Catalyst and process for the production of propane from light hydrocarbons

Abstract

The present application provides a catalyst and a method for converting light hydrocarbons into propane, wherein the catalyst comprises a molecular sieve carrier, a binder component and a modification component, wherein the grain size of the molecular sieve carrier is below 1 μm. The catalyst provided by the present application has a high light hydrocarbon conversion rate and propane selectivity at a lower temperature.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of propane production, in particular to a catalyst and method for producing propane from light hydrocarbons. BACKGROUND

[0002] In recent years, the demand gap for propylene at home and abroad is huge, which has promoted the rapid development of propylene industry and production technology. At present, propylene is mainly produced by the following processes: propane dehydrogenation, catalytic cracking of naphtha, methanol to olefins / propylene (MTO / MTP) and high carbon olefin cracking technology. Considering cost, resources and technology maturity, propane dehydrogenation has become the most competitive process for producing propylene.

[0003] CN201110143584.4 discloses a catalyst for producing propane and high-octane gasoline from butane, specifically hydrogen-type mesoporous silica-alumina zeolite, and the propane yield can reach 25-55%.

[0004] CN110947417A discloses a catalyst for producing propane and gasoline from paraffin, which includes a composite carrier and 0.1-2.0 mass% of rare earth oxides based on the carrier. The composite carrier includes 5-85 mass% of ZSM-5 zeolite, 5-85 mass% of MCM-41 zeolite and 5-40 mass% of alumina. The catalyst is used to convert paraffin under non-hydrogen conditions, has high propane yield, and produces high-octane gasoline blending components as by-products.

[0005] CN111229299A discloses a catalyst for efficient isomerization and aromatization of straight-chain alkanes and a preparation method thereof. The catalyst is a metal-loaded porous silicate (ZSM-5), which can efficiently isomerize or aromatize straight-chain C3-C 12 alkane raw materials to produce high-octane isoparaffins and high-quality gasoline components.

[0006] CN112588314A discloses a catalyst for producing propane from light hydrocarbons and a preparation method thereof. The catalyst is a metal-loaded molecular sieve, which can efficiently convert light hydrocarbon raw materials such as liquefied petroleum gas and naphtha into propane, and the propane selectivity can reach more than 70%.

[0007] The above-mentioned catalysts for producing propane still have the characteristics of low raw material single-pass conversion rate and propane selectivity, especially high dry gas yield. SUMMARY

[0008] In view of the problems existing in the prior art, one of the purposes of the present application is to provide a catalyst for preparing propane from light hydrocarbon. The grain size of the carrier used in the catalyst is below 1 μm. The molecular sieve with small grain size has large specific surface area and short pore channel, which is beneficial to the diffusion of raw material molecules and product molecules and has good stability. In addition, the molecular sieve crystal with small grain size has more defects and more exposed active sites, which is easy to contact with raw material molecules, thus having high activity.

[0009] The second purpose of the present application is to provide a preparation method of the catalyst for preparing propane from light hydrocarbon.

[0010] The third purpose of the present application is to provide a catalyst prepared by the preparation method of the second purpose.

[0011] The fourth purpose of the present application is to provide a method for preparing propane from light hydrocarbon corresponding to the above purposes. In order to achieve one of the above purposes, the technical scheme adopted by the present application is as follows:

[0012] A catalyst for preparing propane from light hydrocarbon, comprising a molecular sieve carrier, a binder component and a modification component, wherein the grain size of the molecular sieve carrier is below 1 μm.

[0013] In some preferred embodiments of the present application, the grain size of the molecular sieve carrier is below 600 nm.

[0014] In some preferred embodiments of the present application, the grain size of the molecular sieve carrier is below 500 nm.

[0015] In some preferred embodiments of the present application, the grain size of the molecular sieve carrier is below 400 nm.

[0016] In some preferred embodiments of the present application, the grain size of the molecular sieve carrier is below 300 nm.

[0017] In some preferred embodiments of the present application, the grain size of the molecular sieve carrier is below 200 nm.

[0018] In some preferred embodiments of the present application, the grain size of the molecular sieve carrier is below 100 nm.

[0019] According to the present application, the grain size of the molecular sieve carrier below 1 μm means that the molecular sieve does not contain grains with grain size above 1 μm, but can contain grains with grain size below 1 μm. Similarly, the grain size of the molecular sieve carrier below 600 nm, the grain size of the molecular sieve carrier below 500 nm and the grain size of the molecular sieve carrier below 400 nm also have similar limiting meanings.

[0020] In some preferred embodiments of the present application, the upper limit of the grain size of the molecular sieve carrier can be any value between 300 nm and 1000 nm, and the lower limit of the grain size of the molecular sieve carrier can be any value between 50 nm and 300 nm. For example, the grain size distribution range of the molecular sieve carrier can be 50 nm to 300 nm, 150 nm to 300 nm, 50 nm to 1000 nm, or 150 nm to 1000 nm, and can also be 100 nm to 300 nm, 100 nm to 500 nm, or 120 nm to 800 nm, etc.

[0021] In some preferred embodiments of the present application, the molecular sieve carrier is derived from a molecular sieve raw powder.

[0022] In some preferred embodiments of the present application, the molecular sieve carrier is derived from a ZSM-5 molecular sieve raw powder.

[0023] In some preferred embodiments of the present application, the molecular sieve carrier is derived from a hydrogen-type ZSM-5 molecular sieve raw powder.

[0024] In some preferred embodiments of the present application, the SiO2 / Al2O3 molar ratio of the molecular sieve raw powder is 5 to 200, preferably 10 to 150, and more preferably 15 to 120.

[0025] In some preferred embodiments of the present application, the total specific surface area of the molecular sieve raw powder is 350 to 450 m 2 / g, and the external specific surface area accounts for 15% to 30% of the total specific surface area.

[0026] According to the present application, the total specific surface area and the external specific surface area of the molecular sieve raw powder are measured by BET and t-plot methods.

[0027] In some preferred embodiments of the present application, the binder component includes γ-alumina and / or silicon oxide.

[0028] In some preferred embodiments of the present application, the modification component includes at least one of zinc oxide, gallium oxide, copper oxide, and silver oxide.

[0029] In some preferred embodiments of the present application, the mass percentage content of the molecular sieve carrier is 60% to 90%, preferably 60% to 80%, based on the total weight of the catalyst.

[0030] In some preferred embodiments of the present application, the mass percentage content of the binder component is 10% to 40%, preferably 15% to 35%, based on the total weight of the catalyst.

[0031] In some preferred embodiments of the present application, the mass percentage of the modification component is 0.1% to 10%, preferably 0.1% to 6%, based on the total weight of the catalyst.

[0032] To achieve the second object, the present application adopts the following technical scheme:

[0033] A preparation method of a catalyst for producing propane from light hydrocarbons, comprising:

[0034] S1. performing a molding treatment on a mixture containing a molecular sieve raw powder, a binder and a kneading agent to obtain a catalyst intermediate;

[0035] S2. introducing a modifier to the catalyst intermediate to obtain a catalyst precursor;

[0036] S3. sequentially performing a drying treatment and a calcination treatment on the catalyst precursor to obtain a catalyst,

[0037] In some preferred embodiments of the present application, the grain size of the molecular sieve raw powder is less than 600 nm.

[0038] In some preferred embodiments of the present application, the grain size of the molecular sieve raw powder is less than 500 nm.

[0039] In some preferred embodiments of the present application, the grain size of the molecular sieve raw powder is less than 400 nm.

[0040] In some preferred embodiments of the present application, the grain size of the molecular sieve raw powder is less than 400 nm.

[0041] According to the present application, the grain size of the molecular sieve raw powder being less than 1 μm means that the molecular sieve does not contain grains with a grain size of more than 1 μm, but can contain grains with a grain size of any value less than 1 μm. Similarly, the grain size of the molecular sieve raw powder being less than 600 nm, the grain size of the molecular sieve raw powder being less than 500 nm and the grain size of the molecular sieve raw powder being less than 400 nm have similar meanings.

[0042] In some preferred embodiments of the present application, the upper limit of the grain size of the molecular sieve raw powder can be any value between 300 nm and 1000 nm, and the lower limit of the grain size of the molecular sieve raw powder can be any value between 20 nm and 300 nm. For example, the grain size distribution range of the molecular sieve raw powder can be 20 nm to 300 nm, 150 nm to 300 nm, 20 nm to 1000 nm or 150 nm to 1000 nm, or 100 nm to 300 nm, 100 nm to 500 nm, 120 nm to 800 nm, etc.

[0043] In some preferred embodiments of the present application, the molecular sieve crude powder is a ZSM-5 molecular sieve crude powder.

[0044] In some preferred embodiments of the present application, the molecular sieve crude powder is a hydrogen-type ZSM-5 molecular sieve crude powder.

[0045] In some preferred embodiments of the present application, the SiO2 / Al2O3 molar ratio of the molecular sieve crude powder is 5-200, preferably 10-150; the total specific surface area is 350-450 m2 / g, and the external specific surface area accounts for 15%-30% of the total specific surface area. 2

[0046] In some preferred embodiments of the present application, the binder is selected from at least one of pseudo-boehmite, boehmite, silica sol, kaolin and amorphous silica-alumina.

[0047] In some preferred embodiments of the present application, the kneading agent comprises nitric acid.

[0048] According to the present application, the nitric acid is chemically pure nitric acid, i.e. nitric acid with a mass concentration within 50-70%.

[0049] In some preferred embodiments of the present application, the modifier is selected from at least one of nitrate, sulfate and chloride of a modified metal, the modified metal being selected from at least one of zinc, gallium, copper and silver.

[0050] According to the present application, the modifier is selected from at least one of zinc nitrate, cerium nitrate and copper nitrate, preferably comprising zinc nitrate and copper nitrate. When the modifier comprises both zinc nitrate and copper nitrate, the mass ratio of zinc nitrate to copper nitrate is 1:(0.5-1.5), preferably 1:(0.5-1).

[0051] According to the present application, the forming treatment comprises kneading-extrusion forming followed by drying and calcination. The drying can be air drying under natural conditions. The calcination can be performed at 500-550°C for 3-10 hours in an air atmosphere.

[0052] In some preferred embodiments of the present application, in step S1, the mass ratio of the molecular sieve crude powder to the binder is 100:(1-50), preferably 100:(5-40), more preferably 100:(10-30).

[0053] In some preferred embodiments of the present application, in step S2, the mass ratio of the catalyst intermediate to the modifier is 100:(3-25), preferably 100:(5-20). ​

[0054] According to the present application, in step S2, the modifier can be introduced into the catalyst intermediate by ion exchange and / or impregnation. Both ion exchange and impregnation are commonly used ways to introduce the modifier in the art, and the present application is not intended to be limited in this respect, as long as the modifier can be introduced into the catalyst intermediate, both of which can be applied to the present application.

[0055] In some preferred embodiments of the present application, in step S3, the drying treatment is performed under the conditions of a temperature of 80-120°C, preferably 100-120°C, and a time of 1-48h, preferably 5-15h.

[0056] In some preferred embodiments of the present application, in step S3, the calcination treatment is performed under the conditions of a temperature of 400-700°C, preferably 500-550°C, and a time of 1-48h, preferably 1-10h, more preferably 2-6h.

[0057] To achieve the third object, the present application adopts the following technical scheme:

[0058] A catalyst prepared by the preparation method of any one of the above embodiments.

[0059] In some preferred embodiments of the present application, the catalyst comprises a molecular sieve carrier, a binder component and a modified component, wherein the grain size of the molecular sieve carrier is below 1 μm.

[0060] In some preferred embodiments of the present application, the grain size of the molecular sieve carrier is below 600 nm.

[0061] In some preferred embodiments of the present application, the grain size of the molecular sieve carrier is below 500 nm.

[0062] In some preferred embodiments of the present application, the grain size of the molecular sieve carrier is below 400 nm.

[0063] According to the present application, the grain size of the molecular sieve carrier below 1 μm means that the molecular sieve does not contain grains with a grain size above 1 μm, but can contain grains with a grain size below 1 μm at any value. Similarly, the grain size of the molecular sieve carrier below 600 nm, the grain size of the molecular sieve carrier below 500 nm and the grain size of the molecular sieve carrier below 400 nm also have similar limiting meanings.

[0064] In some preferred embodiments of the present application, the upper limit of the grain size of the molecular sieve carrier can be any value between 300 nm and 1000 nm, and the lower limit of the grain size of the molecular sieve carrier can be any value between 50 nm and 300 nm. For example, the grain size distribution range of the molecular sieve carrier can be 50 nm to 300 nm, 150 nm to 300 nm, 50 nm to 1000 nm, or 150 nm to 1000 nm, and can also be 100 nm to 300 nm, 100 nm to 500 nm, or 120 nm to 800 nm, etc.

[0065] In some preferred embodiments of the present application, the molecular sieve carrier is derived from the molecular sieve raw powder.

[0066] In some preferred embodiments of the present application, the molecular sieve carrier is derived from the ZSM-5 molecular sieve raw powder.

[0067] In some preferred embodiments of the present application, the molecular sieve carrier is derived from the hydrogen-type ZSM-5 molecular sieve raw powder.

[0068] In some preferred embodiments of the present application, the binding component is derived from the binder.

[0069] In some preferred embodiments of the present application, the modification component is derived from the modifier.

[0070] In some preferred embodiments of the present application, the mass percentage content of the molecular sieve carrier is 40% to 80%, preferably 60% to 80%, based on the total weight of the catalyst.

[0071] In some preferred embodiments of the present application, the mass percentage content of the binding component is 10% to 30%, preferably 15% to 25%, based on the total weight of the catalyst.

[0072] In some preferred embodiments of the present application, the mass percentage content of the modification component is 0.1% to 10%, preferably 0.1% to 5%, based on the total weight of the catalyst.

[0073] To achieve the fourth purpose described above, the technical solution adopted by the present application is as follows:

[0074] A method for producing propane from light hydrocarbons, comprising: contacting a stream containing light hydrocarbons with the catalyst of any one of the above embodiments, wherein the light hydrocarbons are selected from at least one of C4-C6 alkanes.

[0075] In some preferred embodiments of the present application, the light hydrocarbons are butane.

[0076] According to the present application, the butane can be n-butane or isobutane.

[0077] In some preferred embodiments of the present application, the contacting is carried out at a temperature of 200-500°C, preferably 250-450°C; a pressure of 0.2-6 MPa, preferably 0.5-3 MPa; a mass space velocity of 0.1-2 h-1, preferably 0.2-1 h-1. -1 ~2h -1 .

[0078] According to the present application, the method can be carried out in a fixed bed reactor.

[0079] According to the present application, the contacting of the stream comprising light hydrocarbons with the catalyst of any one of the above embodiments can produce a product comprising propane and aromatic hydrocarbons.

[0080] In the present application, the term "light hydrocarbons" refers to C4-C6 alkanes.

[0081] In the present application, the Na2O content in the as-synthesized molecular sieve is less than 0.15 wt%.

[0082] In the present application, the Na2O content in the pseudoboehmite is less than 0.15 wt%.

[0083] The present application has at least the following advantages:

[0084] Firstly, the catalyst provided by the present application has a high catalytic activity and selectivity, and can convert alkanes, especially butane, at a conversion rate of more than 70% and a selectivity of more than 75% for the target product propane at a relatively low temperature, for example, 360°C.

[0085] Secondly, the catalyst provided by the present application can maintain a butane conversion rate of more than 50% after 800 hours of reaction under suitable reaction conditions. BRIEF DESCRIPTION OF DRAWINGS

[0086] Figure 1 is a scanning electron microscope picture of the catalyst prepared in Example 2. DETAILED DESCRIPTION

[0087] The present application is described in detail below by way of examples, but the scope of protection of the present application is not limited to the following description.

[0088] The specific conditions not specified in the examples are carried out according to the conventional conditions or the conditions recommended by the manufacturer. The reagents or instruments not specified by the manufacturer are conventional products that can be obtained by market purchase.

[0089] In the following embodiments, the nitric acid used is chemical pure nitric acid with a mass concentration of 65%.

[0090] In the following embodiments, the composition of the catalyst was tested by elemental analysis.

[0091] Example 1

[0092] 200.0 g of hydrogen-form ZSM-5 molecular sieve powder with a SiO2 / Al2O3 molar ratio of 15 (particle size observed by scanning electron microscopy is 300 nm~400 nm, and the total specific surface area measured by BET is 365 g / m²) was tested. 2 The external specific surface area is 70 g / m². 2 The mixture was thoroughly mixed with 40 g of pseudoboehmite containing less than 0.15 wt% Na2O. A solution was prepared using 4 ml of chemically pure nitric acid and 80 ml of water. This solution was added to the mixture of ZSM-5 molecular sieve and pseudoboehmite, kneaded and extruded into strips, dried, and then dried overnight at 110°C. Finally, it was calcined at 520°C for 6 hours to obtain the catalyst intermediate.

[0093] A solution was prepared using 15 g of chemically pure zinc nitrate and 50 ml of water. This solution was added to 80 g of a pre-formed catalyst intermediate, and then dried at 110 °C for 10 hours and calcined at 550 °C for 6 hours. Catalyst A was obtained with a weight ratio of zinc oxide / hydrogen-type ZSM-5 molecular sieve / alumina = 1.3 / 76.5 / 21.

[0094] Example 2

[0095] 160.0 g of hydrogen-form ZSM-5 molecular sieve powder with a SiO2 / Al2O3 molar ratio of 100 (particle size observed by scanning electron microscopy is 80 nm~300 nm, and the total specific surface area measured by BET is 402 g / m²). 2 The external specific surface area is 83 g / m². 2 The mixture was thoroughly mixed with 46.1 g of pseudoboehmite with a Na2O content of less than 0.15 wt%. A solution was prepared by mixing 4 ml of chemically pure nitric acid and 80 ml of water. This solution was then added to the mixture of ZSM-5 molecular sieve and pseudoboehmite, mixed thoroughly, kneaded and extruded into strips, dried, and then dried overnight at 110°C and calcined at 550°C for 3 hours.

[0096] A solution was prepared using 12 g of chemically pure zinc nitrate, 8 g of copper nitrate, and 60 ml of water. 30 ml of this solution was added to 50 g of a pre-formed support, and the mixture was then dried at 110°C for 10 hours and calcined at 550°C for 6 hours. Catalyst B was obtained with a weight ratio of zinc oxide / copper oxide / hydrogen-type ZSM-5 molecular sieve / alumina = 1.7 / 1.4 / 67 / 30.

[0097] Example 3

[0098] The difference between this example and Example 1 is that the ZSM-5 molecular sieve powder used has a SiO2 / Al2O3molar ratio of 120, a particle size of 300-400 nm as observed by scanning electron microscopy, and a total specific surface area of 394 g / m2and an external specific surface area of 71 g / m2as measured by BET. 2 2 .

[0099] Catalyst C was prepared under the same conditions as Example 1.

[0100] Example 4

[0101] The difference between this example and Example 1 is that the ZSM-5 molecular sieve powder used has a SiO2 / Al2O3molar ratio of 85, a particle size of 800-1000 nm as observed by scanning electron microscopy, and a total specific surface area of 366 g / m2and an external specific surface area of 59 g / m2as measured by BET. 2 2 .

[0102] Catalyst D was prepared under the same conditions as Example 1.

[0103] Example 5

[0104] The difference between this example and Example 1 is that the ZSM-5 molecular sieve powder used has a SiO2 / Al2O3molar ratio of 15, a particle size of 700-800 nm as observed by scanning electron microscopy, and a total specific surface area of 374 g / m2and an external specific surface area of 89 g / m2as measured by BET. 2 2 .

[0105] Catalyst E was prepared under the same conditions as Example 1.

[0106] Example 6

[0107] The difference between this example and Example 1 is that the ZSM-5 molecular sieve powder used has a SiO2 / Al2O3molar ratio of 45, a particle size of 50-100 nm as observed by scanning electron microscopy, and a total specific surface area of 416 g / m2and an external specific surface area of 109 g / m2as measured by BET. 2 2 .

[0108] Catalyst F was prepared under the same conditions as Example 1.

[0109] Example 7

[0110] The same carrier and binder as in Example 2 were used.

[0111] ​​​​A solution was prepared from 8 g of chemically pure silver nitrate and 60 ml of water. 30 ml of the solution was added to 50 g of the shaped carrier, which was then dried at 110°C for 10 hours and calcined at 550°C for 6 hours. Catalyst G was prepared with a weight ratio of silver oxide / hydrogen-type ZSM-5 molecular sieve / alumina = 1.4 / 67 / 30.

[0112] Example 8

[0113] The carrier and the binder used were the same as in Example 2.

[0114] A solution was prepared from 11 g of chemically pure gallium nitrate and 60 ml of water. 20 ml of the solution was added to 50 g of the shaped carrier, which was then dried at 110°C for 10 hours and calcined at 550°C for 6 hours. Catalyst H was prepared with a weight ratio of gallium oxide / hydrogen-type ZSM-5 molecular sieve / alumina = 2.2 / 67 / 30.

[0115] Comparative Example 1

[0116] The difference between this example and Example 1 is that the ZSM-5 molecular sieve powder used has a SiO2 / Al2O3 molar ratio of 80, a particle size of 2000 nm to 3000 nm as observed by scanning electron microscopy, and a total specific surface area of 340 m2 / g and an external specific surface area of 35 m2 / g as measured by BET. 2 2

[0117] Catalyst J was prepared under the same conditions as in Example 1.

[0118] Test Example 1

[0119] The activity evaluation was carried out under the conditions of 1 MPa, a temperature of 360°C, and a mass space velocity of n-butane of 1 h -1 The results of the reaction after 5 hours of reaction of the catalyst are shown in Table 1. Among them,

[0120] The n-butane conversion rate = (mass of the raw material butane - mass of the product butane) / mass of the raw material butane;

[0121] The propane selectivity = mass of the product propane / butane conversion rate;

[0122] The dry gas selectivity = mass of the dry gas / butane conversion rate.

[0123] Table 1

[0124]

[0125] Note: In the above table, the dry gas refers to methane and ethane.

[0126] ​​It should be noted that the foregoing examples have been provided merely for the purposes of illustration and are not intended to limit the application in any way. Descriptions and examples of materials and processes of the application are intended to be illustrative not limiting. Any modifications of the application and other applications of the application will occur to those skilled in the art to which the application pertains and many options for modification of the application will suggest themselves. The application lies in the broadest aspects of the art, and there are many alternatives for the application of the application.

Claims

1. A catalyst for the production of propane from light hydrocarbons, comprising: A molecular sieve carrier, a binding component and a modifying component, wherein the grain size of the molecular sieve carrier is below 1 μm; The molecular sieve carrier is derived from ZSM-5 molecular sieve raw powder; The SiO2 / Al2O3 molar ratio of the molecular sieve crude powder is 5-200, and the total specific surface area is 350-450 m2 / g, and the external specific surface area accounts for 15%-30% of the total specific surface area. 2 / g, and the external specific surface area accounts for 15%-30% of the total specific surface area. The binding component comprises γ-alumina and / or silicon oxide; The modifying component comprises at least one of zinc oxide, gallium oxide, copper oxide and silver oxide; The mass percentage of the molecular sieve carrier is 60% to 90% based on the total weight of the catalyst; the mass percentage of the binding component is 10% to 40%; and the mass percentage of the modifying component is 0.1% to 10%.

2. The catalyst according to claim 1, characterized in that, The molecular sieve carrier is derived from hydrogen ZSM-5 molecular sieve raw powder; and / or The SiO2 / Al2O3 molar ratio of the molecular sieve raw powder is 10 to 150; and / or The grain size of the molecular sieve carrier is below 600 nm.

3. The catalyst of claim 2, wherein The SiO2 / Al2O3 molar ratio of the molecular sieve raw powder is 15 to 120; and / or The grain size of the molecular sieve carrier is below 500 nm.

4. Catalyst according to any one of claims 1 to 3, characterized in that The mass percentage of the molecular sieve carrier is 60% to 80% based on the total weight of the catalyst; and / or the mass percentage of the binding component is 15% to 35%; and / or the mass percentage of the modifying component is 0.1% to 6%.

5. A preparation method of a catalyst for light hydrocarbon to propane, comprising: S1. performing a molding treatment on a mixture containing molecular sieve raw powder, a binding agent and a kneading agent to obtain a catalyst intermediate; S2. introducing a modifying agent on the catalyst intermediate to obtain a catalyst precursor; S3. sequentially performing a drying treatment and a calcination treatment on the catalyst precursor to obtain a catalyst; The grain size of the molecular sieve raw powder is below 1 μm; The molecular sieve raw powder is ZSM-5 molecular sieve raw powder; The SiO2 / Al2O3 molar ratio of the molecular sieve crude powder is 5-200; the total specific surface area is 350-450 m2 / g, and the external specific surface area accounts for 15%-30% of the total specific surface area. 2 / g, and the external specific surface area accounts for 15%-30% of the total specific surface area. The binding agent is selected from at least one of pseudo-boehmite, boehmite, silica sol, kaolin and amorphous silicon aluminum; The modifying agent is selected from at least one of nitrate, sulfate and chloride of a modifying metal, the modifying metal being selected from at least one of zinc, gallium, copper and silver; In step S1, the mass ratio of the molecular sieve raw powder to the binding agent is 100:(5 to 40); In step S2, the mass ratio of the catalyst intermediate to the modifying agent is 100:(3 to 25).

6. The production method according to claim 5, wherein The molecular sieve raw powder is hydrogen ZSM-5 molecular sieve raw powder; and / or The grain size of the molecular sieve raw powder is below 600 nm; and / or The SiO2 / Al2O3 molar ratio of the molecular sieve raw powder is 10 to 150; and / or The kneading agent comprises nitric acid.

7. The production method according to claim 6, wherein The grain size of the molecular sieve raw powder is below 500 nm.

8. The production method according to any one of claims 5 to 7, characterized by, In step S1, the mass ratio of the molecular sieve raw powder to the binding agent is 100:(10 to 30); and / or in step S2, the mass ratio of the catalyst intermediate to the modifying agent is 100:(5 to 20).

9. The production method according to any one of claims 5 to 7, characterized by, In step S3, the drying treatment is performed at a temperature of 80-120°C for 1-48 hours, and / or the calcination treatment is performed at a temperature of 400-700°C for 1-48 hours.

10. The method of claim 9, wherein, In step S3, the drying treatment is performed at a temperature of 100-120°C for 5-15 hours, and / or the calcination treatment is performed at a temperature of 500-550°C for 1-10 hours.

11. The method of claim 10, wherein, In step S3, the calcination treatment is performed for 2-6 hours.

12. A catalyst prepared by the production method of any one of claims 5-11.

13. A process for making propane from light hydrocarbons comprising: contacting a stream comprising light hydrocarbons with the catalyst of any one of claims 1-4 or the catalyst of claim 12, wherein the light hydrocarbons are selected from at least one of C4-C6 alkanes.

14. The method of claim 13, wherein, The light hydrocarbons are butane.

15. The method according to claim 13 or 14, characterized in that, The conditions of the contact include: temperature 200℃-500℃; pressure 0.2MPa-6MPa; mass space velocity 0.1h -1 ~2h -1 .

16. The method of claim 15, wherein, The contacting is performed at a temperature of 250-450°C and a pressure of 0.5-3 MPa.

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