Carrier, isobutane dehydrogenation catalyst and preparation method of isobutane dehydrogenation catalyst

Abstract

The invention relates to a carrier, an isobutane dehydrogenation catalyst and a preparation method of the isobutane dehydrogenation catalyst, and relates to the technical field of catalysts, the preparation method of the carrier comprises the following steps: mixing aluminum stone, a binder and a lubricant to obtain a mixture; carrying out extrusion molding on the mixture, and then carrying out drying and pelletizing to obtain a strip-shaped material; and carrying out first roasting on the strip-shaped material to obtain the carrier. The carrier with excellent comprehensive performance is prepared firstly, alkali metal is added in the impregnation process, the metal function of the catalyst is improved, the activity of the catalyst is guaranteed, the acid function is inhibited, carbon deposition is reduced, transition metal is added, the selectivity of the catalyst is improved, and therefore the isobutane dehydrogenation catalyst with excellent performance and long service life is prepared. And the defects in the prior art are overcome.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts, and in particular to a carrier, an isobutane dehydrogenation catalyst and a preparation method thereof. Background Art

[0002] Dehydrogenation of isobutane to produce isobutylene is an important process in chemical production. As a key chemical raw material, isobutylene plays a vital role in the production of a variety of chemical products such as MTBE (methyl tert-butyl ether), tert-butyl alcohol, butyl rubber, polyisobutylene, and organic glass. With the rapid development of the chemical industry, the demand for isobutylene is growing, and the traditional butene supply channels can no longer meet the market demand. Therefore, the development and application of butane dehydrogenation to butene technology is particularly important. It has far-reaching significance and good industrial application prospects for alleviating the current situation of insufficient butene supply and promoting the sustainable development of the chemical industry.

[0003] In the process of isobutane dehydrogenation, the selection and use of catalysts is one of the key factors. At present, the widely used isobutane dehydrogenation catalysts in industry mainly include chromium oxide / aluminum oxide catalysts in the Catofin process of ABB Lummus and platinum tin / aluminum oxide catalysts in the Oleflex process of UOP. These two types of catalysts have their own characteristics. Among them, chromium-based catalysts (i.e., chromium oxide / aluminum oxide catalysts) have certain competitive advantages because of their relatively low requirements for impurities in raw materials and relatively low prices.

[0004] However, chromium-based catalysts also have some obvious shortcomings in practical applications. Since this type of catalyst is easily deactivated by carbon deposition, its catalytic performance gradually decreases with the extension of usage time. In order to maintain the activity of the catalyst, it needs to be regenerated every 15-30 minutes. This frequent regeneration operation not only increases the energy consumption and operation complexity in the production process, but also seriously shortens the service life of the catalyst. Therefore, the development of an isobutane dehydrogenation catalyst with excellent performance and long service life is of great significance for improving production efficiency, reducing production costs, and promoting the green development of the chemical industry. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a carrier, an isobutane dehydrogenation catalyst and a preparation method thereof.

[0006] In a first aspect, the present invention provides a carrier, wherein the preparation method of the carrier comprises the following steps:

[0007] mixing aluminum stone, a binder and a lubricant to obtain a mixture;

[0008] The mixed material is extruded into strips, and then dried and pelletized to obtain strips;

[0009] Carrying out a first calcination of the strip material to obtain the carrier;

[0010] Wherein, the weight ratio of the aluminum stone, the binder and the lubricant is (65-90):(5-10):(1-5);

[0011] The working condition parameters of the first calcination include: temperature of 600° C.-700° C., and time of 2 h-6 h.

[0012] Furthermore, the diaspore includes one or a mixture of pseudo-boehmite, gibbsite, nordstromite, γ-Al2O3 and ρ-Al2O3; the binder includes acid or aluminum sol; the lubricant includes one or a mixture of polypropylene, polyethylene, polyethylene glycol and sesbania powder.

[0013] Furthermore, the working condition parameters of the extrusion molding include: the diameter of the molded product is 2mm-5mm, and the length is 20cm; the working condition parameters of the drying and pelletizing include: drying at 120℃-150℃ for 2h-4h, and then pelletizing to obtain the strip material with a diameter of 3mm and a length of 8mm.

[0014] Furthermore, the physical and chemical properties of the carrier include: strength>160N / cm, water absorption rate 40%-55%, specific surface area 80m 2 / g-120m 2 / g, abrasion<0.1wt%.

[0015] In a second aspect, the present invention provides a method for preparing an isobutane dehydrogenation catalyst, the preparation method comprising the following steps:

[0016] Obtaining the vector according to any one of the first aspects;

[0017] Dissolving a soluble chromium-containing compound, an alkali metal compound, and a transition metal compound in water to obtain an impregnation solution;

[0018] The impregnation liquid and the carrier are impregnated by equal volume impregnation, and then drained and dried to obtain an intermediate;

[0019] The intermediate is subjected to a second calcination to obtain the isobutane dehydrogenation catalyst.

[0020] Furthermore, the soluble chromium-containing compound includes at least one of chromium nitrate, chromic anhydride and potassium chromate, the alkali metal compound includes at least one of potassium sulfate, potassium hydroxide, sodium hydroxide and sodium sulfate, and the transition metal compound includes at least two of zirconium carbonate, zirconium nitrate, magnesium nitrate, ammonium molybdate, nickel nitrate and basic nickel carbonate.

[0021] Furthermore, the weight ratio of water: soluble chromium-containing compound: transition metal compound: alkali metal compound in the impregnation solution is (40-50): (45-55): (1-4): (0-2).

[0022] Furthermore, the working condition parameters of the second calcination include: temperature of 600° C.-700° C., and time of 6 h-8 h.

[0023] In a third aspect, the present invention provides an isobutane dehydrogenation catalyst, wherein the isobutane dehydrogenation catalyst is prepared by the preparation method of the isobutane dehydrogenation catalyst described in any one of the second aspects.

[0024] Further, the carrier of the isobutane dehydrogenation catalyst is a cylindrical carrier with a diameter of 3.2 mm ± 0.5 mm, a specific surface area of ​​less than 120 m2 / g, and a pore size of 5 nm-12 nm;

[0025] In percentage by weight, the isobutane dehydrogenation catalyst comprises:

[0026] Aluminum oxide 60-90%, chromium oxide 20-24%, sodium oxide 0.5-2%, zirconium oxide 0.5-2%, molybdenum oxide 0.1-0.5%.

[0027] The above technical solution provided by the embodiment of the present invention has at least the following advantages compared with the prior art:

[0028] The embodiment of the present invention provides a carrier, an isobutane dehydrogenation catalyst and a preparation method thereof. The present invention first prepares a carrier with excellent comprehensive performance, and then increases alkali metals in the impregnation process to improve the catalyst metal function to ensure catalyst activity, inhibits acidic function to reduce carbon deposition, and increases transition metals to improve catalyst selectivity, thereby preparing an isobutane dehydrogenation catalyst with excellent performance and long service life, thereby making up for the deficiencies of the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0031] Figure 1 A schematic flow chart of a method for preparing a carrier provided in an embodiment of the present invention.

[0032] Figure 2A schematic flow chart of a method for preparing an isobutane dehydrogenation catalyst provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0035] In a first aspect, the present invention provides a vector, such as Figure 1 As shown, the preparation method of the carrier comprises the following steps:

[0036] mixing aluminum stone, a binder and a lubricant to obtain a mixture;

[0037] The mixed material is extruded into strips, and then dried and pelletized to obtain strips;

[0038] Carrying out a first calcination of the strip material to obtain the carrier;

[0039] Wherein, the weight ratio of the aluminum stone, the binder and the lubricant is (65-90):(5-10):(1-5);

[0040] The working condition parameters of the first calcination include: temperature of 600° C.-700° C., and time of 2 h-6 h.

[0041] The embodiment of the present invention provides a carrier. The present invention first prepares a carrier with excellent comprehensive performance, and then increases alkali metals in the impregnation process to improve the catalyst metal function to ensure catalyst activity, inhibits acidic function to reduce carbon deposition, and increases transition metals to improve catalyst selectivity, thereby preparing an isobutane dehydrogenation catalyst with excellent performance and long service life, which makes up for the shortcomings of the prior art.

[0042] In some specific embodiments, the aluminum stone is pseudo-boehmite, gibbsite, nordstromite, γ-Al2O 3、One or a mixture of ρ-Al2O3. Preferred are gibbsite, pseudo-boehmite or γ-Al2O3; the binder, acid and diaspore in the mixed powder form aluminum sol, which binds the components together to form a paste that can be extruded. The acid used includes acids such as nitric acid, formic acid, acetic acid, propionic acid and hydrochloric acid, preferably nitric acid or acetic acid. Alternatively, aluminum sol can be used instead. When an acid is used as a binder, the most preferred is an aqueous nitric acid solution, wherein the weight ratio of nitric acid to water is 1:1.25-10. The lubricant is polypropylene, polyethylene, polyethylene glycol, sesbania powder, etc., preferably sesbania powder or polypropylene.

[0043] In some specific embodiments, the working condition parameters of the extrusion molding include: the diameter of the molded object is 2mm-5mm, and the length is 20cm; the working condition parameters of the drying and pelletizing include: drying at 120℃-150℃ for 2h-4h, and then pelletizing to obtain the strip material with a diameter of 3mm and a length of 8mm.

[0044] In some specific embodiments, the physical and chemical properties of the carrier include: strength> 160N / cm, water absorption rate 40%-55%, specific surface area 80m 2 / g-120m 2 / g, abrasion<0.1wt%.

[0045] In a second aspect, the present invention provides a method for preparing an isobutane dehydrogenation catalyst, such as Figure 2 As shown, the preparation method comprises the following steps:

[0046] Obtaining the vector according to any one of the first aspects;

[0047] Dissolving a soluble chromium-containing compound, an alkali metal compound, and a transition metal compound in water to obtain an impregnation solution;

[0048] The impregnation liquid and the carrier are impregnated by equal volume impregnation, and then drained and dried to obtain an intermediate;

[0049] The intermediate is subjected to a second calcination to obtain the isobutane dehydrogenation catalyst.

[0050] In some specific embodiments, the soluble chromium-containing compound includes at least one of chromium nitrate, chromic anhydride and potassium chromate, the alkali metal compound includes at least one of potassium sulfate, potassium hydroxide, sodium hydroxide and sodium sulfate, and the transition metal compound includes at least two of zirconium carbonate, zirconium nitrate, magnesium nitrate, ammonium molybdate, nickel nitrate and basic nickel carbonate.

[0051] In some specific embodiments, the weight ratio of water: soluble chromium-containing compound: transition metal compound: alkali metal compound in the impregnation solution is (40-50): (45-55): (1-4): (0-2).

[0052] In some specific embodiments, the working condition parameters of the second calcination include: temperature of 600° C.-700° C., and time of 6 h-8 h.

[0053] In a third aspect, the present invention provides an isobutane dehydrogenation catalyst, wherein the isobutane dehydrogenation catalyst is prepared by the preparation method of the isobutane dehydrogenation catalyst described in any one of the second aspects.

[0054] In some specific embodiments, the carrier of the isobutane dehydrogenation catalyst is a cylindrical carrier with a diameter of 3.2 mm ± 0.5 mm, a specific surface area of ​​less than 120 m2 / g, and a pore size of 5 nm-12 nm;

[0055] In percentage by weight, the isobutane dehydrogenation catalyst comprises:

[0056] Aluminum oxide 60-90%, chromium oxide 20-24%, sodium oxide 0.5-2%, zirconium oxide 0.5-2%, molybdenum oxide 0.1-0.5%.

[0057] It should be noted that the component raw materials involved in the isobutane dehydrogenation catalyst and its preparation method and application provided in the embodiments of the present invention, unless otherwise specified or specified, can be directly commercially available products or homemade using existing public preparation methods; at the same time, the steps and parameters involved, unless otherwise specified or specified, can be carried out according to the processing technology of the prior art or directly using existing equipment, and the present invention document will not repeat them one by one.

[0058] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are intended only to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples that do not specify specific conditions are usually measured according to national standards. If there is no corresponding national standard, then the conditions recommended by the manufacturer are followed.

[0059] Example 1

[0060] This example provides a carrier, and its preparation method includes the following steps: adding 825g of aluminum hydroxide, 100g of pseudo-boehmite, and 3g of polypropylene into a kneader; weighing 70g of concentrated nitric acid and adding it to 200g of water to prepare a nitric acid solution, and adding this solution to the mixture, kneading for 30 minutes, and extruding strips on a 3.5mm orifice plate; drying the extruded strip carrier at 110°C for 2 hours, pelletizing, heating to 650°C at a rate of 2°C per minute, and roasting at this temperature for 4 hours to obtain carrier A.

[0061] Example 2

[0062] This example provides a carrier, and its preparation method includes the following steps: adding 825g of aluminum hydroxide, 100g of γ-Al2O3, and 3g of polypropylene into a kneader; weighing 70g of concentrated nitric acid and adding it to 200g of water to prepare a nitric acid solution, and adding this solution to the mixture, kneading for 30 minutes, and extruding strips on a 3.5mm orifice plate; drying the extruded strip carrier at 110°C for 2 hours, pelletizing, heating to 650°C at a rate of 2°C per minute, and calcining at this temperature for 4 hours to obtain carrier B.

[0063] Example 3

[0064] This example provides a carrier, and its preparation method includes the following steps: adding 825g of aluminum hydroxide, 100g of γ-alumina, and 3g of sesbania powder into a kneader and mixing them evenly; weighing 70g of concentrated nitric acid and adding it to 200g of water to prepare a nitric acid solution, and adding the solution to the mixture, kneading for 30 minutes, and extruding strips on a 3.5mm orifice plate; drying the extruded strip carrier at 110°C for 2 hours, pelletizing, heating to 650°C at a rate of 2°C per minute, and calcining at this temperature for 4 hours to obtain carrier C.

[0065] Example 4

[0066] This example provides a carrier, and its preparation method includes the following steps: adding 825g of aluminum hydroxide, 100g of pseudo-boehmite, and 3g of sesbania powder into a kneader and mixing them evenly; weighing 70g of concentrated nitric acid and adding it to 200g of water to prepare a nitric acid solution, and adding the solution to the mixture, kneading for 30 minutes, and extruding strips on a 3.5mm orifice plate; drying the extruded strip carrier at 110°C for 2 hours, pelletizing, heating to 650°C at a rate of 2°C per minute, and roasting at this temperature for 4 hours to obtain carrier D.

[0067] The physical properties of the carriers obtained in Examples 1 to 4 are shown in Table 1. Carrier A has better performance, and carrier A is selected for the preparation of isobutane dehydrogenation catalysts in subsequent Examples 5 to 12 and Comparative Examples 1 to 4.

[0068] Table 1

[0069] project Vector A Vector B Vector C Carrier D Strength, N / cm 229.7 92.3 112.5 143.6 <![CDATA[Specific surface area, m 2 / g]]> 142 98 106 114 Water absorption, % 52.1 48.8 46.6 44.3

[0070] Example 5

[0071] Weigh 52g of chromic anhydride, 0.9g of sodium hydroxide, and 2.5g of zirconium carbonate, and dissolve them in 45.5g of water to obtain an impregnation solution; weigh 100g of the carrier and add it to a beaker; slowly add 100g of the impregnation solution to the beaker to cover the carrier, let it stand for 30 minutes to drain, place it in an 80℃ water bath and stir it every 10 minutes until the surface of the catalyst is air-dried. Place it in a 120℃ oven and dry it for 2 hours to obtain a dry catalyst; calcine the dry catalyst in a hydrothermal aging device at a calcination temperature of 650℃, a calcination time of 8 hours, and a heating rate of 5℃ / min. When the catalyst is naturally cooled to below 200℃, catalyst A is obtained.

[0072] Example 6

[0073] Weigh 52g of chromic anhydride, 1.14g of sodium hydroxide, and 2.5g of zirconium carbonate, and dissolve them in 45.5g of water to obtain an impregnation solution; weigh 100g of the carrier and add it to a beaker; slowly add 100g of the impregnation solution to the beaker to cover the carrier, let it stand for 30 minutes to drain, place it in an 80℃ water bath and stir it every 10 minutes until the surface of the catalyst is air-dried. Put it in a 120℃ oven and dry it for 2 hours to obtain a dry catalyst; calcine the dry catalyst in a hydrothermal aging device at a calcination temperature of 650℃, a calcination time of 8 hours, and a heating rate of 5℃ / min. When the catalyst is naturally cooled to below 200℃, catalyst B is obtained.

[0074] Example 7

[0075] Weigh 52g of chromic anhydride, 1.14g of sodium hydroxide, 2.5g of zirconium carbonate, and 0.43g of basic nickel carbonate, and dissolve them in 45.07g of water to obtain an impregnation solution; weigh 100g of the carrier and add it to a beaker; slowly add 100g of the impregnation solution to the beaker to cover the carrier, let it stand for 30 minutes to drain, place it in an 80℃ water bath and stir it every 10 minutes until the surface of the catalyst is air-dried. Put it in a 120℃ oven and dry it for 2 hours to obtain a dry catalyst; calcine the dry catalyst in a hydrothermal aging device at a calcination temperature of 650℃, a calcination time of 8 hours, and a heating rate of 5℃ / min. When the catalyst is naturally cooled to below 200℃, catalyst C is obtained.

[0076] Example 8

[0077] Weigh 52g of chromic anhydride, 1.4g of sodium hydroxide, 2.5g of zirconium carbonate, and 0.3g of ammonium dimolybdate, and dissolve them in 45g of water to obtain an impregnation solution; weigh 100g of the carrier and add it to a beaker; slowly add 100g of the impregnation solution to the beaker to cover the carrier, let it stand for 30 minutes to drain, place it in an 80℃ water bath and stir it every 10 minutes until the surface of the catalyst is air-dried. Put it in a 120℃ oven and dry it for 2 hours to obtain a dried catalyst; calcine the dried catalyst in a hydrothermal aging device at a calcination temperature of 650℃, a calcination time of 8 hours, and a heating rate of 5℃ / min. When the catalyst is naturally cooled to below 200℃, catalyst D is obtained.

[0078] Example 9

[0079] Weigh 52g of chromic anhydride, 1.14g of sodium hydroxide, 2.5g of zirconium carbonate, and 0.3g of ammonium dimolybdate, and dissolve them in 45.2g of water to obtain an impregnation solution; weigh 100g of the carrier and add it to a beaker; slowly add 100g of the impregnation solution to the beaker to cover the carrier, let it stand for 30 minutes to drain, place it in an 80℃ water bath and stir it every 10 minutes until the surface of the catalyst is air-dried. Place it in a 120℃ oven and dry it for 2 hours to obtain a dry catalyst; calcine the dry catalyst in a hydrothermal aging device at a calcination temperature of 650℃, a calcination time of 8 hours, and a heating rate of 5℃ / min. When the catalyst naturally cools down to below 200℃, catalyst E is obtained.

[0080] Example 10

[0081] Weigh 52g of chromic anhydride, 1.14g of sodium hydroxide, 2.5g of zirconium carbonate, and 0.5g of ammonium dimolybdate, and dissolve them in 45.07g of water to obtain an impregnation solution; weigh 100g of the carrier and add it to a beaker; slowly add 100g of the impregnation solution to the beaker to cover the carrier, let it stand for 30 minutes to drain, place it in an 80℃ water bath and stir it every 10 minutes until the surface of the catalyst is air-dried. Put it in a 120℃ oven and dry it for 2 hours to obtain a dried catalyst; calcine the dried catalyst in a hydrothermal aging device at a calcination temperature of 650℃, a calcination time of 8 hours, and a heating rate of 5℃ / min. When the catalyst is naturally cooled to below 200℃, catalyst F is obtained.

[0082] Embodiment 11

[0083] Weigh 52g of chromic anhydride, 1.14g of sodium hydroxide, 2.5g of zirconium carbonate, and 0.2g of ammonium dimolybdate, and dissolve them in 45.3g of water to obtain an impregnation solution; weigh 100g of the carrier and add it to a beaker; slowly add 100g of the impregnation solution to the beaker to cover the carrier, let it stand for 30 minutes to drain, place it in an 80℃ water bath and stir it every 10 minutes until the surface of the catalyst is air-dried. Put it in a 120℃ oven and dry it for 2 hours to obtain a dried catalyst; calcine the dried catalyst in a hydrothermal aging device at a calcination temperature of 650℃, a calcination time of 8 hours, and a heating rate of 5℃ / min. When the catalyst is naturally cooled to below 200℃, catalyst G is obtained.

[0084] Example 12

[0085] Weigh 52g of chromic anhydride, 1.14g of sodium hydroxide, 2.5g of zirconium carbonate, and 0.4g of ammonium dimolybdate, and dissolve them in 45.1g of water to obtain an impregnation solution; weigh 100g of the carrier and add it to a beaker; slowly add 100g of the impregnation solution to the beaker to cover the carrier, let it stand for 30 minutes to drain, place it in an 80℃ water bath and stir it every 10 minutes until the surface of the catalyst is air-dried. Put it in a 120℃ oven and dry it for 2 hours to obtain a dried catalyst; calcine the dried catalyst in a hydrothermal aging device at a calcination temperature of 650℃, a calcination time of 8 hours, and a heating rate of 5℃ / min. When the catalyst is naturally cooled to below 200℃, catalyst H is obtained.

[0086] Comparative Example 1

[0087] Weigh 52g of chromic anhydride, 2.5g of zirconium carbonate, 1.13g of potassium hydroxide, and 0.3g of ammonium dimolybdate, and dissolve them in 44.07g of water to obtain an impregnation solution; weigh 100g of the carrier and add it to a beaker; slowly add 100g of the impregnation solution to the beaker to cover the carrier, let it stand for 30 minutes to drain, place it in an 80℃ water bath and stir it every 10 minutes until the surface of the catalyst is air-dried. Put it in a 120℃ oven and dry it for 2 hours to obtain a dried catalyst; calcine the dried catalyst in a hydrothermal aging device at a calcination temperature of 650℃, a calcination time of 8 hours, and a heating rate of 5℃ / min. When the catalyst is naturally cooled to below 200℃, catalyst I is obtained.

[0088] Comparative Example 2

[0089] Weigh 52g of chromic anhydride, 2.5g of zirconium carbonate, and 1.14g of sodium hydroxide, and dissolve them in 45.5g of water to obtain an impregnation solution; weigh 100g of the carrier and add it to a beaker; slowly add 100g of the impregnation solution to the beaker to cover the carrier, let it stand for 30 minutes to drain, place it in an 80℃ water bath and stir it every 10 minutes until the surface of the catalyst is air-dried. Put it in a 120℃ oven and dry it for 2 hours to obtain a dry catalyst; calcine the dry catalyst in a hydrothermal aging device at a calcination temperature of 650℃, a calcination time of 8 hours, and a heating rate of 5℃ / min. When the catalyst is naturally cooled to below 200℃, catalyst J is obtained.

[0090] Comparative Example 3

[0091] Weigh 52g of chromic anhydride, 2.5g of zirconium carbonate, 1.14g of sodium hydroxide, 0.43g of basic nickel carbonate, and 0.3g of ammonium dimolybdate and dissolve them in 44.77g of water to obtain an impregnation solution; weigh 100g of the carrier and add it to a beaker; slowly add 100g of the impregnation solution to the beaker to cover the carrier, let it stand for 30 minutes to drain, place it in an 80℃ water bath and stir it every 10 minutes until the surface of the catalyst is air-dried. Put it in a 120℃ oven and dry it for 2 hours to obtain a dried catalyst; calcine the dried catalyst in a hydrothermal aging device at a calcination temperature of 650℃, a calcination time of 8 hours, and a heating rate of 5℃ / min. When the catalyst is naturally cooled to below 200℃, catalyst K is obtained.

[0092] Comparative Example 4

[0093] Weigh 52g of chromic anhydride, 1.14g of sodium hydroxide, and 0.3g of ammonium dimolybdate and dissolve them in 47.27g of water to obtain an impregnation solution; weigh 100g of the carrier and add it to a beaker; slowly add 100g of the impregnation solution to the beaker to cover the carrier, let it stand for 30 minutes to drain, place it in an 80℃ water bath and stir it every 10 minutes until the surface of the catalyst is air-dried. Put it in a 120℃ oven and dry it for 2 hours to obtain a dried catalyst; calcine the dried catalyst in a hydrothermal aging device at a calcination temperature of 650℃, a calcination time of 8 hours, and a heating rate of 5℃ / min. When the catalyst is naturally cooled to below 200℃, catalyst L is obtained.

[0094] Comparative Example 5

[0095] Fresh catalyst M loaded in a device of a domestic private enterprise was taken as a comparison agent. This catalyst is a foreign catalyst, which is widely used in domestic devices and its catalyst performance is recognized by the user.

[0096] The process flow adopted is the existing fixed bed process flow, the reactor is a constant temperature reactor, and the specific control parameters are as follows: the isobutane space velocity is 1h-1, the isobutane pressure is 50kPa, and the bed temperature is 560℃. The results are shown in Table 2.

[0097] Table 2 Catalyst evaluation data

[0098] Sample name Conversion rate Selectivity Catalyst A 55.38 86.09 Catalyst B 54.13 87.9 Catalyst C 51.75 88.95 Catalyst D 52.45 87.56 Catalyst E 51.03 91.37 Catalyst F 52.55 88.84 Catalyst G 51.62 90 Catalyst H 54.09 89.18 Catalyst I 55.22 85.05 Catalyst J 53.97 87.33 Catalyst K 57.69 79.93 Catalyst L 56.04 81.09 Catalyst M 52.86 90.11 Catalyst A 55.38 86.09

[0099] Various embodiments of the present invention may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present invention; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0100] The foregoing is merely a specific embodiment of the present invention, which enables those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A carrier, characterized in that The preparation method of the carrier comprises the following steps: mixing aluminum stone, a binder and a lubricant to obtain a mixture; The mixed material is extruded into strips, and then dried and pelletized to obtain strips; Carrying out a first calcination of the strip material to obtain the carrier; Wherein, the weight ratio of the aluminum stone, the binder and the lubricant is (65-90):(5-10):(1-5); The working condition parameters of the first calcination include: temperature of 600° C.-700° C., and time of 2 h-6 h.

2. The carrier according to claim 1, characterized in that The diaspore includes one or a mixture of pseudo-boehmite, gibbsite, nordstromite, γ-Al2O3 and ρ-Al2O3; the binder includes acid or aluminum sol; the lubricant includes one or a mixture of polypropylene, polyethylene, polyethylene glycol and sesbania powder.

3. The carrier according to claim 1, characterized in that The working condition parameters of the extrusion molding include: the diameter of the molded product is 2mm-5mm, and the length is 20cm; the working condition parameters of the drying and pelletizing include: drying at 120℃-150℃ for 2h-4h, and then pelletizing to obtain the strip material with a diameter of 3mm and a length of 8mm.

4. The carrier according to claim 1, characterized in that The physical and chemical properties of the carrier include: strength>160N / cm, water absorption rate 40%-55%, specific surface area 80m 2 / g-120m 2 / g, abrasion<0.1wt%.

5. A method for preparing an isobutane dehydrogenation catalyst, characterized in that: The preparation method comprises the following steps: Obtaining the vector according to any one of claims 1 to 4; Dissolving a soluble chromium-containing compound, an alkali metal compound, and a transition metal compound in water to obtain an impregnation solution; The impregnation liquid and the carrier are impregnated by equal volume impregnation, and then drained and dried to obtain an intermediate; The intermediate is subjected to a second calcination to obtain the isobutane dehydrogenation catalyst.

6. The method for preparing an isobutane dehydrogenation catalyst according to claim 5, characterized in that: The soluble chromium-containing compound includes at least one of chromium nitrate, chromic anhydride and potassium chromate, the alkali metal compound includes at least one of potassium sulfate, potassium hydroxide, sodium hydroxide and sodium sulfate, and the transition metal compound includes at least two of zirconium carbonate, zirconium nitrate, magnesium nitrate, ammonium molybdate, nickel nitrate and basic nickel carbonate.

7. The method for preparing an isobutane dehydrogenation catalyst according to claim 5, characterized in that: The weight ratio of water: soluble chromium-containing compound: transition metal compound: alkali metal compound in the impregnation solution is (40-50): (45-55): (1-4): (0-2).

8. The method for preparing an isobutane dehydrogenation catalyst according to claim 5, characterized in that: The working condition parameters of the second calcination include: temperature of 600° C.-700° C. and time of 6 h-8 h.

9. An isobutane dehydrogenation catalyst, characterized in that: The isobutane dehydrogenation catalyst is prepared by the preparation method of the isobutane dehydrogenation catalyst according to any one of claims 5 to 8.

10. The isobutane dehydrogenation catalyst according to claim 9, characterized in that The carrier of the isobutane dehydrogenation catalyst is a cylindrical carrier with a diameter of 3.2 mm ± 0.5 mm, a specific surface area of ​​less than 120 m2 / g, and a pore size of 5 nm-12 nm; In percentage by weight, the isobutane dehydrogenation catalyst comprises: Aluminum oxide 60-90%, chromium oxide 20-24%, sodium oxide 0.5-2%, zirconium oxide 0.5-2%, molybdenum oxide 0.1-0.5%.

Images