does not mean that all surfaces of the macrostructure are coated with a ceramic coating; in particular, at least the portion of the macrostructure that is electrically connected to the conductor has no coating thereon. The coating may be a ceramic material having pores in the structure that allow the catalytically active material to be supported on and within the coating. Advantageously, the catalytically active material comprises catalytically active particles having a size ranging from about 5 nm to about 250 nm.

[0085] The macrostructure can advantageously be produced by 3D printing. The manufacture of the macrostructure can also include sintering the 3D printed element. A ceramic coating that may contain a catalytically active material can be provided to the macrostructure before a second sintering in an oxidizing atmosphere so as to form a chemical bond between the ceramic coating and the macrostructure. Alternatively, the catalytically active material can be impregnated into the ceramic coating after the second sintering. When a chemical bond is formed between the ceramic coating and the macrostructure, a high thermal conductivity between the electrically heated macrostructure and the catalytically active material supported by the ceramic coating can be achieved, thereby providing close and almost direct contact between the heat source and the catalytically active material of the structured catalyst. Due to the close proximity between the heat source and the catalytically active material, heat transfer is efficient, so that the structured catalyst can be heated very efficiently. Therefore, a compact reactor system is possible in terms of gas processing per reactor system volume, and therefore the reactor system accommodating the structured catalyst can be compact.

[0086] As used herein, the terms "3D printing" and "3D printing" are intended to refer to metal additive manufacturing processes. Such metal additive manufacturing processes encompass 3D printing processes in which materials are joined to structures under computer control to create a three-dimensional object, wherein the structure will be solidified, for example by sintering, to provide a macrostructure. In addition, such metal additive manufacturing processes encompass 3D printing processes that do not require subsequent sintering, such as powder bed fusion or direct energy deposition processes. Examples of such powder bed fusion or direct energy deposition processes are laser beam, electron beam or plasma 3D printing processes.

[0087] The conductive material comprises Fe, Ni, Cu, Co, Cr, Al, Si or an alloy thereof. Such alloys may include other elements such as Mn, Y, Zr, C, Co, Mo or a combination thereof. Preferably, the conductive material comprises Fe, Cr, Al or an alloy thereof. Such alloys may include other elements such as Si, Mn, Y, Zr, C, Co, Mo or a combination thereof. Preferably, the catalytically active material is a particle having a size of 2nm to 250nm. Preferably, the conductor and the conductive material are made of a material different from the conductive material. The conductor may be, for example, iron, nickel, aluminum, copper, silver or an alloy thereof. The ceramic coating is an electrically insulating material and will typically have a thickness in the range of about 100μm, for example 10μm to 500μm.

[0088] The conductive material used for the macrostructure is advantageously a coherent or consistently intra-connected material so as to achieve electrical conductivity throughout the conductive material, and thereby achieve thermal conductivity throughout the structured catalyst, in particular to provide heating of the catalyst material. By means of a coherent or consistently intra-connected material, a uniform distribution of current within the conductive material can be ensured, thereby ensuring a uniform distribution of heat within the structured catalyst. Throughout this article, the term "coherent" means synonymous with cohesiveness, and therefore refers to a consistently intra-connected or consistently connected material. The effect of the structured catalyst being a coherent or consistently intra-connected material is to obtain control of the connectivity within the material of the structured catalyst, and therefore to obtain control of the conductivity of the conductive material. It should be noted that even if the conductive material is further modified, such as providing a cutout space within a portion of the conductive material, the conductive material is still represented as a coherent or consistently intra-connected material.

[0089] Typically, when macrostructures are 3D printed, the pressure drop from the inlet to the outlet of the reactor system can be significantly reduced compared to reactors in which the catalyst material is in particle form.

[0090] In alternative embodiments, one or more macrostructures may be produced by bending, cutting and / or welding metal sheets. It should be understood that the structured catalyst may include 3D printed macrostructures and macrostructures produced by other methods such as bending, cutting or welding.

[0091] The macrostructure may also include a circumferential wall forming an inner space. The circumferential wall may be formed of a conductive metal material. In an alternative embodiment, the circumferential wall may be formed of a non-conductive material. The mesh structure may be arranged in the inner space. In a preferred embodiment, the macrostructure is substantially square in a cross section perpendicular to the longitudinal direction. However, it should be understood that at least one macrostructure may also have other cross-sectional shapes, such as triangles, circles, ellipses, pentagons, hexagons, other polygons, etc. Therefore, depending on the external shape of the macrostructure, the circumferential wall may be substantially square, triangles, circles, etc.

[0092] In one embodiment, the circumferential wall comprises no openings transverse to the longitudinal direction, thereby providing a closed side wall arranged circumferentially around the mesh structure. This helps to ensure a controlled airflow path through the macrostructure.

[0093] The cross-section of the mesh structure is continuously non-constant over a combined distance of at least 10%, preferably 20%, more preferably 30%, more preferably 40%, more preferably 50%, more preferably 60%, more preferably 70%, more preferably 80%, most preferably 90% of the length of the macrostructure in the longitudinal direction. Continuously non-constant is to be understood as a sub-portion that varies continuously over a combined distance of at least 10%, wherein the sub-portion variation is non-constant. Or in other words, the first derivative of the sub-portion with respect to the longitudinal direction is a non-constant and continuous function. A combined distance is to be understood as a distance that may consist of two or more discrete distances with a continuous non-constant sub-portion, which is interrupted by an intermediate distance, wherein the sub-portion is not continuously non-constant, for example constant.

[0094] The variation of the sub-portions in the longitudinal direction may be less than 500% / mm, preferably less than 100% / mm, even more preferably less than 50% / mm. Smaller variations lead to smaller disturbances of the current density in the structure and thus to less tendency for local hot spots to form.

[0095] It should be understood that the cross-section of the mesh structure may alternatively or additionally be continuously non-constant in a direction transverse to the longitudinal direction over a combined distance of at least 10%, preferably 20%, more preferably 30%, more preferably 40%, more preferably 50%, more preferably 60%, more preferably 70%, more preferably 80%, and most preferably 90% of the length of the macrostructure.

[0096] When providing a mesh structure comprising at least three different cross-sections with different sub-portions, it may be achieved that the resistance gradient in at least one area along the longitudinal direction is substantially higher than the average resistance gradient along the longitudinal direction.

[0097] Additionally and / or alternatively, it can be achieved that the resistance gradient in at least one region along the longitudinal direction is substantially lower than the average resistance gradient along the longitudinal direction.

[0098] The mesh structure may include a plurality of cutouts, wherein the cutouts may be filled with a cutout material having a lower conductivity than the metal material. The cutouts may be formed as part of a 3D printing process that may be used to form the mesh structure.

[0099] In one embodiment, the cutout material is a void. That is, the cutout can be empty, thereby providing an opening through which the gas can pass as it flows from the first end to the second end. These cutouts can increase mixing of the gas passing through the macrostructure.

[0100] In an alternative embodiment, the cutout material is a solid cutout material. Thus, the cutouts may be closed, thereby preventing mixing of gases flowing through the cutouts from the first end to the second end. The mesh structure may include cutouts filled with different materials, whereby a first cutout may be filled with a first cutout material and a second cutout may be filled with a second cutout material. In an embodiment, the solid cutout material at least partially supports a ceramic coating having a catalytically active material similar to the catalytically active material on the metallic material. In this embodiment, increased catalytic activity is achieved in parallel with controlling the electrical resistance of the material.

[0101] The solid cutout material may have thermomechanical properties substantially equivalent to those of the metal material forming the mesh structure. The thermomechanical property may be a coefficient of thermal expansion, thereby achieving substantially equal expansion of the mesh structure and the solid cutout material arranged in the cutout during use of the catalyst. Alternatively or additionally, the thermomechanical property may be tensile strength.

[0102] In one embodiment, the mesh structure may include one or more cutouts as voids and one or more cutouts filled with solid cutout material. Thus, the mesh structure may include a first subset of cutouts as voids and may include a second subset of cutouts filled with solid cutout material. It should be understood that a subset may include only a single cutout. It should also be understood that the cutouts of the second subset may be filled with different materials, such that a first cutout is filled with a first cutout material and a second cutout is filled with a second cutout material.

[0103] The cutouts may have a variety of shapes. As an example, at least one of the cutouts has a shape selected from the group consisting of a sphere, a disk, an ellipsoid, a droplet, a spiral, and a polyhedron such as a box, a pyramid, a diamond, and a rhombus.

[0104] In one embodiment, all the cutouts have the same shape, while in other embodiments, at least some of the cutouts have different shapes. As an example, the mesh structure may include a first set of cutouts that are disc-shaped and a second set of cutouts that have a spherical shape. Thus, the mesh structure may include cutouts, at least two of which have different forms and / or shapes.

[0105] The plurality of cutouts may be arranged equidistantly along the longitudinal direction of the macrostructure. In alternative embodiments, the cutouts may be arranged at varying distances along the longitudinal direction. It should also be understood that the mesh structure may include a plurality of cutouts arranged equidistantly along the longitudinal direction and a plurality of cutouts arranged at varying distances along the longitudinal direction. As an example, two sets of cutouts may be arranged parallel to each other along the longitudinal direction.

[0106] Furthermore, a plurality of cutouts may be arranged equidistantly transversely to the longitudinal direction.

[0107] In one embodiment, the first and second sets of cuts are positioned alternately along the longitudinal direction.The difference between the first and second sets of cuts may be in size and / or shape and / or the cut material that may fill the cuts.

[0108] In one embodiment, at least a portion of the mesh structure may be formed as a three-dimensional grid structure, thereby enabling gas to flow through the macrostructure from a first end to a second end along a flow path that is non-linear, ie, has non-linear streamlines.

[0109] In one embodiment, at least a portion of the mesh structure may form a plurality of parallel flow channels.

[0110] In one embodiment, the mesh structure can form a plurality of inner walls, which can be arranged in the inner space formed by the circumferential wall. A plurality of inner walls can form a plurality of flow channels from the first end to the second end. Therefore, the mesh structure can have a plurality of parallel channels, a plurality of non-parallel channels and / or a plurality of labyrinth channels, wherein the channels have walls defining the channels. Therefore, several different forms of macro structures can be used, as long as the surface area of ​​the structured catalyst exposed to the gas is as large as possible. In a preferred embodiment, the macro structure has parallel channels, because such parallel channels give the structured catalyst a very small pressure drop. In a preferred embodiment, the parallel longitudinal channels are inclined in the longitudinal direction of the macro structure. In this way, the gas molecules flowing through the macro structure will mainly tend to hit the walls in the channel, rather than just flowing directly through the channel without contacting the wall. In order to provide a macro structure with sufficient resistivity, the size of the channel should be appropriate. For example, the channel can be quadratic (as seen in a cross section perpendicular to the channel), and the side length of the square is between 1 mm and 3 mm; however, it is conceivable that the maximum extent of the cross section can be up to about 4 cm. The wall may for example have a thickness between 0.2 and 2 mm, such as about 0.5 mm, and the ceramic coating supported by the wall may have a thickness between 10 and 500 μm, such as between 50 and 200 μm, such as 100 μm.

[0111] The macrostructure may include flow guides to ensure flow distribution of the gas flowing from the inlet at the first end toward the outlet at the second end. These flow guides may be 3D printed integrally with the macrostructure. The flow guides may form part of the mesh structure and may be 3D printed as part of the mesh structure.

[0112] In one embodiment, the guides may be evenly distributed along the longitudinal direction of the macrostructure, while in another embodiment, they may be unevenly distributed. It should also be understood that in one embodiment, the guides may be arranged along a portion of the longitudinal direction, and in an alternative embodiment, the guides may be arranged along the entire length of the macrostructure in the longitudinal direction.

[0113] The current guides may additionally serve as electrical terminals, which may minimize contact resistance, thereby providing a more uniform current distribution.

[0114] The structured catalyst may include two or more macrostructures, wherein at least two of the macrostructures are electrically connected, thereby forming an array including the two or more macrostructures.

[0115] Two adjacent macrostructures can be produced as a single piece by 3D printing, and an electrical connection is formed between the two macrostructures closest to the first end or the second end of these macrostructures. That is, the electrical connection can be in the region of the first end or the second end of the macrostructure.

[0116] In a specific embodiment of the structured catalyst of the present invention, the electrical connection between the first macrostructure and the second macrostructure is performed by mechanical connection, clamping, soldering, welding or any combination of these connection methods.

[0117] In a specific embodiment of the structured catalyst of the present invention, the electrical connection between the first macrostructure and the second macrostructure is in the form of a connector, the connector comprising at least two engaging means, each engaging means engaging one of the first macrostructure and the second macrostructure, wherein the engaging means has an inner surface whose shape matches at least a portion of the outer surface of the first macrostructure and the second macrostructure, and wherein the engaging means is attached to the outer surface of the circumferential wall by an interference fit. In the context of the present invention, an "interference fit" (also referred to as a press fit or a friction fit) is understood as a fastening between two tightly fitting mating parts, thereby producing a joint (joint) held together by friction after the parts are pushed / pressed together. The connector and one or more macrostructures can be joined by applying a forced pressure from, for example, a press on one part to make it slide over / into another part. In a specific embodiment, the connector is formed by an alloy comprising one or more substances selected from the group consisting of Fe, Cr, Al, Co, Ni, Zr, Cu, Ti, Mn and Si.

[0118] In a specific embodiment of the structured catalyst of the present invention, the electrical connection between the first macrostructure and the second macrostructure is in the form of a bridge of conductive material, wherein the bridge forms a coherent structure together with the first macrostructure and the second macrostructure. Here, "coherent" means forming a continuous phase. In a specific embodiment, the bridge is formed by providing the first macrostructure, the second macrostructure and the conductive material of the bridge in the form of three separate entities, and joining the separate entities together by a method including a sintering or oxidation treatment step. In a specific embodiment, the combination of the bridge and the first macrostructure and the second macrostructure is 3D printed and then sintered. In a specific embodiment, the conductive material of the bridge is an alloy including one or more substances selected from the group consisting of Fe, Cr, Al, Co, Ni, Zr, Cu, Ti, Mn and Si. In a specific embodiment, the conductive material of the bridge and the first macrostructure and the second macrostructure is the same.

[0119] In one embodiment, the structured catalyst may include at least a first macrostructure and a second macrostructure, wherein the second macrostructure may be arranged to at least partially circumferentially surround the first macrostructure. In one embodiment, the second macrostructure may be an elongated structure extending in the longitudinal direction and is hollow, thereby completely surrounding the first macrostructure, whereby the inner surface of the second macrostructure faces the outer surface of the first macrostructure. In an alternative embodiment, the second macrostructure may be arranged to partially circumferentially surround the first macrostructure, whereby a portion of the inner surface of the second macrostructure faces a portion of the outer surface of the first macrostructure. As an example of the latter embodiment, the first macrostructure may be formed in a substantially circular form in a second cross-section transverse to the longitudinal direction, and the second macrostructure may be substantially C-shaped in a cross-section transverse to the longitudinal direction, thereby partially surrounding the first macrostructure when arranged to partially circumferentially surround the first macrostructure.

[0120] The second macrostructure may be arranged to circumferentially surround at least 50% of the outer surface of the first macrostructure, such as at least 60%, such as at least 70%, such as at least 80%, such as at least 90%, such as 100%. When the second macrostructure is arranged to circumferentially surround 50% of the outer surface of the first macrostructure, half of the outer surface of the first macrostructure faces the second macrostructure, while the other 50% of the outer surface of the first macrostructure does not face the second macrostructure.

[0121] The first macrostructure and the second macrostructure can be electrically connected at the second end, whereby the structured catalyst can be configured to direct current to flow through the first macrostructure from the first end to the second end and then through the second macrostructure from the second end to the first end, while the second macrostructure is arranged to circumferentially surround the first macrostructure.

[0122] The first macrostructure and the second macrostructure may be formed integrally, and in an alternative embodiment may be formed as two separate elements, which may subsequently be connected to each other at the second end, thereby providing an electrical connection between the first macrostructure and the second macrostructure.

[0123] To facilitate the arrangement of the second macrostructure at least partially around the first macrostructure, the outer surface of the first macrostructure may match the inner surface of the second macrostructure. It should be understood that the shapes may match, while the sizes may be different to ensure that the first macrostructure and the second macrostructure are not arranged in contact with each other along their longitudinal direction. The first macrostructure and the second macrostructure may be electrically connected at the second end to allow current to flow through the first macrostructure and the second macrostructure.

[0124] By providing a first macrostructure with an outer surface that matches an inner surface of a second macrostructure, the distance between the first macrostructure and the second macrostructure can be minimized.

[0125] In one embodiment, in a cross section transverse to the longitudinal direction, the outer surface of the first macrostructure can be substantially circular. In a cross section transverse to the longitudinal direction, at least a portion of the outer surface of the second macrostructure can also be substantially circular. In an alternative embodiment, in a cross section transverse to the longitudinal direction, the outer surface of the first macrostructure can be substantially elliptical, square, triangular, pentagonal, hexagonal or other polygonal shape. Therefore, the outer surface can have any arbitrary shape. At least a portion of the inner surface of the second macrostructure can also form any of the shapes or a section of such a shape. The latter is particularly relevant in embodiments in which the second macrostructure is arranged to partially circumferentially surround the first macrostructure.

[0126] The first macrostructure and the second macrostructure may be arranged substantially coaxially.

[0127] It should be understood that the structured catalyst may additionally include a third macrostructure that may be arranged to at least partially circumferentially surround the second macrostructure. The second macrostructure and the third macrostructure may be connected at a first end, whereby the structured catalyst may be configured to direct current to flow through the first macrostructure from the first end to the second end, then through the second macrostructure from the second end to the first end, and then through the third macrostructure from the first end to the second end.

[0128] The first macrostructure, the second macrostructure and the third macrostructure may be arranged substantially coaxially.It should be understood that the above description of the relative shapes and sizes of the first macrostructure and the second macrostructure is also applicable to the second macrostructure and the third macrostructure.

[0129] It is also understood that the structured catalyst may include even more macrostructures, such as four, five or even more.

[0130] The two macrostructures may include parallel external segments to enable geometrical engagement between the two macrostructures in the longitudinal direction or in a direction transverse to the longitudinal direction. As an example, the parallel external segments may form part of a mesh structure, it may form part of a circumferential wall, or it may be a separate element attached to each macrostructure. In one embodiment, a portion of the parallel structures is a separate element attached to one of the macrostructures, while another portion of the parallel structures forms part of the other macrostructure.

[0131] The two macro structures can be held together by welding, soldering or mechanical pressing. When pressed together, friction forces can ensure that the two macro structures are held together.

[0132] At least one macrostructure may comprise an attachment section to allow direct attachment of an electrical connection, wherein the attachment section is 3D printed integrally with the macrostructure.An electrical connection may be provided to allow power to be supplied from a power source.

[0133] The thickness of the circumferential wall in the section providing electrical connection to the second macrostructure may be 25%, preferably 50%, even more preferably 100%, even more preferably 200% higher than the average thickness of the circumferential wall, wherein the thickness of the circumferential wall is defined as the dimension of the circumferential wall along a direction perpendicular to the longitudinal direction.

[0134] In one embodiment, the structured catalyst may be an array comprising a first macrostructure and a second macrostructure, wherein:

[0135] a) the first macrostructure and the second macrostructure include a three-dimensional network structure;

[0136] b) the array comprises at least a first conductor and a second conductor, the first conductor and the second conductor being electrically connected to the first macrostructure and the second macrostructure, respectively, and to a power source, wherein the power source is dimensioned to heat at least a portion of the first macrostructure and the second macrostructure to a temperature of at least 500° C. by passing an electric current through the macrostructures, and wherein the conductors are connected to the array at a location closer to the first end than to the second end,

[0137] c) the first macrostructure and the second macrostructure are electrically connected via a bridge of conductive material, and

[0138] d) The array is configured to direct current from the first conductor through the first macrostructure to the second end, then across the bridge, and then through the second macrostructure to the second conductor.

[0139] The array may be produced by a process of 3D printing the first macrostructure, the second macrostructure and the bridge as one entity.

[0140] Alternatively, the array may be produced by a process of 3D printing the first macrostructure, the second macrostructure, the bridge and the optional electrical connections as one entity.

[0141] In one embodiment, the second conductor is indirectly electrically connected to the second macrostructure.

[0142] The array may also include: (i) one or more juxtaposed additional intermediate macrostructures; and (ii) an end macrostructure, wherein each additional intermediate macrostructure is connected to at least two juxtaposed macrostructures by a bridge of conductive material, and wherein the end macrostructure is connected to at least one juxtaposed macrostructure, and wherein a second conductor is connected to the end macrostructure at a position on the end macrostructure that is closer to the first end than to the second end.

[0143] The first macrostructure and the second macrostructure may be connected by a bridge at a second end of the array.

[0144] A reactor system for performing an endothermic reaction of a feed gas is provided, the reactor system comprising:

[0145] a) a structured catalyst as described above;

[0146] b) a pressure housing containing the structured catalyst, the pressure housing comprising an inlet for admitting a feed gas and an outlet for admitting a product gas, wherein the inlet is positioned such that the feed gas enters the structured catalyst at a first end and the product gas exits the catalyst from a second end; and

[0147] c) A thermal insulation layer between the structured catalyst and the pressure housing.

[0148] It should be understood that the skilled person will readily recognize that any of the features described in conjunction with the structured catalyst may also be combined with a reactor system to perform an endothermic reaction of a feed gas, and vice versa.

[0149] The structured catalyst is very suitable for use in a reactor system for carrying out an endothermic reaction of a feed gas. Therefore, the above description of the structured catalyst is also applicable to the reactor system.

[0150] The layout of the reactor system allows for the feeding of pressurized feed gas to the reactor system at the inlet and the conduction of the gas into the pressure shell of the reactor system. Inside the pressure shell, the configuration of the insulation and inert material is arranged to conduct the feed gas through the passage of the structured catalyst, wherein the feed gas will contact the ceramic coating and the catalytically active material supported on the ceramic coating, wherein the catalytically active material will promote the endothermic reaction. In addition, the heating of the structured catalyst will supply the required heat for the endothermic reaction. The product gas from the structured catalyst is directed to the reactor system outlet.

[0151] When the pressure shell includes an inlet for allowing feed gas to enter and an outlet for allowing product gas to exit, wherein the inlet is positioned so that the feed gas enters the structured catalyst at a first end of the structured catalyst and the product gas exits the structured catalyst from a second end of the structured catalyst, and when the at least two conductors are connected to the structured catalyst at a location on the structured catalyst that is closer to the inlet than to the outlet, the at least two conductors can be placed in a relatively cool part of the reactor system. The first end of the structured catalyst has a lower temperature than the second end of the structured catalyst due to the following reasons:

[0152] - the feed gas directed through the inlet may cool the at least two conductors before being heated by the structured catalyst further along the path of the gas through the structured catalyst;

[0153] - the temperature of the feed gas entering the first end of the structured catalyst will be lower than the temperature of the product gas leaving the second end of the structured catalyst due to the heat supplied by the electricity to the structured catalyst,

[0154] - the endothermic nature of the reaction absorbs heat from its surroundings,

[0155] - The structured catalyst is configured to direct an electrical current from one conductor to substantially the second end of the structured catalyst and back to the second of the at least two conductors.

[0156] The temperature profile in the structured catalyst may correspond to a substantially continuously increasing temperature along the path of the feed gas through the structured catalyst.

[0157] When the reactor system of the present invention is used to promote the steam reforming reaction, it has several advantages over the more traditionally used fired tubular reformers. The reactor system of the present invention does not require a furnace, and this significantly reduces the overall reactor size. In addition, the advantage is that the amount of product gas produced in a single pressure shell is significantly increased compared to known tubular steam reformers. In a standard tubular steam reformer, the amount of product gas produced in a single tube of the tubular steam reformer is as high as 500 Nm 3 / h. In contrast, the reactor system of the present invention is arranged to produce up to or more than 2000 Nm in a single pressure shell. 3 / h, for example, even up to or greater than 10000Nm 3 / h (product gas). This can be done with no O2 in the feed gas and with less than 10% methane in the produced synthesis gas. When a single pressure vessel accommodates a total of 10,000 Nm 3 / h or more of product gas, it is no longer necessary to provide a plurality of pressure shells or means for distributing the feed gas to a plurality of such individual pressure shells.

[0158] Another advantage of the reactor system is that, since the structured catalyst comprises a macrostructure, the flow through the structured catalyst within the reactor system can be an upward flow. Alternatively, the flow through the structured catalyst can be in a horizontal direction or in any other suitable direction. This is more difficult in the case of reactors containing pellets due to the risk of fluidization, grinding and blowing out of the particles. Thus, a large amount of piping can be avoided, thereby reducing plant costs. Furthermore, the possibility of upward flow or horizontal flow increases the flexibility of plant design.

[0159] In addition, it should be noted that the term "at least two conductors are connected to the structured catalyst at a position on the structured catalyst that is closer to the first end of the structured catalyst than the second end of the structured catalyst" is intended to mean that all of the at least two conductors are connected closer to the first end of the structured catalyst than the second end. Preferably, at least two conductors are connected to the first end of the structured catalyst or within a quarter of the length of the macrostructure closest to the first end.

[0160] Use of the above structured catalyst or the above reactor is provided, wherein the endothermic reaction is selected from the group consisting of steam methane reforming, hydrogen cyanide formation, methanol cracking, ammonia cracking, reverse water gas shift and dehydrogenation.

[0161] The term "dehydrogenation" is intended to mean the following reaction:

[0162]

[0163] Wherein R1 and R2 can be any suitable group in a hydrocarbon molecule, such as -H, -CH3, -CH2, or -CH.

[0164] In one embodiment, the endothermic reaction is the dehydrogenation of hydrocarbons. The catalytically active material may be Pt. The maximum temperature of the reactor may be between 500° C. and 700° C. The pressure of the feed gas may be between 2 bar and 5 bar.

[0165] The term "water-gas shift" is intended to refer to the following reaction:

[0166]

[0167] In one embodiment, the endothermic reaction is a reverse water gas shift reaction (the reverse reaction of the water gas shift). The maximum temperature of the reactor may be between 600°C and 1300°C. The pressure of the feed gas may be between 2 bar and 80 bar, preferably between 10 bar and 40 bar. In one embodiment, the macrostructure is made of an alloy of Fe Cr Al, which supports a ceramic coating of a mixture of ZrO2 and Al2O3, wherein Mn is used as a catalytically active material. In another embodiment, the macrostructure is made of an alloy of Fe Cr Al, which supports a ceramic coating of a mixture of ZrO2 and MgAl2O4, wherein Ni is used as a catalytically active material.

[0168] The term "methanol cracking" is intended to mean the following reaction:

[0169]

[0170] Typically, the methanol cracking reaction is accompanied by a water-gas shift reaction.

[0171] In one embodiment, the endothermic reaction is the cracking of methanol. The maximum temperature of the reactor may be between 200°C and 300°C. The pressure of the feed gas may be between 2 bar and 30 bar, preferably about 25 bar. In one embodiment, the macrostructure is made of an alloy of FeCrAl, which supports a ceramic coating of a mixture of ZrO2 and Al2O3, with CuZn as the catalytically active material. In another embodiment, the macrostructure is made of an alloy of FeCrAl, which supports a ceramic coating of a mixture of ZrO2 and MgAl2O4, with Ni as the catalytically active material.

[0172] Furthermore, the term "steam reforming" is intended to mean a reforming reaction according to one or more of the following reactions:

[0173]

[0174] These reactions are also often coupled with the water-gas shift reaction.

[0175] In one embodiment, the endothermic reaction is steam reforming of hydrocarbons. The maximum temperature of the reactor may be between 850°C and 1300°C. The pressure of the feed gas may be between 5 bar and 180 bar, preferably about 25 bar. The catalytically active material may be Ni, Ru, Rh, Ir or a combination thereof, while the ceramic coating may be Al2O3, ZrO2, MgAl2O4, CaAl2O4 or a combination thereof, and may be mixed with oxides such as Y, Ti, La or Ce. In one embodiment, the macrostructure is made of an alloy of FeCrAl, which supports a ceramic coating of a mixture of ZrO2 and MgAl2O4, with nickel as the catalytically active material.

[0176] The term "ammonia cracking" is intended to mean the following reaction:

[0177]

[0178] In one embodiment, the endothermic reaction is ammonia cracking. The catalytically active material may be Fe or Ru. The maximum temperature of the reactor may be between 400° C. and 700° C. The pressure of the feed gas may be between 2 bar and 30 bar, preferably about 25 bar.

[0179] The term "hydrogen cyanide synthesis" is intended to mean the following reaction:

[0180]

[0181] In one embodiment, the endothermic reaction is hydrogen cyanide synthesis or organic nitrile synthesis. The catalytically active material may be Pt, Co or SnCo. The maximum temperature of the reactor may be between 700° C. and 1200° C. The pressure of the feed gas may be between 2 bar and 30 bar, preferably about 5 bar.

[0182] In one embodiment, the reactor system also includes a bed of catalyst material (such as catalyst particles) upstream of the structured catalyst within the pressure shell. Here, the term "upstream" is viewed from the flow direction of the feed gas. Therefore, the term "upstream" is intended to mean that the feed gas is directed through the catalyst material bed before reaching the structured catalyst. Such a catalyst bed can perform pretreatment of the feed mixture by, for example, an adiabatic reaction toward a thermal equilibrium of a chemical reaction (such as a water-gas shift). Additionally / alternatively, the catalyst material bed can be used as a protective device to prevent the downstream structured catalyst from being contaminated by impurities (such as sulfur and / or chlorine). No specific heating needs to be provided to the catalyst material bed; however, if the catalyst material bed is in close proximity to the structured catalyst, the catalyst material bed can be heated indirectly.

[0183] In one embodiment, a bed of catalyst material is placed within the pressure housing and downstream of the structured catalyst. This catalyst material may be in the form of catalyst granules, extrudates or particulates. This provides a situation where the fourth catalyst material may be arranged to reduce the equilibrium approach of the gas leaving the structured catalyst by conducting a pseudo-adiabatic equilibrium of the associated reaction.

[0184] It should be understood that the skilled person will readily recognize that any features described in conjunction with the structured catalyst and reactor system for carrying out the endothermic reaction of the feed gas are applicable to this use. Therefore, the above description of the structured catalyst and reactor system is also applicable to its use.

[0185] Detailed description of the drawings

[0186] The same reference numerals refer to the same elements throughout the drawings.

[0187] Figure 1a A cross section of an embodiment of a reactor system 100 according to the present invention is shown. The reactor system 100 includes a structured catalyst 10 arranged into an array of macrostructures 5. Each macrostructure 5 in the array is coated with a ceramic coating impregnated with a catalytically active material. The reactor system 100 also includes conductors 40, 40' connected to a power source (not shown in the figure) and connected to the structured catalyst 10 (i.e., the array of macrostructures). The conductors 40, 40' are guided through the wall of the pressure shell 20 containing the structured catalyst via fittings 50 and are guided through the insulating material 30 on the inner side of the pressure shell. The conductor 40' is connected to the array of macrostructures 5 by a conductor contact rail 41.

[0188] In one embodiment, the power supply supplies a voltage of 26 V and a current of 1200 A. In another embodiment, the power supply supplies a voltage of 5 V and a current of 240 A. The current is led to the conductor contact rail 41 through the electrical conductors 40, 40', and the current is passed through the structured catalyst 10 from a conductor contact rail 41 (e.g., from Figure 1a The conductor contact rail (see left in the figure) flows (runs) to another conductor contact rail 41 (e.g. Figure 1a The current may be either an alternating current and flow, for example, alternately in both directions, or a direct current and flow in either direction.

[0189] The macrostructure 5 is made of a conductive material. Particularly preferred is an alloy Kanthal consisting of aluminum, iron and chromium. The ceramic coating (e.g. oxide) applied on the macrostructure 5 is impregnated with a catalytically active material. The conductors 40, 40' are made of materials such as iron, aluminum, nickel, copper or alloys thereof.

[0190] During operation, feed gas enters the reactor system 100 from above, as indicated by arrow 11. Product gas leaves the reactor system from the bottom of the reactor system, as indicated by arrow 12.

[0191] Figure 1b Shows Figure 1a The reactor system 100 wherein a portion of the pressure shell 20 and the insulating material 30 are removed, and Figure 2 is an enlarged view of a portion of the reactor system 100. Figure 1b and Figure 2 The connection ratio between the conductor 40' and the conductor contact rail 41 is Figure 1a. In addition, it can be seen that the conductor 40 is guided through the wall of the pressure housing in the fitting 50 and that one conductor 40 is divided into three conductors 40' inside the pressure housing. It should be noted that the number of conductors 40' may be any suitable number, such as less than three or even more than three.

[0192] exist Figure 1a , Figure 1b and Figure 2 In the reactor system shown, conductors 40, 40' are guided through the wall of the pressure shell 20 containing the structured catalyst via fittings 50, and are guided through the insulating material 30 on the inside of the pressure shell. As shown by arrow 11, the feed gas for the endothermic reaction enters the reactor system 100 via the inlet on the upper side of the reactor system 100, and as shown by arrow 12, the product gas leaves the reactor system 100 via the outlet at the bottom of the reactor system 100. In addition, one or more additional inlets ( Figure 1a to Figure 2 The inlet (not shown) is advantageously located near the fitting 50 or in combination with the fitting 50. Such an additional inlet allows a cooling gas to flow over, around, near or inside at least one conductor in the pressure shell to reduce heating of the fitting. The cooling gas may be, for example, hydrogen, nitrogen, methane or a mixture thereof. The temperature of the cooling gas entering the pressure shell may be, for example, about 100°C.

[0193] exist Figure 1a to Figure 2 In the reactor system 100 shown, the inert material ( Figure 1a to Figure 2 The inert material (not shown) is advantageously present between the lower side of the structured catalyst 10 and the bottom of the pressure shell. In addition, an inert material is advantageously present between the outer side of the structured catalyst 10 of the macrostructure 5 and the insulating material 30. Thus, one side of the insulating material 30 faces the inner side of the pressure shell 20, and the other side of the insulating material 30 faces the inert material. The inert material is, for example, a ceramic material, and may be in the form of particles. The inert material helps control the pressure drop across the reactor system 100 and helps control the flow of gas through the reactor system 100, so that the gas flows on the surface of the structured catalyst 10.

[0194] Figure 3a-3f Six different mesh structures 6 are shown, of which only a portion of the mesh structure 6 is shown. The macrostructure 5 includes a three-dimensional mesh structure 6, wherein the mesh structure 6 forms a structure that allows the feed gas to flow from the first end 14 of the macrostructure 5 (see Figure 5 ) flows to the second end 15 (see Figure 5 ). The mesh structure 6 is formed of a metallic material that is electrically conductive and at least partially supports a ceramic coating, wherein the ceramic coating supports the catalytically active material. The six different portions of the mesh structure 6 each include a different embodiment of a cutout 60 in the mesh structure.

[0195] The current distribution in a component is governed by Ohm's law, which for a simple conductor with DC current is defined as:

[0196] U=R·I

[0197] Where U is the potential [V], R is the resistance [Ω], and I is the current [A]. For three-dimensional geometries, this can be written as:

[0198] E=ρ res ·J

[0199] where E is the electric field vector [V / m], ρ res is the resistivity [Ω·m], J is the current density vector [A / m 2 ]. The resistance R is inherently dependent on the geometry, where the resistivity is a material-specific parameter derived from the cross-sectional resistance per length.

[0200]

[0201] Thermal resistance losses are defined as the product of the current and the potential drop across the component, which can be rewritten based on Ohm's law, depending on potential or current control.

[0202]

[0203] Since the resistance R is a geometry-dependent parameter, the power supplied to the area can be adjusted by varying the cross-sectional area.

[0204] Figure 3a-3f Six different ways of varying the cross section of the mesh structure 6 by means of six different examples of cutouts 60 are shown. Figure 3a A cutout 60 in the form of a sphere is shown, Figure 3b A disc-shaped cutout 60 is shown, Figure 3c An oval cutout 60 is shown, Figure 3d A droplet cutout 60 is shown, Figure 3e A diamond-shaped cutout 60 is shown, Figure 3f Diamond shaped cutouts 60 are shown.

[0205] The cutouts 60 are filled with a cutout material having a lower electrical conductivity than the metallic material forming the mesh structure 6. The cutout material may be void (ie, empty) or may be solid cutout material.

[0206] Figure 4a-4b Different embodiments of the cutouts 60 of the mesh structure 6 are shown. Only a portion of the mesh structure 6 is shown. Figure 4a In the embodiment, the cutout 60 is formed in a single plane of the mesh structure 6, and Figure 4bThe cutout 60 shown in FIG. 1 intersects two planes, and Figure 4c The cutout 60 shown in FIG. 6 intersects three planes.

[0207] The mesh structure 6 constitutes a sub-portion of the cross section of the macrostructure 5 in a cross section transverse to the longitudinal direction. The sub-portion is in the range of 4%-75%. The mesh structure constitutes at least three different cross sections along the longitudinal direction, constituting different sub-portions.

[0208] The following figures illustrate different embodiments of macrostructures 5 with different mesh structures 6. The geometry of each embodiment is shown in a separate figure; i.e., Figure 5 , Figure 7 , Fig. 9 , Fig.11 and Fig.13 .

[0209] The mesh structure 6 constitutes a subsection of the cross section of the macrostructure 5 in a cross section transverse to the longitudinal direction. For each embodiment, the subsection is respectively Figure 6a , Figure 8a , Fig.10a , Fig.12a and Fig.14a In these figures, the subsections are designated as relative metal cross sections.

[0210] For each example, Figure 6b , Figure 8b , Fig.10b , Figure 12b and Fig.14b The relative change in cross-sectional area of ​​the mesh per unit length is shown, where the unit is a single macrostructure. The cross section roughly resembles the current density distribution defined by Ohm's law. For some structures, this is additionally shown in separate figures for Comsol simulations; see Figure 6c , Figure 8c , Fig.10c , Fig.12c and Fig.14c .

[0211] Figure 5 An embodiment of a macrostructure 5 is shown in which a mesh structure 6 includes a plurality of cutouts 60. The cutouts 60 are all spherical and filled with solid cutout material. The cutouts 60 intersect with an inner wall 61 of the mesh structure 6. The inner wall 61 forms a plurality of flow channels 62 from the first end 14 to the second end 15. In the embodiment shown, the mesh structure forms a plurality of parallel flow channels 62. The plurality of inner walls 61 are arranged in an inner space formed by a circumferential wall 63. In the embodiment shown, the circumferential wall does not include a cutout.

[0212] The resistance of the macrostructure 5 shown is 220% compared to a macrostructure with parallel flow channels but without the spherical cutouts 60. Calculations show that 51% of the total volume of the macrostructure exceeds 5% of the average current density, while 32% of the total volume of the macrostructure is below the average current density. At the point with the peak current, the current density exceeds the total average by 173%.

[0213] Figure 6a Shows Figure 5 1 shows a relative metal cross section of an embodiment of the macrostructure 5 shown in FIG. As shown, for this embodiment, the subsection is in the range of 17%-30%, with all possible values ​​in this range due to the continuous nature of the curve. Along the structure, the subsection has a continuous non-constant behavior in the longitudinal direction for more than 90%.

[0214] Figure 6b Shows Figure 5 The relative variation of cross-sectional area per unit length of the embodiment of the macrostructure 5 shown in FIG. As shown, within 1 mm of the length of the macrostructure 5, the cross-sectional area can vary by up to 80%.

[0215] Figure 6c The current density of the macrostructure 5 simulated by Comsol software is shown. This shows how the cutouts 60 force the current density to increase in the remainder of the mesh structure 6. The scale of the graph is a relative scale from 1 to 0, using the peak current as normalization.

[0216] Figure 7 An embodiment of a macrostructure 5 is shown, in which the mesh structure 6 comprises a plurality of cutouts 60. The cutouts 60 are all circular channels positioned perpendicular to the longitudinal direction of the macrostructure. In this embodiment, the cutouts 60 are voids. During use, the cutouts (voids) 60 (empty cutouts) will be filled with gas flowing through the macrostructure 5. The cutouts 60 intersect with the inner wall 61 of the mesh structure 6. The cutouts 60 are arranged alternately in rows with two channels and rows with three channels, respectively.

[0217] The resistance of the macrostructure 7 shown is 142% compared to a macrostructure with parallel flow channels but without cutouts 60. Calculations show that 46% of the total volume of the macrostructure exceeds 5% of the average current density, while 30% of the total volume of the macrostructure is below the average current density. At the point with peak current, the current density exceeds the total average by 109%.

[0218] The inner wall 61 forms a plurality of flow channels 62 from the first end 14 to the second end 15. In the illustrated embodiment, the mesh structure forms a plurality of parallel flow channels 62. The plurality of inner walls 61 are arranged in an inner space formed by the circumferential wall 63. In the illustrated embodiment, the circumferential wall 63 also includes a cutout 60, because the flow channels 62 extend from one side of the macrostructure 5 to the opposite side.

[0219] Figure 8a Shows Figure 7 . As shown, for this embodiment, the sub-portion is in the range of 17%-30%. Along the structure, the sub-portion has a continuous non-constant behavior in the longitudinal direction for more than 60%.

[0220] Figure 8b Shows Figure 7 The relative variation of cross-sectional area per unit length of the embodiment of the macrostructure 5 shown in FIG. As shown, within 1 mm of the length of the macrostructure 5, the cross-sectional area can vary by up to 60%.

[0221] Figure 8c The current density of the macrostructure 5 simulated by Comsol software is shown. This shows how the cutouts 60 force the current density to increase in the remainder of the mesh structure 6. The scale of the graph is a relative scale from 1 to 0, using the peak current as normalization.

[0222] Fig. 9 An embodiment of a macrostructure 5 is shown in which the mesh structure 6 includes a plurality of cutouts 60. The cutouts 60 are all circular channels positioned perpendicular to the longitudinal direction of the macrostructure. In this embodiment, the cutouts 60 are gaps. The cutouts 60 intersect the inner wall 61 of the mesh structure 6. This embodiment is similar to Figure 7 The embodiment of the present invention is different in that the cutouts 60 in this embodiment are all arranged in rows, each row having two channels.

[0223] The resistance of the macrostructure 9 shown is 125% compared to a macrostructure with parallel flow channels but without cutouts 60. Calculations show that 63% of the total volume of the macrostructure exceeds 5% of the average current density, while 23% of the total volume of the macrostructure is below the average current density. At the point with peak current, the current density exceeds the total average by 96%.

[0224] The inner wall 61 forms a plurality of flow channels 62 from the first end 14 to the second end 15. In the illustrated embodiment, the mesh structure forms a plurality of parallel flow channels 62. The plurality of inner walls 61 are arranged in an inner space formed by the circumferential wall 63. In the illustrated embodiment, the circumferential wall 63 also includes a cutout 60, because the flow channels 62 extend from one side of the macrostructure 5 to the opposite side.

[0225] Fig.10a Shows Fig. 9 1 shows a relative metal cross section of an embodiment of a macrostructure 5 shown in FIG. As shown, for this embodiment, the sub-portion is in the range of 21%-30%.

[0226] Fig.10b Shows Fig. 9 Relative variation of cross-sectional area per unit length for the illustrated embodiments of the macrostructure 5. As shown, within 1 mm of the length of the macrostructure 5, the cross-sectional area can vary by up to 20%.

[0227] Fig.10c The current density of the macrostructure 5 simulated by Comsol software is shown. This shows how the cutouts 60 force the current density to increase in the remainder of the mesh structure 6. The scale of the graph is a relative scale from 1 to 0, using the peak current as normalization.

[0228] Fig.11 An embodiment of a macrostructure 5 is shown in which the mesh structure 6 is formed as a grid.

[0229] The resistance of the macrostructure 11 shown is 304% compared to a macrostructure with parallel flow channels but without cutouts 60. Calculations show that 71% of the total volume of the macrostructure exceeds 5% of the average current density, while 24% of the total volume of the macrostructure is below the average current density. At the point with peak current, the current density exceeds the total average by 389%.

[0230] The mesh structure (grid) 6 forms a plurality of flow channels 62 from the first end 14 to the second end 15. The mesh structure (grid) 6 is arranged in an inner space formed by a circumferential wall 63. For illustration purposes, a portion of the circumferential wall 63 has been removed.

[0231] Fig.12a Shows Fig.11 1. Relative metal cross-section of an embodiment of macrostructure 5 shown in FIG. As shown, for this embodiment, the sub-portion is in the range of 10.5%-16%.

[0232] Figure 12b Shows Fig.11 The relative variation of cross-sectional area per unit length of the embodiment of the macrostructure 5 shown in FIG. As shown, within 1 mm of the length of the macrostructure 5, the cross-sectional area can vary by up to 25%.

[0233] Fig.12c The current density of the macrostructure 5 simulated by Comsol software is shown. This shows how the cutouts 60 force the current density to increase in the remainder of the mesh structure 6. The scale of the graph is a relative scale from 1 to 0, using the peak current as normalization.

[0234] Fig.13 An embodiment of a macrostructure 5 is shown in which the mesh structure 6 is formed as a grid. The mesh structure (grid) 6 forms a plurality of flow channels from a first end 14 to a second end 15. The mesh structure (grid) 6 is attached to a manifold 65 at the first end 14 and at the second end 15. In this embodiment, the macrostructure 5 does not include a circumferential wall.

[0235] The resistance of the macrostructure 13 shown is 1087% compared to a macrostructure with parallel flow channels but without cutouts 60. Calculations show that 36% of the total volume of the macrostructure exceeds 5% of the average current density, while 55% of the total volume of the macrostructure is below the average current density. At the point with peak current, the current density exceeds the total average by 791%.

[0236] Fig.14a Shows Fig.13 1 shows a relative metal cross section of an embodiment of a macrostructure 5 shown in FIG. As shown, for this embodiment, the sub-portion is in the range of 4%-75%.

[0237] Fig.14b Shows Fig.13 Relative variation of cross-sectional area per unit length of the illustrated embodiment of the macrostructure 5. As shown, the cross-sectional area can vary by up to 50% within 1 mm over the length of the mesh 6. The variation from the interface between the mesh 6 and the manifold 65 at the first end 14 to the interface between the mesh 6 and the manifold 65 at the second end 15 is over 100% / mm.

[0238] Fig.14c The current density of the macrostructure 5 simulated by Comsol software is shown. This shows how the mesh formed by the grid 6 forces the current density to increase in the rest of the mesh 6. The scale of the figure is a relative scale from 1 to 0, using the peak current as normalization.

[0239] Fig.15 Compared with a macrostructure with parallel flow channels but without a mesh structure with sub-section variation, Figure 5 , Figure 7 , Fig. 9 , Fig.11 and Fig.13 The relative resistance increase of the examples presented in . It is clear that an increased resistance from +25% to +1000% is achieved using the method of the invention. The resistance is simulated using Comsol. During the simulation, a resistivity of 134 μΩ*cm was used (corresponding to the use of Kanthal).

[0240] Fig.16a and Fig.16bDifferent views of an embodiment of a structured catalyst 10 comprising two macrostructures 5 are shown, each macrostructure comprising a mesh structure 6 forming a plurality of inner walls 61 .

[0241] The inner wall 61 forms a plurality of flow channels 62 from the first end 14 to the second end 15 . Fig.16a The channel is shown from above (from the first end 14 ), whereas FIG. 16 shows the channel from below (from the second end 15 ).

[0242] In the illustrated embodiment, the macrostructures 5 are connected to each other at the second ends 15 without using a separate bridge to connect the two macrostructures 5 because the macrostructures 5 are integrally formed with each other at the second ends 15. Fig.16b As shown, the inner wall is thicker at the second end than at the first end. These thicker walls are actively cooled by the airflow on both sides in the flow channel 62.

[0243] Fig.17 An embodiment of a structured catalyst 10 is shown comprising two macrostructures 5, each macrostructure comprising a mesh structure 6 forming a plurality of inner walls 61. The inner walls 61 form a plurality of flow channels 62 from a first end 14 to a second end 15.

[0244] In the embodiment shown, the macrostructures 5 are connected to each other at the second end 15 by using a plurality of individual bridges 66 , which connect the left side of one macrostructure 5 to the right side of an adjacent macrostructure 5 .

[0245] In the illustrated embodiment, the flow channels 62 are substantially parallel in some sections along the longitudinal direction, while the direction and / or cross-sectional area of ​​at least some of the flow channels 62 vary in the longitudinal direction in other sections. As seen at the top of the macrostructure 5, the wall thickness of some flow channels is thicker than the wall thickness of other flow channels, thereby providing a macrostructure 5 with inner walls of uneven wall thickness. The cross-sectional area of ​​the macrostructure can also vary along the longitudinal direction by modifying the direction and / or cross-sectional area of ​​at least some of the inner walls 61. The height of different sections along the longitudinal direction can also vary.

[0246] Figure 18a-Figure 18c Shown through Fig.17 Different cross sections of the embodiment shown in . Fig.18a A cross section through the structured catalyst is shown at the upper section in the region of the first end 14. The thicker wall 61 can ensure a better current distribution through this section of the macrostructure 5. Fig.18b A cross section through the structured catalyst at the middle section is shown. The uniform wall thickness of the wall 61 in this section can ensure uniform heating in this section of the macrostructure 5. Fig.18cA cross section through the structured catalyst is shown at the lower section in the region of the second end 15. The thicker wall 61 can ensure a better current distribution through this section of the macrostructure 5.

[0247] Fig.18d Shows Fig.17 Relative metal cross-section of the embodiment shown in . As shown, for this embodiment, the sub-portion is in the range of 42%-100%.

[0248] exist Figure 19a-Figure 22b In each of the structured catalysts 10, a first macrostructure 5A and a second macrostructure 5B are included, each macrostructure extending in a longitudinal direction from a first end 14 to a second end 15, wherein the first end 14 forms an inlet of the macrostructure 10 for a feed gas, and wherein the second end 15 forms an outlet for a product gas.

[0249] The first macrostructure 5A and the second macrostructure 5B include a three-dimensional network structure (see Fig.19a ), wherein the mesh structure forms a flow path that allows the feed gas to flow from the first end 14 to the second end 15. Fig.19a As shown in the left portion of FIG, at least a portion of the mesh structure forms a plurality of parallel flow channels 62. However, it should be understood that at least some of the channels may not be parallel.

[0250] The flow channel 62 is only Fig.19a The left side of Fig.19a - In the remainder of Figure 33b, openings of the mesh structure, such as flow channels, cutouts, slits, etc., are omitted.

[0251] The second macrostructure 5B is arranged to circumferentially surround the first macrostructure 5A, and the first macrostructure 5A and the second macrostructure 5B are electrically connected at the second end 15. The structured catalyst 10 is configured to guide the current to flow through the first macrostructure 5A from the first end 14 to the second end 15, and then flow through the second macrostructure 5B from the second end 15 to the first end 14 by electrically connecting the first macrostructure 5A and the second macrostructure 5B at the second end 15.

[0252] In the illustrated embodiment, the second macrostructure 5B is an elongated structure extending in the longitudinal direction from the first end 14 to the second end 15. The second macrostructure 5B is hollow so as to completely surround the first macrostructure 5A, whereby the inner surface of the second macrostructure 5B faces the outer surface of the first macrostructure 5A.

[0253] It will be appreciated that in alternative embodiments (not shown), the second macrostructure may be arranged partially circumferentially around the first macrostructure, whereby a portion of the inner surface of the second macrostructure faces a portion of the outer surface of the first macrostructure.

[0254] The first macrostructures 5A and the second macrostructures 5B at least partially support a ceramic coating which supports the catalytically active material.

[0255] exist Fig.19a In the embodiment, the structured catalyst 10 includes a first macrostructure 5A and a second macrostructure 5B, each of which extends in the longitudinal direction from a first end 14 to a second end 15. The first macrostructure 5A and the second macrostructure 5B both form a circular shape in a cross section perpendicular to the longitudinal direction.

[0256] Fig.19b Shown through Fig.19a A cross section of the embodiment of the structured catalyst 10 is shown. The flow channel 62 is clearly shown in the cross section on the left. Furthermore, the cross section clearly shows that the first macrostructure 5A and the second macrostructure 5B are connected at the second end 15.

[0257] exist Fig. 20 , the structured catalyst 10 includes a first macrostructure 5A and a second macrostructure 5B, each of which extends from a first end 14 to a second end 15 in the longitudinal direction. The first macrostructure 5A and the second macrostructure 5B both form a square shape in a cross section perpendicular to the longitudinal direction. In the cross section on the right, it is clearly shown that the first macrostructure 5A and the second macrostructure 5B are connected at the second end 15.

[0258] exist Fig.21 , the structured catalyst 10 includes a first macrostructure 5A and a second macrostructure 5B, each of which extends from a first end 14 to a second end 15 in the longitudinal direction. The first macrostructure 5A and the second macrostructure 5B both form an organic outer shape in a cross section perpendicular to the longitudinal direction. In the cross section on the right, it is clearly shown that the first macrostructure 5A and the second macrostructure 5B are connected at the second end 15.

[0259] Fig.22a Two different embodiments of the structured catalyst 10 are shown, each including a first macrostructure 5A and a second macrostructure 5B, each of which extends in the longitudinal direction from a first end 14 to a second end 15. The first macrostructure 5A and the second macrostructure 5B on the left both form a hexagonal shape in a cross section perpendicular to the longitudinal direction, while the first macrostructure 5A and the second macrostructure 5B on the right both form a triangular shape in a cross section perpendicular to the longitudinal direction.

[0260] Figure 22b Shown through Fig.22aThe cross section clearly shows that the first macrostructure 5A and the second macrostructure 5B are connected at the second end 15.

[0261] Fig.23a An embodiment of a macrostructure 5 is shown in which the mesh structure 6 is formed as a grid. The mesh structure (grid) 6 forms a plurality of flow channels from a first end 14 to a second end 15. The mesh structure (grid) 6 is attached to a manifold 65 at the first end 14 and at the second end 15. In this embodiment, the macrostructure 5 does not include a circumferential wall. The embodiment shown is similar to Fig.13 The embodiment shown in , has a denser mesh structure (grid) 6.

[0262] Figure 23b An embodiment of a structured catalyst 10 is shown, which includes two macrostructures 5 connected at a first end 14 to form a U-shaped structured catalyst 10. The mesh structure 6 of each macrostructure 5 is formed as a grid. The mesh structure (grid) 6 forms a plurality of flow channels from the first end 14 to the second end 15. The radial and axial dimensions of the mesh structure 6 vary along the longitudinal direction of the structured catalyst 10. In the middle portion of each macrostructure 5, the mesh structure (grid) 6 is similar to Fig.23a The mesh of the illustrated embodiment. By changing the mesh structure 6 in the axial direction and the radial direction, the current in the mesh structure 6 can be effectively controlled.

[0263] Fig.24 An embodiment of a structured catalyst 10 is shown, which includes two macrostructures 5 connected at the second end 15 by an integrally formed bridge portion 66. The macrostructures 5 each include a mesh structure 6 forming a plurality of inner walls 61. The inner walls 61 form a plurality of substantially parallel flow channels 62 from the first end 14 to the second end 15. The flow channels 62 are arranged in an inner space formed by a circumferential wall 63.

[0264] The circumferential wall 63 does not extend to the bottom of the macrostructure 5, minimizing the current density at the second end (bottom end) and promoting its cooling. At the first end (upper end), the structured catalyst 10 comprises two conductors 40 that can be connected to an electric power source.

[0265] Fig.25 An embodiment of a macrostructure 5 and a plurality of arrays of macrostructures 5 is shown. Each macrostructure 5 extends from a first end 14 to a second end 15. The macrostructures 5 each include a mesh structure 6 forming a plurality of inner walls 61. The inner walls 61 form a plurality of substantially parallel flow channels 62 from the first end 14 to the second end 15. The flow channels 62 are arranged in an inner space formed by a circumferential wall 63.

[0266] In the first embodiment, a single macrostructure 5 is shown from the left.

[0267] In the second embodiment, two macrostructures 5 are connected to each other at the second ends 15 , whereby current can flow from the first end 14 to the second end 15 of one macrostructure 5 and then from the second end 15 to the first end 14 of the other macrostructure 5 .

[0268] In a third embodiment, the array comprises four macrostructures 5, similar to Fig.25 The second macrostructure 5 is connected to the third macrostructure 5 at the first end 14 , and the third macrostructure 5 is connected to the fourth macrostructure 5 at the second end 15 .

[0269] In the fourth embodiment, the array comprises a plurality of macrostructures 5 arranged in a block configuration. Some macrostructures 5 are connected to adjacent macrostructures 5 at a first end 14, and some macrostructures 5 are connected to adjacent macrostructures 5 at a second end 15. The fourth embodiment further comprises a plurality of cutouts 60 in the form of slits.

[0270] In all four embodiments, the air flow is in a longitudinal direction from the first end 14 to the second end 15 .

[0271] Fig.26 Different embodiments of a structured catalyst 10 are shown. The structured catalyst 10 comprises a macrostructure 5 in the form of a plurality of plate-like elements 5' forming a mesh-like structure 6 forming a plurality of inner walls 61. The inner walls 61 form a plurality of flow channels 62 from a first end 14 to a second end 15.

[0272] In the above embodiment, the plate-like elements 5' are all connected to rod-like conductive elements 67, which are connected to conductive elements 67 extending out of the interior space, thereby allowing connection to adjacent structured catalysts to form an array.

[0273] In the two lower embodiments, the macrostructure 5 is in the form of a plate-like element 5 ′ which is bent so as to form a plurality of inner walls 61 .

[0274] In the lower left embodiment, the plate-like element 5' is connected to a rod-like conductive element 67 extending out of the interior space through the bottom, thereby allowing connection to the structured catalyst to form an array. In the lower right embodiment, the plate-like element 5' is connected to a rod-like conductive element 67 extending out of the interior space in a direction transverse to the longitudinal direction, thereby allowing connection to adjacent structured catalysts to form an array.

[0275] One or more cutouts (such as slits and / or through holes in various forms) may be formed in the plate-like element (see Fig.28 ).

[0276] Fig. 27 An embodiment of a structured catalyst 10 is shown. The structured catalyst 10 is similar to Fig.26 The embodiment shown in FIG. 1 comprises a macrostructure 5 in the form of a plurality of plate-like elements 5'. One or more cutouts may be formed in the plate-like elements (see Fig.28 ).

[0277] The curved plate-like element 5' comprises notches 68 at opposite edges to facilitate mounting of the structured catalyst 10 in a reactor (see for example Figure 1a )middle.

[0278] Fig.28 Different plate-like elements 5' are shown, which can be used as macrostructures 5 or parts of macrostructures in the structured catalyst according to the present disclosure. The plate-like element 5' can be arranged as a plate extending substantially from a first end to a second end (see e.g. Fig.26 Alternatively, the plate-like element 5' may be curved, wherein the curved element may extend substantially from a first end to a second end (see for example Fig.26 The following examples shown in Fig. 27 ).

[0279] As shown, the plate-like element 5' may include one or more cutouts 60, such as slits and / or through holes of different forms. In the above embodiment, the cutouts are arranged as small through holes to form a fine grid. In a second embodiment, the cutouts are formed as two identical rows of diamond-shaped through holes. In a third embodiment, the cutouts are formed as slits extending alternately from opposite edges of the plate-like element 5', wherein the slits terminate at circular through holes. In a fourth embodiment, the cutouts are formed as two rows of elongated through holes, wherein the lengths of the through holes are different because the first row includes longer through holes than the second row. In a fifth embodiment, the cutouts are arranged as circular through holes of the same size. The cutouts are arranged in two substantially parallel rows and in a zigzag pattern.

[0280] It will be appreciated that the size and shape of the cutouts may vary and that the illustrated embodiments are examples. The different cutouts illustrated in the five different embodiments may be combined to form a plate-like element 5' with alternative forms of cutouts, for example diamond-shaped cutouts may be combined with slits and / or circular cutouts.

[0281] In addition, it should be understood that Fig.26 The above embodiment may, as an example, comprise an identical plurality of plate-like elements 5 ′ or a plurality of plate-like elements of which at least two are different.

[0282] Fig.29a and Fig.29bDifferent plate-like elements 5' are shown, which can be used as macrostructures 5 or parts of macrostructures in the structured catalyst according to the present disclosure. The plate-like element 5' may include cutouts, for example, Fig.28 shown.

[0283] Fig.29a A cross section transverse to the longitudinal direction of the coiled plate-like element 5' is shown.The plate-like element 5' is connected to a rod-like conducting element 67, allowing connection to a power supply.

[0284] Fig.29b A cross section along the longitudinal direction of a corrugated plate-like element 5' is shown. In the upper embodiment, the angle of the corrugations is more acute than in the middle embodiment. The lower embodiment is similar to the middle embodiment, with the addition of a planar element attached to the corrugated element.

[0285] As an example, these corrugated elements 5' can be used in Fig.26 and Fig. 27 It should also be understood that Fig.29a The coiled element 5' in the embodiment may also be corrugated; that is, Fig.29a The embodiment shown in Fig.29b By corrugating the coiled element 5', the conductive material can be formed into a larger cross-sectional area.

[0286] Fig.30a An inner wall 61 is shown as being a part of the macrostructure 5. The inner wall 61 comprises a plurality of cutouts 60 in the form of slits extending from opposite edges and a plurality of circular through holes, wherein the cutouts 60 constitute 4% - 75% of the cross-sectional area of ​​the inner wall.

[0287] Fig.30b It shows that Fig.30a Four inner walls 61 are shown, wherein the inner walls 61 are attached to a circumferential wall 63. The inner walls 61 form a plurality of substantially parallel flow channels 62 from the first end 14 to the second end 15. The flow channels 62 are arranged in the inner space formed by the circumferential wall 63. At least three of the inner walls 61 have different cross-sectional areas.

[0288] The following numbered entries are provided:

[0289] Item 1. A structured catalyst for catalyzing an endothermic reaction of a feed gas to convert it into a product gas, the structured catalyst comprising at least one macrostructure extending from a first end to a second end in a longitudinal direction, wherein the first end forms an inlet of the macrostructure for the feed gas and the second end forms an outlet for the product gas, the macrostructure comprising a three-dimensional mesh structure, wherein the mesh structure forms a flow path allowing the feed gas to flow from the first end to the second end, wherein the mesh structure is formed of a conductive metal material and at least partially supports a ceramic coating, the ceramic coating supporting a catalytically active material, wherein the mesh structure constitutes a sub-portion of a cross-section of the macrostructure in a cross-section transverse to the longitudinal direction, the sub-portion being in the range of 4%-75%, and wherein the mesh structures in at least three different cross-sections along the longitudinal direction constitute different sub-portions.

[0290] Item 2. The structured catalyst according to Item 1, wherein the macrostructure further comprises a circumferential wall forming an inner space, the circumferential wall being formed of a conductive metal material, and wherein the mesh structure is arranged in the inner space.

[0291] Item 3. The structured catalyst according to Item 1, wherein the macrostructure further comprises a circumferential wall forming an inner space, the circumferential wall being formed of a non-conductive material, and wherein the mesh structure is arranged in the inner space.

[0292] Item 4. A catalyst according to any of the preceding items, wherein the cross-section of the mesh structure in the longitudinal direction constitutes at least 4, preferably 5, more preferably 6, more preferably 7, more preferably 8, more preferably 9, more preferably 10, more preferably 11, and most preferably 12 sub-parts.

[0293] Item 5. A catalyst according to any of the preceding items, wherein the cross-section of the network structure is continuous and non-constant in the longitudinal direction over a combined distance of at least 10%, preferably 20%, more preferably 30%, more preferably 40%, more preferably 50%, more preferably 60%, more preferably 70%, more preferably 80%, and most preferably 90% of the length of the macrostructure.

[0294] Item 6. A catalyst according to any of the preceding items, wherein the cross-section of the network structure is continuous and non-constant in a direction transverse to the longitudinal direction over a combined distance of at least 10%, preferably 20%, more preferably 30%, more preferably 40%, more preferably 50%, more preferably 60%, more preferably 70%, more preferably 80%, and most preferably 90% of the length of the macrostructure.

[0295] Item 7. The catalyst according to any of the preceding items, wherein the mesh structure comprises a plurality of cutouts.

[0296] Item 8. The catalyst according to Item 7, wherein the cutouts are filled with a cutout material having a lower electrical conductivity than the metal material.

[0297] Item 9. The catalyst according to Item 7 or 8, wherein the incision material is a solid material.

[0298] Item 10. The structured catalyst according to Item 9, wherein the solid material has thermomechanical properties substantially equivalent to those of the metal material forming the network structure.

[0299] Item 11. The catalyst of Item 7, wherein a first subset of the cutouts is filled with air, and wherein a second subset of the cutouts is filled with a solid material.

[0300] Item 12. The catalyst according to any of the preceding items, wherein at least a portion of the network structure forms a plurality of parallel flow channels.

[0301] Item 13. A structured catalyst according to any of the preceding items, wherein the variation of the sub-portions along the longitudinal direction is less than 500% / mm, preferably less than 100% / mm, even more preferably less than 50% / mm.

[0302] Item 14. A structured catalyst according to any of the preceding items, wherein the macrostructure(s) are produced by 3D printing.

[0303] Item 15. The structured catalyst according to any one of items 1 to 3, wherein the macrostructure(s) are produced by bending, cutting and / or welding metal sheets.

[0304] Item 16. The structured catalyst according to any one of Items 2 to 15, wherein the circumferential wall does not include openings transverse to the longitudinal direction.

[0305] Item 17. The structured catalyst according to any of the preceding items, comprising two or more macrostructures, wherein at least two macrostructures are electrically connected.

[0306] Item 18. A structured catalyst according to any of the preceding items, wherein two adjacent macrostructures are made into a single piece by 3D printing to form an electrical connection between the two macrostructures closest to the first end or the second end of the macrostructures.

[0307] Item 19. The structured catalyst of any of Items 17-18, wherein the second macrostructure is arranged to at least partially circumferentially surround the first macrostructure.

[0308] Item 20. The structured catalyst of Item 19, wherein the first macrostructure and the second macrostructure are electrically connected at the second end.

[0309] Item 21. The structured catalyst according to any one of Items 19-20, wherein the outer surface of the first macrostructure has a shape that matches the inner surface of the second macrostructure.

[0310] Item 22. The structured catalyst of Item 21, wherein the outer surface of the first macrostructure is substantially circular in a cross-section transverse to the longitudinal direction.

[0311] Item 23. The structured catalyst according to any one of Items 19 to 22, wherein the first macrostructure and the second macrostructure are arranged substantially coaxially.

[0312] Item 24. A structured catalyst according to any of the preceding items, wherein at least one macrostructure comprises flow guides to ensure flow distribution, wherein these flow guides are 3D printed integrally with the macrostructure.

[0313] Item 25. A structured catalyst according to any of the preceding items, wherein at least one macrostructure comprises an attachment section to allow direct attachment of an electrical connection, wherein the attachment section is 3D printed integrally with the macrostructure.

[0314] Item 26. The structured catalyst according to any of the preceding items, comprising at least two macrostructures, wherein the two macrostructures comprise parallel outer sections to enable geometrical engagement in the longitudinal direction or in a direction transverse to the longitudinal direction.

[0315] Item 27. The structured catalyst according to Item 26, wherein the two macrostructures are held together by welding, soldering or mechanical pressing.

[0316] Item 28. The structured catalyst according to any one of Items 7 to 27, wherein at least one of the cutouts has a shape selected from the group consisting of a sphere, a disk, an ellipsoid, a droplet, a spiral, and a polyhedron such as a box, a pyramid, a diamond, and a rhombus.

[0317] Item 29. The structured catalyst according to any one of Items 7 to 28, wherein at least two of the cutouts have different forms and / or shapes.

[0318] Item 30. A structured catalyst according to any one of items 2 to 29, comprising at least two macrostructures, wherein the thickness of the circumferential wall in the section providing electrical connection to the second macrostructure is 25%, preferably 50%, even more preferably 100%, even more preferably 200% higher than the average thickness of the circumferential wall.

[0319] Item 31. A structured catalyst according to any of the preceding items, wherein the metal material is an alloy comprising one or more substances selected from the group consisting of Fe, Cr, Al, Co, Ni, Zr, Cu, Ti, Mn and Si.

[0320] Item 32. The structured catalyst according to any of the preceding items, wherein the catalyst comprises one or more arrays, each of the one or more arrays comprising a first macrostructure and a second macrostructure, wherein:

[0321] a) the first macrostructure and the second macrostructure include a three-dimensional network structure;

[0322] b) the array comprises at least a first conductor and a second conductor, the first conductor and the second conductor being electrically connected to the first macrostructure and the second macrostructure, respectively, and to a power source, wherein the power source is dimensioned to heat at least a portion of the first macrostructure and the second macrostructure to a temperature of at least 500° C. by passing an electric current through the macrostructures, and wherein the conductors are connected to the macrostructures at a location closer to the first end than to the second end,

[0323] c) the first macrostructure and the second macrostructure are electrically connected via a bridge of conductive material, and

[0324] d) The array is configured to direct current from the first conductor through the first macrostructure to the second end, then across the bridge, and then through the second macrostructure to the second conductor.

[0325] Item 33. The structured catalyst of Item 32, wherein the second conductor is indirectly electrically connected to the second macrostructure.

[0326] Item 34. A structured catalyst according to Item 33, wherein the array further comprises: (i) one or more juxtaposed additional intermediate macrostructures; and (ii) an end macrostructure, wherein each additional intermediate macrostructure is connected to at least two juxtaposed macrostructures by a bridge of conductive material, and wherein the end macrostructure is connected to at least one juxtaposed macrostructure, and wherein a second conductor is connected to the end macrostructure at a position on the end macrostructure that is closer to the first end than to the second end.

[0327] Item 35. The structured catalyst according to any one of Items 32 to 34, wherein at least two juxtaposed macrostructures have different progressions of sub-portions along their longitudinal direction.

[0328] Item 36. A reactor system for performing an endothermic reaction of a feed gas, the reactor system comprising:

[0329] a) The structured catalyst according to any one of items 1 to 35;

[0330] b) a pressure housing containing the structured catalyst, the pressure housing comprising an inlet for admitting the feed gas and an outlet for admitting the product gas, wherein the inlet is positioned such that the feed gas enters the structured catalyst at a first end and the product gas exits the catalyst from a second end; and

[0331] c) A thermal insulation layer between the structured catalyst and the pressure housing.

[0332] Item 37. Use of the structured catalyst according to any one of items 1 to 35 or the reactor according to item 36, wherein the endothermic reaction is selected from the group consisting of steam methane reforming, hydrogen cyanide formation, methanol cracking, ammonia cracking, reverse water gas shift and dehydrogenation.

Claims

1. A structured catalyst for catalyzing an endothermic reaction of a feed gas to convert it into a product gas, the structured catalyst comprising at least one macrostructure extending from a first end to a second end in a longitudinal direction, wherein the first end forms an inlet of the macrostructure for the feed gas and the second end forms an outlet for the product gas, the macrostructure comprising a three-dimensional network structure, wherein, The mesh structure forms a flow path allowing the feed gas to flow from the first end to the second end, wherein the mesh structure is formed of a conductive metal material and at least partially supports a ceramic coating, which supports a catalytically active material, wherein the mesh structure constitutes a sub-portion of the cross-section of the macrostructure in a cross-section transverse to the longitudinal direction, the sub-portion being in the range of 4%-75%, and wherein the mesh structure in at least three different cross-sections along the longitudinal direction constitutes different sub-portions.

2. The structured catalyst according to claim 1, wherein The macrostructure further comprises a circumferential wall forming an inner space, the circumferential wall being formed of an electrically conductive metallic material, and wherein the mesh structure is arranged in the inner space.

3. The catalyst according to claim 1 or 2, wherein The cross section of the mesh structure comprises at least four sub-divisions along the longitudinal direction.

4. The catalyst according to claim 1 or 2, wherein The cross-section of the network structure is continuously non-constant in the longitudinal direction over a combined distance of at least 10% of the length of the macrostructure.

5. The catalyst according to claim 1 or 2, wherein The mesh structure includes a plurality of cutouts.

6. The catalyst according to claim 5, wherein The cutout is filled with a cutout material having a lower conductivity than the metal material.

7. The catalyst according to claim 5, wherein The incision material is a solid material.

8. The catalyst according to claim 1 or 2, wherein At least a portion of the mesh structure forms a plurality of parallel flow channels.

9. The structured catalyst according to claim 1 or 2, wherein The sub-portions vary less than 500% / mm along the longitudinal direction.

10. The structured catalyst according to claim 1 or 2, wherein One or more macrostructures are produced by 3D printing.

11. The structured catalyst according to claim 1 or 2, wherein: The one or more macrostructures are produced by bending, cutting and / or welding metal sheets.

12. The structured catalyst according to claim 2, wherein The circumferential wall does not include openings transverse to the longitudinal direction.

13. The structured catalyst according to claim 1 or 2, comprising two or more macrostructures, wherein: At least two macrostructures are electrically connected.

14. The structured catalyst according to claim 13, wherein The second macrostructure is arranged at least partially circumferentially surrounding the first macrostructure.

15. The structured catalyst according to claim 14, wherein The first macrostructure and the second macrostructure are electrically connected at the second end.

16. The structured catalyst according to claim 14, wherein The first macrostructure and the second macrostructure are arranged substantially coaxially.

17. The structured catalyst according to claim 5, wherein At least two of the cutouts have different forms and / or shapes.

18. The structured catalyst according to claim 1 or 2, wherein: The catalyst comprises one or more arrays, each of the one or more arrays comprising a first macrostructure and a second macrostructure, wherein: a) the first macrostructure and the second macrostructure include a three-dimensional network structure; b) the array comprises at least a first conductor and a second conductor, the first conductor and the second conductor being electrically connected to the first macrostructure and the second macrostructure, respectively, and to a power source, wherein the power source is dimensioned to heat at least a portion of the first macrostructure and the second macrostructure to a temperature of at least 500° C. by passing an electric current through the macrostructures, and wherein the conductors are connected to the macrostructures at a location closer to the first end than to the second end, c) the first macrostructure and the second macrostructure are electrically connected via a bridge of conductive material, and d) the array is configured to direct current from the first conductor through the first macrostructure to the second end, then across the bridge, and then through the second macrostructure to the second conductor.

19. The structured catalyst according to claim 1 or 2, wherein: The endothermic reaction is selected from the group consisting of steam methane reforming, hydrogen cyanide formation, methanol cracking, ammonia cracking, reverse water gas shift and dehydrogenation.

20. A reactor system for performing an endothermic reaction of a feed gas, the reactor system comprising: a) a structured catalyst according to any one of claims 1 to 19; b) a pressure housing containing the structured catalyst, the pressure housing comprising an inlet for admitting the feed gas and an outlet for allowing the product gas to exit, wherein the inlet is positioned so that the feed gas enters the structured catalyst at a first end and the product gas exits the catalyst from a second end; as well as c) A thermal insulation layer between the structured catalyst and the pressure housing.

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