Catalytic distillation structured packing, catalytic distillation tower filled with structured packing and application of catalytic distillation structured packing

Abstract

The invention discloses a catalytic distillation structured packing, a catalytic distillation tower filled with the structured packing and application, the catalytic distillation structured packing comprises a plurality of catalytic zones and separation zones which are alternately arranged, and a silk screen catalyst bag is independently arranged in each catalytic zone; the wire mesh catalyst bag comprises a plurality of columnar catalyst bags which are arranged at intervals in the axial direction. Each separation area independently comprises one or more corrugated packing assemblies, each corrugated packing assembly independently comprises two corrugated packing sheets, and each separation area independently comprises 1-8 corrugated packing assemblies. The catalytic rectification filler has the advantages of high specific surface area, low pressure drop, high adaptability, easiness in amplification and the like, and is beneficial to improving the conversion rate and the separation effect in the butene hydroisomerization rectification process.

Description

Technical Field

[0001] This invention belongs to the field of catalytic distillation technology, and particularly relates to a structured packing for catalytic distillation, a catalytic distillation column packed with the structured packing, and its application in the hydroisomerization reaction of butene. Background Technology

[0002] The hydroisomerization of butene-1 to butene-2 ​​is an important technology for utilizing C4 resources. This reaction is reversible, and the conversion rate is limited by equilibrium. Furthermore, the boiling points of butene-1 and isobutene in the reaction feedstock are similar, and they easily form an azeotrope, making separation difficult.

[0003] To address these difficulties industrially, reactive distillation technology is employed. In a reactive distillation column, butene-2, which has a significantly different boiling point from isobutene, is continuously separated from the reaction zone, thereby breaking the equilibrium of the butene hydroisomerization reaction and achieving a higher butene-1 conversion rate. This also solves the problem of the difficulty in separating butene-1 and isobutene.

[0004] Catalytic distillation packing is a core internal component of reactive distillation columns, playing a crucial role in the reactive distillation process. Among them, structured catalytic distillation packing has become widely used in reactive distillation columns due to its advantages such as low pressure drop, easy assembly, and ease of industrial scale-up. Since catalytic reaction and gas-liquid mass transfer occur simultaneously during reactive distillation, catalytic distillation packing must possess both catalytic and gas-liquid mass transfer functions. The structure of the catalytic distillation packing directly affects the efficiency of the reactive distillation process, requiring both thorough mixing of the gas and liquid phases within the column and sufficient contact between the liquid phase and the catalyst.

[0005] For the hydroisomerization process of butene, existing related catalytic distillation packing technologies suffer from problems such as mismatch between the reaction rate and separation rate of butene hydroisomerization, and mismatch between pressure drop, resulting in low conversion rates. Summary of the Invention

[0006] To overcome the problems existing in the prior art, the present invention provides a structured packing for catalytic distillation, a catalytic distillation column packed with the structured packing, and its application. The catalytic distillation packing has advantages such as high specific surface area, low pressure drop, strong adaptability, and easy scale-up, which is beneficial to improving the conversion rate and separation effect of the butene hydroisomerization reaction distillation process.

[0007] One of the objectives of this invention is to provide a catalytic distillation structured packing (for hydroisomerization, especially for butene hydroisomerization), comprising multiple alternating catalytic zones and separation zones, wherein each catalytic zone is independently provided with a wire mesh catalyst pack, the wire mesh catalyst pack comprising multiple columnar catalyst packs arranged at intervals along the axial direction.

[0008] Each columnar catalyst pack is arranged horizontally or with its axial direction parallel to the radial direction of the catalytic distillation structured packing.

[0009] In a preferred embodiment, the columnar catalyst package is a catalyst package with a columnar wire mesh structure, that is, the columnar catalyst package is formed by filling the columnar wire mesh with catalyst.

[0010] The wire mesh catalyst pack is a catalyst pack made by stamping wire mesh. The wire mesh material can be various metal wires, including but not limited to iron wire, steel wire, stainless steel wire, copper wire, nickel wire, aluminum wire, etc.

[0011] In a further preferred embodiment, the column is cylindrical or polygonal, preferably hexagonal, such as a regular hexagonal column.

[0012] In a preferred embodiment, the plurality of columnar catalyst packages arranged axially spaced apart are connected to each other (axially).

[0013] In a further preferred embodiment, two adjacent columnar catalyst packs arranged at intervals along the axial direction are connected by a plate or wire, wherein the plate can be a wire mesh plate, a hollow plate, a solid plate, or a perforated plate, etc.

[0014] In a preferred embodiment, within each catalytic zone, the total volume of the columnar catalyst pack accounts for 50-95% of the volume of the catalytic zone, preferably 65-85%, for example 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90% or 95%.

[0015] In this invention, there is a gap between two axially adjacent columnar catalyst packs. In this way, the reactants react in the columnar catalyst packs, and after the reaction, they enter the gap space between the packs for further remixing. After remixing, they enter the columnar catalyst packs again for reaction. This method further promotes the mixing of reactants and significantly improves the reaction efficiency.

[0016] In a preferred embodiment, each separation zone independently includes one or more corrugated packing assemblies, and each corrugated packing assembly independently includes two corrugated packing sheets, wherein the crests or troughs of the two corrugated packing sheets do not overlap.

[0017] The corrugated packing sheet is corrugated, including multiple peaks and multiple troughs.

[0018] In a further preferred embodiment, the troughs of the two corrugated packing sheets are in the same direction or opposite direction; preferably, when the troughs of the two corrugated packing sheets are in the same direction, the two corrugated packing sheets are stacked at an angle of 20° to 160° (i.e., the included angle between the crests of the two corrugated packing sheets is 20° to 160°), more preferably at an angle of 40° to 120°, for example at an angle of 20°, 40°, 60°, 80°, 90°, 100°, 120°, 140° or 160°.

[0019] The reversal of the troughs of the two corrugated packing sheets refers to flipping the corrugated sheets 180° from front to back. The corrugated packing sheets can have different inclination angles, for example, 30° to 60°. The inclination angle of the corrugated plate refers to the angle between the crest line and the horizontal plane when the corrugated plate is upright.

[0020] The corrugated packing sheet can be a plate-shaped corrugated packing sheet or a wire mesh corrugated packing sheet, such as a metal plate corrugated packing sheet or a metal wire mesh corrugated packing sheet. When it is a plate corrugated packing sheet, the surface of the packing sheet may or may not be embossed. It may or may not be perforated; if perforation is performed, the opening rate is 5% to 95%, for example 5% to 60%, specifically 5% to 15%.

[0021] In a preferred embodiment, the thickness of each corrugated packing assembly is 0.5 to 1.5 times, preferably 0.8 to 1.2 times, of the thickness of each columnar catalyst packing, for example, 0.5 times, 0.6 times, 0.8 times, 1 time, 1.2 times, 1.4 times, or 1.5 times.

[0022] The thickness of the columnar catalyst pack is the same as the thickness of the catalytic zone.

[0023] In a further preferred embodiment, each separation zone independently includes 1 to 8, preferably 1 to 6, of the corrugated packing assemblies, such as 1, 2, 3, 4, 5, 6, 7, and / or 8.

[0024] In another further preferred embodiment, the thickness ratio of each separation zone to each catalytic zone is (0.5-12):1, preferably (0.8-6):1, more preferably (1-4):1, for example 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1 or 8:1.

[0025] In a preferred embodiment, the height of the catalytic distillation structured packing is not particularly limited, for example, it is between 100 and 400 mm, preferably between 150 and 300 mm.

[0026] In this invention, the corrugated packing sheet is assembled in the separation zone and the catalytic zone according to the structure shown in the figure, and then fixed into an integral structure by binding with steel bars or steel wires.

[0027] In a preferred embodiment, the wire mesh catalyst package contains granular catalyst, which can be of any shape, preferably selected from at least one of spherical catalyst, cylindrical catalyst, wheel-shaped catalyst, monoporous column catalyst, porous column catalyst, and irregularly shaped catalyst (preferably clover-shaped and / or tetralea-shaped catalyst).

[0028] In a further preferred embodiment, the catalyst is selected from at least one of clover-shaped catalysts, tetra-shaped catalysts, and monoporous column catalysts, preferably monoporous column catalysts and / or clover-shaped catalysts.

[0029] In a preferred embodiment, the catalyst is selected from hydroisomerization catalysts, and can be any catalyst capable of carrying out hydroisomerization reactions, such as Pd / Al2O3 catalysts.

[0030] In this invention, the hydroisomerization catalyst preferably comprises a support, an active component supported on the support, and an auxiliary agent supported on the support. The support is a mixture of a support matrix and a modified metal. The support matrix is ​​selected from any one or a mixture of two or more of alumina, silica, zirconium oxide, calcium oxide, activated carbon, and molecular sieves. The modified metal is selected from at least one of Group VIB metals, preferably at least one of chromium, molybdenum, and tungsten, more preferably molybdenum, and the modified metal is uniformly distributed within the support matrix. The active component is metal M and / or its oxide, wherein metal M is selected from at least one of palladium, platinum, rhodium, and ruthenium. Based on 100 wt% of the support matrix, the content of the modified metal is 1–15 wt%, preferably 3–10 wt%, for example, 1 wt%, 2 wt%, 4 wt%, 6 wt%, 8 wt%, 10 wt%, 12 wt%, 14 wt%, or 15 wt%. The content of the active component, based on 100 wt% of the carrier, is 0.01–5 wt%, preferably 0.05–1 wt%, for example 0.01 wt%, 0.02 wt%, 0.05 wt%, 0.08 wt%, 0.1 wt%, 0.2 wt%, 0.4 wt%, 0.6 wt%, 0.8 wt%, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, or 5 wt%, wherein the content of the active component is based on the content of the metal element therein. An auxiliary agent is loaded on the carrier (preferably the outer surface), the auxiliary agent being selected from at least one alkaline earth metal and / or its oxides, preferably at least one of calcium, magnesium, and barium. The content of the auxiliary agent, based on 100 wt% of the support, is 0.1–6 wt%, preferably 0.3–4 wt%, for example 0.1 wt%, 0.2 wt%, 0.5 wt%, 0.8 wt%, 1 wt%, 1.2 wt%, 1.5 wt%, 1.8 wt%, 2 wt%, 2.2 wt%, 2.5 wt%, 2.8 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, 5 wt%, 5.5 wt%, or 6 wt%, wherein the content of the auxiliary agent is based on the content of a metal element (e.g., an alkaline earth metal element). The active component and the auxiliary agent are distributed in a protein-like form on the outer surface of the support. The CO-FTIR spectrum of the catalyst is in the range of 2100–2150 cm⁻¹. -3 An absorption peak I is present at point M, preferably M. + —CO (e.g., Pd) + —CO) linear absorption peak; further, the CO-FTIR spectrum of the catalyst is 2050-2100 cm⁻¹. -3 An absorption peak II is present at point M, preferably M. 0 —CO (e.g., Pd) 0—The intensity of the linear absorption peak (CO); furthermore, the intensity of absorption peak I on the CO-FTIR spectrum of the catalyst is greater than the intensity of absorption peak II.

[0031] The preferred hydroisomerization catalyst of this invention can catalyze the hydroisomerization of butene-1 to butene-2, exhibiting advantages such as high butene-1 conversion and high butene-2 ​​selectivity. When applied to the hydroisomerization of mixed C4 molecules, the catalyst has the advantage of low butane content.

[0032] The preferred method for preparing the hydroisomerization catalyst includes: (1) mixing the support matrix powder with the modified metal precursor and an optional binder, followed by molding, drying, and calcination to obtain the support; (2) loading the active component and the optional auxiliary agent onto the support, followed by calcination to obtain the hydroisomerization catalyst. The binder is selected from at least one of polyvinyl alcohol, cellulose, and polyvinylpyrrolidone. The weight ratio of the binder to the support matrix is ​​(0-0.2):1, preferably (0-0.15):1, for example, 0.02:1, 0.04:1, 0.06:1, 0.08:1, 0.1:1, 0.12:1, 0.14:1, 0.16:1, 0.18:1, or 0.2:1.

[0033] A second objective of this invention is to provide a catalytic distillation column (for hydroisomerization, especially for butene hydroisomerization), wherein a feed inlet is provided on the catalytic distillation column, a reaction section and a rectification section are sequentially arranged above the feed inlet, and a stripping section is arranged below the feed inlet, and the reaction section is filled with the catalytic distillation structured packing described in one objective of this invention.

[0034] In a preferred embodiment, the reaction section includes multiple catalyst beds, each of which is independently packed with the catalytic distillation structured packing.

[0035] In a further preferred embodiment, in each catalytic distillation structured packing in the reaction section from bottom to top, the ratio of the number of corrugated packing assemblies in each separation zone to the number of adjacent wire mesh catalyst packs gradually increases; or, in each catalytic distillation structured packing in the reaction section from bottom to top, the ratio of the thickness of each separation zone to the thickness of the adjacent catalytic zone gradually increases.

[0036] In a further preferred embodiment, in each catalytic distillation structured packing in the reaction section from bottom to top, the ratio of the number of corrugated packing assemblies to the number of adjacent wire mesh catalyst packs in each separation zone gradually increases from 1:1 to 8:1 (preferably from 1:1 to 6:1, more preferably from 1:1 to 4:1); or, in each catalytic distillation structured packing in the reaction section from bottom to top, the thickness ratio of each separation zone to the adjacent catalytic zone gradually increases from 1:1 to 8:1 (preferably from 1:1 to 6:1, more preferably from 1:1 to 4:1).

[0037] Through experiments, the inventors discovered that, from bottom to top within the reaction section, the number of corrugated packing sheets in each catalytic distillation structured packing increases in a gradient. Thus, overall, when using the same separation components, this gradient setting results in a higher conversion rate.

[0038] The third objective of this invention is to provide the application of the catalytic distillation structured packing described in the first objective of this invention or the catalytic distillation column described in the second objective of this invention in hydroisomerization, especially in the hydroisomerization of butene.

[0039] The fourth objective of this invention is to provide a method for hydroisomerization of butene-1, comprising: hydroisomerizing butene-1 in a catalytic distillation structured packing as described in the first objective of this invention or in a catalytic distillation column as described in the second objective of this invention to obtain butene-2.

[0040] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values; these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein. In the following, various technical solutions can, in principle, be combined with each other to obtain new technical solutions, which should also be considered as specifically disclosed herein.

[0041] Compared with the prior art, the present invention has the following beneficial effects: the structured packing for catalytic distillation of butene hydroisomerization reaction of the present invention, compared with the prior art, adopts a hexagonal catalyst pack, which improves the space utilization of the catalyst pack. At the same time, corrugated sheets are added to the catalyst pack to provide a larger specific surface area and porosity, enhance gas-liquid mass transfer, and improve the reaction and separation effects of butene hydroisomerization. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the overall catalytic distillation packing structure, 1-separation zone, 2-catalytic zone.

[0043] Figure 2The diagram shows a three-dimensional representation of the overall catalytic distillation packing structure in Example 1 when the ratio of corrugated packing components to wire mesh catalyst packs is 1:1. The thickness of each corrugated packing component is the same as the thickness of the wire mesh catalyst pack.

[0044] Figure 3 The diagram shows a three-dimensional representation of the overall catalytic distillation packing structure in Example 2 when the ratio of corrugated packing components to wire mesh catalyst packs is 2:1. The thickness of each corrugated packing component is the same as the thickness of the wire mesh catalyst pack.

[0045] Figure 4 The diagram shows a three-dimensional representation of the overall catalytic distillation packing structure in Example 2 when the ratio of corrugated packing components to wire mesh catalyst packs is 3:1. The thickness of each corrugated packing component is the same as the thickness of the wire mesh catalyst pack.

[0046] Figure 5 The diagram shows a three-dimensional representation of the overall catalytic distillation packing structure in Example 2 when the ratio of corrugated packing components to wire mesh catalyst packs is 4:1. The thickness of each corrugated packing component is the same as the thickness of the wire mesh catalyst pack. Detailed Implementation

[0047] The present invention will now be described in detail with reference to specific embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0048] It should also be noted that the various specific technical features described in the following embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the various possible combinations will not be described separately in this invention.

[0049] Furthermore, various embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention. The resulting technical solutions are part of the original disclosure of this specification and also fall within the protection scope of the present invention.

[0050] Unless otherwise specified, the raw materials used in the examples and comparative examples are all disclosed in the prior art, such as those that can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0051] The following examples illustrate the use of a C4 feedstock processing unit with a capacity of 220,000 tons / year, employing this catalytic distillation structured packing as an example:

[0052] The catalytic distillation column is provided with a feed inlet. A reaction section and a rectification section are arranged sequentially above the feed inlet, and a stripping section is arranged below the feed inlet. The reaction section is filled with catalytic distillation structured packing, which includes multiple alternating catalytic zones and separation zones. Each catalytic zone is independently provided with a wire mesh catalyst pack, which includes multiple columnar wire mesh catalyst packs arranged axially spaced and connected to each other axially. Each separation zone independently includes one or more corrugated packing assemblies, which each corrugated packing assembly independently includes two corrugated packing sheets.

[0053] In all embodiments, the reactive distillation column had a top pressure of 0.6 MPa, a top condenser temperature of 20°C, a column diameter of 3200 mm, and a reaction section (filled with the structured packing) height of 10 m. A Pd / Al₂O₃ catalyst (Pd weight content 0.38%) was used in the reaction section. The rectification and stripping sections were 7.5 m and 17.5 m high, respectively. C₄ feedstock entered from the bottom of the reaction section, with a hydrogen-to-C₄ molar ratio of 0.02:1. After entering the reactive distillation column, butene-1 underwent a catalytic isomerization reaction in the reaction section to butene-2. Separation of isobutene, isobutane, and butene-2 ​​was achieved through distillation. Butene-2 ​​was collected from the bottom of the column, while the lighter components isobutane, isobutene, and some unreacted butene-1 were collected from the top.

[0054] Example 1

[0055] In this embodiment, the columnar wire mesh structure is a regular hexagonal columnar wire mesh structure, and the catalyst inside the catalyst pack with the regular hexagonal columnar wire mesh structure has a clover-shaped structure. Within each catalytic zone, the columnar catalyst pack occupies 75% of the volume of the catalytic zone. Each separation zone independently includes one corrugated packing assembly, and each corrugated packing assembly independently includes two corrugated packing sheets, which are rotated 180° front to back, with a corrugation angle of 60°. The thickness of the corrugated packing assembly is the same as the thickness of the columnar catalyst pack, thus the thickness ratio of the separation zone to each catalytic zone is 1.

[0056] The overall packing disc has a diameter of 400mm, a height of 200mm, and a specific surface area of ​​223.7m². 2 / m 3 The porosity is 0.610. The specific material balance of the catalytic distillation column is shown in Table 1. The conversion rate of butene-1 is 94.69%.

[0057] Table 1 Material Balance Table for Example 1

[0058]

[0059] Example 2

[0060] In this embodiment, the columnar wire mesh structure is a regular hexagonal columnar wire mesh structure, and the catalyst inside the catalyst pack with the regular hexagonal columnar wire mesh structure has a clover-shaped structure. Within each catalytic zone, the columnar catalyst pack occupies 75% of the volume of the catalytic zone. Each separation zone independently includes two corrugated packing assemblies, each corrugated packing assembly independently comprising two corrugated packing sheets, which are rotated 180° front to back, with a corrugation angle of 45°. The thickness of the corrugated packing assembly is the same as the thickness of the columnar catalyst pack, thus the thickness ratio of the separation zone to each catalytic zone is 2.

[0061] The overall packing disc has a diameter of 400mm, a height of 200mm, and a specific surface area of ​​253.0m². 2 / m 3 The porosity is 0.728. The specific material balance of the catalytic distillation column is shown in Table 2. The conversion rate of butene-1 is 93.97%.

[0062] Table 2 Material Balance Table for Example 2

[0063]

[0064] Example 3

[0065] In this embodiment, the columnar wire mesh structure is a regular hexagonal columnar wire mesh structure, and the catalyst inside the catalyst pack with the regular hexagonal columnar wire mesh structure has a clover-shaped structure. Within each catalytic zone, the columnar catalyst pack occupies 75% of the volume of the catalytic zone. Each separation zone independently includes three corrugated packing assemblies, each corrugated packing assembly independently including two corrugated packing sheets, which are rotated 180° front to back, with a corrugation angle of 30°. The thickness of the corrugated packing assembly is the same as the thickness of the columnar catalyst pack, thus the thickness ratio of the separation zone to each catalytic zone is 3.

[0066] The overall packing disc has a diameter of 400mm, a height of 200mm, and a specific surface area of ​​266.7m². 2 / m 3 The porosity is 0.788. The specific material balance of the catalytic distillation column is shown in Table 3. The conversion rate of butene-1 is 91.73%.

[0067] Table 3 Material Balance Table for Example 3

[0068]

[0069] Example 4

[0070] In this embodiment, the columnar wire mesh structure is a regular hexagonal columnar wire mesh structure, and the catalyst inside the catalyst pack with the regular hexagonal columnar wire mesh structure has a clover-shaped structure. Within each catalytic zone, the columnar catalyst pack occupies 75% of the volume of the catalytic zone. Each separation zone independently includes four corrugated packing assemblies, each corrugated packing assembly independently including two corrugated packing sheets, which are rotated 180° front to back, with a corrugation angle of 60°. The thickness of the corrugated packing assembly is the same as the thickness of the columnar catalyst pack, thus the thickness ratio of the separation zone to each catalytic zone is 4.

[0071] The overall packing disc has a diameter of 400mm, a height of 200mm, and a specific surface area of ​​271.7m². 2 / m 3 The porosity is 0.809. The specific material balance of the catalytic distillation column is shown in Table 4. The conversion rate of butene-1 is 90.14%.

[0072] Table 4 Material Balance Table for Example 4

[0073]

[0074] Example 5

[0075] In this embodiment, Example 2 is repeated, except that the catalyst inside the catalyst package with the hexagonal columnar wire mesh structure is cylindrical. The specific material balance of the catalytic distillation column is shown in Table 5, and the conversion rate of butene-1 is 93.07%.

[0076] Table 5 Material Balance Table for Example 5

[0077]

[0078]

[0079] Example 6

[0080] In this embodiment, Example 2 is repeated, except that the catalyst inside the hexagonal columnar wire mesh catalyst package is a spherical structure. The specific material balance of the catalytic distillation column is shown in Table 6, and the conversion rate of butene-1 is 91.37%.

[0081] Table 6 Material Balance Table for Example 6

[0082]

[0083] Example 7

[0084] In this embodiment, Example 2 is repeated, with the only difference being that the catalyst package containing the hexagonal columnar wire mesh structure has a single-pore columnar structure. The specific material balance of the catalytic distillation column is shown in Table 7, and the conversion rate of butene-1 is 94.44%.

[0085] Table 7 Material Balance Table for Example 7

[0086]

[0087] Example 8

[0088] In this embodiment, the reaction section of the reactive distillation column is divided into three parts from bottom to top: the bottom of the reaction section, the middle of the reaction section, and the top of the reaction section. The bottom of the reaction section is filled with the catalytic distillation structured packing described in Example 1, the middle of the reaction section is filled with the catalytic distillation structured packing described in Example 2, and the top of the reaction section is filled with the catalytic distillation structured packing described in Example 3.

[0089] The specific material balance of the catalytic distillation column is shown in Table 8, with a conversion rate of 94.19% for butene-1.

[0090] Table 8 Material Balance Table for Example 8

[0091]

[0092] Example 9

[0093] In this embodiment, the reaction section of the reactive distillation column is divided into three parts from bottom to top: the bottom of the reaction section, the middle of the reaction section, and the top of the reaction section. The bottom of the reaction section is filled with the catalytic distillation structured packing described in Example 3, the middle of the reaction section is filled with the catalytic distillation structured packing described in Example 2, and the top of the reaction section is filled with the catalytic distillation structured packing described in Example 1.

[0094] The specific material balance of the catalytic distillation column is shown in Table 9, with a conversion rate of 93.58% for butene-1.

[0095] Table 9 Material Balance Table for Example 9

[0096]

[0097]

[0098] Example 10

[0099] In this embodiment, Example 1 is repeated, with the only difference being that the catalyst inside the hexagonal columnar wire mesh catalyst package has a clover-shaped structure. The catalyst is prepared as follows: 50g of alumina support powder is mixed with 15g of ammonium molybdate aqueous solution (10.0wt% molybdenum) and 2g of polyvinyl alcohol, and then bonded for 1 hour, followed by extrusion molding. The mixture is dried at 100℃ for 110 hours and calcined at 850℃ for 4 hours to obtain a modified alumina support. Palladium nitrate is prepared into a palladium-containing acetic acid aqueous solution (0.38wt% palladium), and then 30g of the support is mixed with 21g of the palladium-containing acetic acid aqueous solution for 1 hour. After drying at 110℃ for 12 hours, a catalyst precursor is obtained. The catalyst precursor is mixed with 10g of calcium nitrate aqueous solution (2wt% calcium), washed several times with deionized water, dried at 110℃ for 6 hours, and calcined at 600℃ for 4 hours to obtain the catalyst. The CO-FTIR spectrum of the obtained catalyst is in the range of 2100-2150 cm⁻¹. -3 (Pd + The absorption peak I at -CO is stronger than that at 2050-2100 cm⁻¹. -3 (Pd 0 There is an intensity of absorption peak II at —CO).

[0100] The specific material balance of the catalytic distillation column is shown in Table 10, and the conversion rate of butene-1 is 95.67%.

[0101] Table 10 Material Balance Table for Example 10

[0102]

[0103]

[0104] Example 11

[0105] In this embodiment, Example 2 is repeated, except that the catalyst inside the catalyst package with the regular hexagonal columnar wire mesh structure has a clover-shaped structure, and the catalyst is prepared using the catalyst method mentioned in Example 10.

[0106] The specific material balance of the catalytic distillation column is shown in Table 11, and the conversion rate of butene-1 is 94.74%.

[0107] Table 11 Material Balance Table for Example 11 Components

[0108]

[0109] Example 12

[0110] In this embodiment, Example 3 is repeated, with the only difference being that the catalyst inside the hexagonal columnar wire mesh catalyst package has a clover-shaped structure. The catalyst is prepared as follows: 50g of alumina support powder is mixed with 30g of ammonium molybdate aqueous solution (10.0wt% molybdenum) and 2g of polyvinyl alcohol, and then bonded for 1 hour, followed by extrusion molding. The mixture is dried at 100℃ for 110 hours and calcined at 850℃ for 4 hours to obtain a modified alumina support. Palladium nitrate is prepared into a palladium-containing acetic acid aqueous solution (0.45wt% palladium), and then 30g of the support is mixed with 23g of the palladium-containing acetic acid aqueous solution for 1 hour. After drying at 110℃ for 12 hours, a catalyst precursor is obtained. The catalyst precursor is mixed with 10g of calcium nitrate aqueous solution (3wt% calcium), then washed several times with deionized water, dried at 110℃ for 6 hours, and calcined at 600℃ for 4 hours to obtain the catalyst. The CO-FTIR spectrum of the obtained catalyst is in the range of 2100-2150 cm⁻¹. -3 (Pd + The absorption peak I at -CO is stronger than that at 2050-2100 cm⁻¹. -3 (Pd 0 There is an intensity of absorption peak II at —CO).

[0111] The specific material balance of the catalytic distillation column is shown in Table 12, and the conversion rate of butene-1 is 92.99%.

[0112] Table 12 Material Balance Table for Example 12

[0113]

[0114] Example 13

[0115] In this embodiment, Example 4 is repeated, except that the catalyst inside the catalyst package with the regular hexagonal columnar wire mesh structure has a clover-shaped structure, and the catalyst is prepared using the catalyst method mentioned in Example 12.

[0116] The specific material balance of the catalytic distillation column is shown in Table 13, and the conversion rate of butene-1 is 91.52%.

[0117] Table 13 Material Balance Table for Example 13

[0118]

[0119] Example 14

[0120] In this embodiment, Example 8 is repeated, with the only difference being that the catalyst inside the hexagonal columnar wire mesh catalyst package has a clover-shaped structure. The catalyst is prepared as follows: 50g of alumina support powder is mixed with 30g of ammonium molybdate aqueous solution (13.0wt% molybdenum) and 2g of polyvinyl alcohol, and then bonded for 1 hour, followed by extrusion molding. The mixture is dried at 100℃ for 110 hours and calcined at 850℃ for 4 hours to obtain a modified alumina support. Palladium nitrate is prepared into a palladium-containing acetic acid aqueous solution (0.56wt% palladium), and then 30g of the support is mixed with 25g of the palladium-containing acetic acid aqueous solution for 1 hour. After drying at 110℃ for 12 hours, a catalyst precursor is obtained. The catalyst precursor is mixed with 20g of calcium nitrate aqueous solution (3wt% calcium), then washed several times with deionized water, dried at 110℃ for 6 hours, and calcined at 600℃ for 4 hours to obtain the catalyst. The CO-FTIR spectrum of the obtained catalyst is in the range of 2100-2150 cm⁻¹. -3 (Pd + The absorption peak I at -CO is stronger than that at 2050-2100 cm⁻¹. -3 (Pd 0 There is an intensity of absorption peak II at —CO).

[0121] The specific material balance of the catalytic distillation column is shown in Table 14, and the conversion rate of butene-1 is 95.38%.

[0122] Table 14 Material Balance Table for Example 14

[0123]

[0124] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

Claims

1. A structured packing for catalytic distillation, comprising a plurality of alternating catalytic zones and separation zones, wherein each catalytic zone is independently provided with a wire mesh catalyst pack, the wire mesh catalyst pack comprising a plurality of columnar catalyst packs arranged at intervals along the axial direction.

2. The catalytic distillation structured packing according to claim 1, characterized in that, The columnar catalyst package is a catalyst package with a columnar wire mesh structure; preferably, the columnar shape is cylindrical or polygonal; and / or, The plurality of columnar catalyst packs arranged at intervals along the axial direction are connected to each other. Preferably, two adjacent columnar catalyst packs arranged at intervals along the axial direction are connected by a plate or a wire.

3. The catalytic distillation structured packing according to claim 1, characterized in that, Within each catalytic zone, the total volume of the columnar catalyst package accounts for 50-95% of the volume of the catalytic zone, preferably 65-85%.

4. The catalytic distillation structured packing according to claim 1, characterized in that, Each separation zone independently comprises one or more corrugated packing assemblies, and each corrugated packing assembly independently comprises two corrugated packing sheets.

5. The catalytic distillation structured packing according to claim 4, characterized in that, The thickness of each corrugated packing assembly is 0.5 to 1.5 times, preferably 0.8 to 1.2 times, the thickness of each columnar catalyst packing; and / or, Each separation zone independently includes 1 to 8, preferably 1 to 6, of the corrugated packing assemblies.

6. The catalytic distillation structured packing according to any one of claims 1 to 5, characterized in that, The wire mesh catalyst package contains granular catalyst, which can be of any shape, preferably selected from at least one of spherical catalyst, cylindrical catalyst, wheel-shaped catalyst, monoporous column catalyst, porous column catalyst, and irregularly shaped catalyst. The irregularly shaped catalyst is preferably a clover-shaped catalyst and / or a tetralea-shaped catalyst.

7. A catalytic distillation column, wherein a feed inlet is provided on the catalytic distillation column, a reaction section and a rectification section are sequentially arranged above the feed inlet, and a stripping section is arranged below the feed inlet, and the reaction section is filled with the catalytic distillation structured packing according to any one of claims 1 to 6.

8. The catalytic distillation column according to claim 7, characterized in that, The reaction section includes multiple catalyst beds, each of which is independently filled with the catalytic distillation structured packing.

9. The catalytic distillation column according to claim 8, characterized in that, In each catalytic distillation structured packing within the reaction section from bottom to top, the ratio of the number of corrugated packing assemblies to the number of wire mesh catalyst packs in each separation zone gradually increases; or, in each catalytic distillation structured packing within the reaction section from bottom to top, the ratio of the thickness of the separation zone to the thickness of the catalytic zone gradually increases.

10. The catalytic distillation column according to claim 8, characterized in that, In each catalytic distillation structured packing in the reaction section from bottom to top, the ratio of the number of corrugated packing assemblies to the number of wire mesh catalyst packs in each separation zone gradually increases from 1:1 to 8:1; or, in each catalytic distillation structured packing in the reaction section from bottom to top, the thickness ratio of the separation zone to the catalytic zone gradually increases from 1:1 to 8:

1.

11. The application of the catalytic distillation structured packing according to any one of claims 1 to 6 or the catalytic distillation column according to any one of claims 7 to 10 in hydroisomerization, especially in the hydroisomerization of butene.

12. A method for the hydroisomerization of butene-1, comprising: Butene-1 is hydroisomerized in the catalytic distillation structured packing as described in any one of claims 1 to 6 or in the catalytic distillation column as described in any one of claims 7 to 10 to obtain butene-2.

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