Catalysts for processing light hydrocarbons and their preparation and regeneration methods; methods for processing light hydrocarbons

Abstract

The present invention relates to the field of catalyst technology, and in particular to a catalyst for processing light hydrocarbons, a preparation method thereof, a regeneration method, and a method for processing light hydrocarbons. The catalyst includes a composite carrier, and a sulfate radical and an active component loaded on the composite carrier, wherein the active component includes a rare earth element and / or a Group VA element; based on the total weight of the composite carrier, the composite carrier contains 10-50wt% of hydrogen-type ZSM-5 zeolite, 5-40wt% of zirconium oxide, and 10-85wt% of aluminum oxide. The catalyst has high catalytic stability and regeneration performance, and the catalyst provided by the present invention is used for processing light hydrocarbons, especially for processing light naphtha, and can produce aromatics and by-product low-carbon olefins, and obtain a higher aromatics yield and low-carbon olefin yield, and at the same time, the catalyst has strong anti-carbon deposition ability and a long single-pass reaction cycle.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts, and in particular to a catalyst for processing light hydrocarbons, a preparation method and a regeneration method thereof, and a method for processing light hydrocarbons. Background Art

[0002] Light naphtha is generally a mixture of C4 to C7 low-carbon hydrocarbons produced as a by-product in the processing of petroleum and coal. Its main sources are the following: C4 to C7 from catalytic cracking, hydrocracking and coking units. 4+ Components, cracking C of ethylene cracking unit 5+ Components, catalytic reforming and aromatics extraction combined unit top oil, raffinate oil and other fractions, due to the very high vapor pressure of light hydrocarbon components, with the new gasoline standard further restricting the vapor pressure, the amount of this component is gradually restricted, and it is urgent to find new ways to use it. At the same time, with the development of my country's oil refining industry technology and the continuous expansion of crude oil processing scale, the processing depth of crude oil is increasing, and more and more light hydrocarbon resources mainly C4~C7 are produced from refineries. Converting them into high-value chemicals such as aromatics and low-carbon olefins will greatly improve the benefits of light hydrocarbon utilization, which is of great significance to the transformation of refining enterprises to chemical industry.

[0003] In recent years, various studies have been conducted around the utilization of light hydrocarbons at home and abroad, among which the aromatization technology of light hydrocarbons has developed rapidly. The light hydrocarbon aromatization technologies that have been developed include Japan's Alpha Process, the Cyclar process jointly developed by UOP / BP, and Japan's Z-forming process. The light hydrocarbon aromatization developed in China has also achieved extensive industrial applications. Against this background, there are also related research reports on the simultaneous production of aromatics and light olefins using light hydrocarbons as raw materials.

[0004] CN1065901C first proposed a method for simultaneously converting non-aromatic hydrocarbons into aromatic hydrocarbons and olefins. It used a zeolite catalyst modified with silicon, boron, phosphorus, and alkaline earth metals and specially post-treated to reduce the coking rate while increasing the yield of aromatic hydrocarbons and light olefins in the aromatization process. At the same time, in terms of process research, the partial pressure of the reactants was reduced by adding an inert medium, further increasing the yield of light olefins.

[0005] CN1504541A discloses a catalyst and application for catalytic cracking of hydrocarbons to produce olefins and co-produce aromatics. It adopts a molecular sieve catalyst with a pore size of 0.45-0.7nm modified by phosphorus, alkaline earth metals, lithium and rare earth, and appropriately promotes the occurrence of aromatization reaction in the catalytic cracking reaction of naphtha, gasoline, diesel and other fractions, thereby producing aromatics (the yield of ethylene + propylene + aromatics is 60% to 80%) while producing olefins.

[0006] CN1370216A discloses a method of 4+The method for catalytically producing light olefins from naphtha raw materials is to prepare phosphorus-containing ZSM-5 molecular sieves and ZSM-11 molecular sieves with inert matrix materials such as silicon oxide and clay, and to reduce the occurrence of side reactions such as hydrogen transfer as much as possible in a water vapor environment, so that C4~C 12 The straight run and cracking naphtha materials of olefins or alkanes are directly converted into more valuable light olefins such as ethylene and propylene and aromatics such as toluene and xylene.

[0007] CN100509714C uses a silicon-modified catalyst to carry out catalytic conversion of C4 olefins to produce ethylene, propylene and aromatics, which can obtain higher ethylene and propylene yields, and the generated aromatics contain more p-xylene.

[0008] The above-mentioned routes for simultaneously producing aromatics and light olefins using light hydrocarbons as raw materials mostly rely on the light hydrocarbon aromatization technology platform. Benefiting from the mild operating conditions compared to the catalytic cracking process, light hydrocarbon aromatization has outstanding advantages such as low coke yield and small processing loss. However, current research mainly focuses on fixed-bed catalysts and process stages, and there are problems such as low yield of light olefins, severe catalyst carbon deposition, and rapid deactivation. Summary of the invention

[0009] The purpose of the present invention is to overcome the problems of low yield of light olefins, serious catalyst carbon deposition, rapid catalyst deactivation, poor catalyst regeneration stability, etc. in the existing light hydrocarbon processing process, and to provide a catalyst for processing light hydrocarbons, a preparation method and a regeneration method thereof, and a method for processing light hydrocarbons. The catalyst is used to process light hydrocarbons, and a higher yield of aromatics and light olefins can be obtained at the same time.

[0010] In order to achieve the above-mentioned object, the first aspect of the present invention provides a catalyst for processing light hydrocarbons, the catalyst comprising a composite carrier, and sulfate and an active component supported on the composite carrier, wherein the active component comprises a rare earth element and / or a Group VA element;

[0011] The composite support contains 10-50 wt% of hydrogen-type ZSM-5 zeolite, 5-40 wt% of zirconium oxide and 10-85 wt% of aluminum oxide, based on the total weight of the composite support.

[0012] A second aspect of the present invention provides a method for preparing a catalyst for processing light hydrocarbons, the method comprising the following steps:

[0013] (1) preparing a composite powder containing hydrogen-type ZSM-5 zeolite and zirconium hydroxide by a coprecipitation method;

[0014] (2) mixing the composite powder and aluminum sol to obtain a slurry; and forming the slurry into balls by dropping in an oil-ammonia column, and drying the obtained wet balls to obtain dry balls, and then immersing the dry balls in a sulfuric acid solution, and then drying and calcining to obtain a sulfate-loaded composite carrier;

[0015] (3) The composite carrier is immersed in a solution containing a soluble rare earth compound and / or a soluble Group VA element compound, and then dried and calcined to obtain a catalyst loaded with sulfate radicals and active components.

[0016] The third aspect of the present invention provides a method for regenerating a catalyst for processing light hydrocarbons, the method comprising: regenerating a deactivated catalyst and an oxygen-containing gas in the presence of an inert gas to obtain a regenerated catalyst; wherein the deactivated catalyst is a catalyst that reacts continuously for 120 hours, and the catalyst is the catalyst provided in the first aspect, or a catalyst obtained by the method provided in the second aspect.

[0017] The fourth aspect of the present invention provides a method for processing light hydrocarbons, which comprises: contacting and reacting light hydrocarbons and a catalyst in the presence of a non-hydrogen gas; the catalyst is the catalyst provided in the first aspect, or a catalyst prepared by the method provided in the second aspect.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] (1) The catalyst provided by the present invention comprises a composite carrier and sulfate and an active component supported on the composite carrier. By limiting the composite carrier to contain a specific component at a specific content, and then combining the sulfate and the active component, the catalytic activity of the catalyst can be effectively improved. In particular, the content of the active component is further limited to further improve the catalytic activity of the catalyst. At the same time, the catalyst provided by the present invention has high catalytic stability and regeneration performance.

[0020] (2) The preparation method of the catalyst provided by the present invention is simple and convenient for industrial production;

[0021] (3) The catalyst provided by the present invention is used to process light hydrocarbons, especially light naphtha, to produce aromatics and by-product low-carbon olefins, and to achieve a higher aromatics yield and low-carbon olefin yield; at the same time, the catalyst has a strong ability to resist carbon deposition and a long single-pass reaction cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 TEM images of the hydrogen-type ZSM-5 zeolite (SiO2 / Al2O3 molar ratio of 150) and the composite support A1 in Example 1, wherein a is a TEM image of the hydrogen-type ZSM-5 zeolite (SiO2 / Al2O3 molar ratio of 150), and b is a TEM image of the composite support A1;

[0023] Figure 2 It is a pore size distribution curve diagram of the catalysts (S1-S4, S9-S10 and DS1) prepared in Examples 1-4, Examples 9-10 and Comparative Example 1. DETAILED DESCRIPTION

[0024] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0025] The first aspect of the present invention provides a catalyst for processing light hydrocarbons, the catalyst comprising a composite carrier, and sulfate and an active component supported on the composite carrier, the active component comprising a rare earth element and / or a Group VA element;

[0026] The composite support contains 10-50 wt% of hydrogen-type ZSM-5 zeolite, 5-40 wt% of zirconium oxide and 10-85 wt% of aluminum oxide, based on the total weight of the composite support.

[0027] The inventors of the present invention have found through research that the catalyst provided by the present invention can effectively improve the catalytic activity of the catalyst by limiting the specific components and specific content of the composite carrier, combined with the specific content of the active component. The catalyst is used for processing light hydrocarbons, especially for the aromatization reaction of light naphtha, and a higher aromatics yield and low-carbon olefin yield can be obtained at the same time, and the catalyst's resistance to carbon deposition can be improved, thereby extending the catalyst's single-pass reaction cycle.

[0028] Specifically, the hydrogen-type ZSM-5 zeolite in the composite carrier has a strong acidity, which can activate the light naphtha component into positive carbon ions, part of which is further converted into aromatic components, and part of which is converted into ethylene and propylene. In particular, the hydrogen-type ZSM-5 zeolite is modified (i.e., weak base multi-level pore treatment), so that the proportion of mesopores and micropores is significantly increased while maintaining the crystalline phase intact and the structure stable, so that the accessibility of the zeolite acidic site is greatly improved, thereby increasing the conversion rate of the light naphtha component. At the same time, the diffusion efficiency of low-carbon olefins is improved, and they can quickly break away from the reaction after generation. The reaction system is improved, secondary reactions such as hydrogen transfer are reduced, and the yield of light olefins is significantly increased; the zirconium oxide in the composite carrier forms a rich mesoporous structure on the surface of the hydrogen-type ZSM-5 zeolite, which accelerates the diffusion of reactants and products, further inhibits the occurrence of bimolecular reactions such as hydrogen transfer that consume light olefins, and further improves the selectivity of light olefins; the rare earth elements in the active components are beneficial to the dehydrogenation activation of light alkane molecules in the initial stage of the reaction; the VA group elements in the active components can effectively reduce catalyst carbon deposition, extend the catalyst single-pass reaction time, and improve the regeneration performance, thereby increasing the service life of the catalyst.

[0029] In some embodiments of the present invention, preferably, based on the total weight of the composite carrier, the composite carrier contains 20-50wt% hydrogen-type ZSM-5 zeolite, 10-40wt% zirconium oxide and 10-70wt% alumina; further preferably, based on the total weight of the composite carrier, the composite carrier contains 20-50wt% hydrogen-type ZSM-5 zeolite, 10-40wt% zirconium oxide and 40-50wt% alumina. The use of the preferred conditions is more conducive to improving the structural fit between the two main components of the composite carrier, forming a mesoporous structure, significantly increasing the ratio of mesopores and micropores, and significantly improving the catalyst performance.

[0030] In some embodiments of the present invention, preferably, in the hydrogen ZSM-5 zeolite, the SiO2 / Al2O3 molar ratio is 100-300:1, for example, 100:1, 120:1, 150:1, 180:1, 200:1, 230:1, 250:1, 300:1, and any value in the range consisting of any two values, preferably 120-250:1.

[0031] In some embodiments of the present invention, preferably, the total specific surface area of ​​the hydrogen-type ZSM-5 zeolite is 300-480 m 2 / g, preferably 350-440m 2 / g; mesopore specific surface area is 20-35m 2 / g, preferably 20-30m 2The preferred conditions are favorable for improving the accessibility of the acid sites of the hydrogen-type ZSM-5 zeolite, thereby increasing the conversion rate of light hydrocarbon (especially light naphtha) components and the yield of light olefins.

[0032] In the present invention, unless otherwise specified, the specific surface area parameter is measured using the ASTM D4365 method.

[0033] In some embodiments of the present invention, preferably, the crystal form of the aluminum oxide is selected from at least one of α-Al2O3, β-Al2O3 and γ-Al2O3, preferably γ-Al2O3.

[0034] In some embodiments of the present invention, preferably, based on the total weight of the composite carrier, the sulfate content calculated as S is 0.1-15wt%, for example, 0.1wt%, 1wt%, 2wt%, 4wt%, 6wt%, 8wt%, 10wt%, 12wt%, 15wt%, and any value in the range consisting of any two values, preferably 1-12wt%.

[0035] In the present invention, unless otherwise specified, the active component including rare earth elements and / or Group VA elements means that the active component may contain rare earth elements or Group VA elements, or contain rare earth elements and Group VA elements at the same time.

[0036] In some embodiments of the present invention, preferably, based on the total weight of the composite carrier, the rare earth element content in terms of single substance is 0.1-5wt%, for example, 0.1wt%, 0.5wt%, 1wt%, 1.5wt%, 2wt%, 2.5wt%, 3wt%, 4wt%, 5wt%, and any value in the range of any two values, preferably 0.1-3wt%; the VA group element content in terms of oxide is 0.1-10wt%, for example, 0.1wt%, 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, and any value in the range of any two values ​​is preferably 1-8wt%. In the present invention, by regulating the content of rare earth elements and VA group elements, it is more conducive to improving the service life of the catalyst, thereby improving the yield of aromatics and low-carbon olefins.

[0037] In some embodiments of the present invention, preferably, the rare earth element is selected from lanthanum and / or cerium, preferably lanthanum, but the present invention is not limited thereto.

[0038] In some embodiments of the present invention, preferably, the Group VA element is selected from phosphorus and / or antimony, preferably phosphorus, but the present invention is not limited thereto.

[0039] In the present invention, the light hydrocarbon has a wide selection range. Preferably, the light hydrocarbon is a C4-C7 mixed hydrocarbon, preferably a C4-C7 light naphtha. In the present invention, the light naphtha is a C4-C7 low-carbon hydrocarbon mixture; the present invention does not limit the source of the light naphtha.

[0040] According to the present invention, preferably, the particle size of the composite carrier is 1.2-2.5 mm, for example, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2 mm, 2.2 mm, 2.5 mm, and any value in the range consisting of any two values, preferably 1.4-2.2 mm.

[0041] In some embodiments of the present invention, preferably, the composite carrier is spherical in shape, and the diameter of the composite carrier is 1.2-2.5 mm, preferably 1.4-2.2 mm.

[0042] According to the present invention, preferably, the total specific surface area of ​​the catalyst is 280-450m 2 / g, preferably 350-440m 2 / g; mesopore specific surface area is 40-200m 2 / g, preferably 40-150m 2 / g; mesopore volume is 0.1-0.5cm 3 / g, preferably 0.1-0.15cm 3 / g; the most probable pore diameter is 26-50nm, preferably 26-32nm.

[0043] In the present invention, unless otherwise specified, the particle size parameter is measured using the ASTM D4513-11 method; the mesopore volume parameter is measured using ASTM D4365; and the most probable pore diameter parameter is measured using ASTM D4641-17.

[0044] According to a particularly preferred embodiment of the present invention, a catalyst for processing light naphtha comprises a composite carrier, and sulfate and an active component supported on the composite carrier, wherein the active component comprises a rare earth element and a Group VA element;

[0045] Based on the total weight of the composite support, the composite support contains 20-50wt% of hydrogen-type ZSM-5 zeolite, 10-40wt% of zirconium oxide and 40-50wt% of aluminum oxide;

[0046] Based on the total weight of the composite carrier, the sulfate content calculated as S is 1-12 wt %, the rare earth element content calculated as a single substance is 0.1-3 wt %, and the Group VA element content calculated as an oxide is 1-8 wt %.

[0047] A second aspect of the present invention provides a method for preparing a catalyst for processing light hydrocarbons, the method comprising the following steps:

[0048] (1) preparing a composite powder containing hydrogen-type ZSM-5 zeolite and zirconium hydroxide by a coprecipitation method;

[0049] (2) mixing the composite powder and aluminum sol to obtain a slurry; and forming the slurry into balls by dropping in an oil-ammonia column, and drying the obtained wet balls to obtain dry balls, and then immersing the dry balls in a sulfuric acid solution, and then drying and calcining to obtain a sulfate-loaded composite carrier;

[0050] (3) The composite carrier is immersed in a solution containing a soluble rare earth compound and / or a soluble Group VA element compound, and then dried and calcined to obtain a catalyst loaded with sulfate radicals and active components.

[0051] In the present invention, unless otherwise specified, the soluble compound refers to a compound that is easily soluble in water, or that is easily soluble in water under the action of an auxiliary agent.

[0052] In some embodiments of the present invention, preferably, in step (1), the composite powder is prepared by the following method: mixing the hydrogen ZSM-5 zeolite and a soluble zirconium compound solution, and adding ammonia water to the mixture until the pH value of the solution is 7-10, and then filtering and drying; wherein the drying conditions are preferably a temperature of 30-120°C and a time of 2-6h.

[0053] In some embodiments of the present invention, preferably, the weight ratio of the hydrogen ZSM-5 zeolite and the soluble zirconium compound solution is 1:0.1-10, for example, 1:0.1, 1:0.2, 1:0.5: 1:1, 1:2, 1:3, 1:4, 1:5, 1:8, 1:10, and any value in the range composed of any two numerical values, preferably 1:0.2-5, wherein the soluble zirconium compound solution is calculated as soluble zirconium compound.

[0054] In some embodiments of the present invention, preferably, in the soluble zirconium compound solution, the concentration of the soluble zirconium compound is 1-50wt%, for example, 1wt%, 2wt%, 5wt%, 10wt%, 15wt%, 20wt%, 30wt%, 40wt%, 50wt%, and any value in the range consisting of any two values, preferably 2-40wt%.

[0055] In the present invention, there is a wide selection range for the types of the soluble zirconium compound, and the soluble zirconium compound includes but is not limited to zirconium oxychloride and zirconium nitrate, and is preferably zirconium oxychloride.

[0056] In the present invention, the ammonia water precipitates the soluble zirconium compound (zirconium oxychloride) to form zirconium hydroxide. Preferably, the concentration of ammonia in the ammonia water is 2-15wt%, for example, 2wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 15wt%, and any value in the range of any two values, preferably 4-10wt%.

[0057] In some embodiments of the present invention, preferably, the content of aluminum oxide in the aluminum sol is 8-16wt%, for example, 8wt%, 9wt%, 10wt%, 11wt%, 12wt%, 14wt%, 16wt%, and any value in the range of any two values ​​is preferably 8-12wt%. In the present invention, the content of aluminum oxide in the aluminum sol is crucial to the drop ball forming effect of the aluminum sol. If the content is too low, a spherical carrier cannot be obtained, and if the content is too high, it cannot flow and complete the drop ball forming process.

[0058] In the present invention, the source of the aluminum sol has a wide selection range, as long as the content of aluminum oxide in the aluminum sol meets the above definition. Preferably, the aluminum sol is obtained by peptizing an aluminum source with an acid solution.

[0059] In some embodiments of the present invention, preferably, the weight ratio of the aluminum source to the acid solution is 1:0.02-0.2, for example, 1:0.02, 1:0.04, 1:0.06, 1:0.08, 1:0.1, 1:0.12, 1:0.15, 1:0.2, and any value in the range consisting of any two values, preferably 1:0.04-0.12, wherein the aluminum source is calculated as alumina.

[0060] In the present invention, the aluminum source has a wide selection range. Preferably, the aluminum source includes but is not limited to pseudo-boehmite and aluminum sol, preferably pseudo-boehmite.

[0061] In some embodiments of the present invention, preferably, the concentration of acid in the acid solution is 0.1-5wt%, for example, 0.1wt%, 0.5wt%, 1wt%, 1.5wt%, 2wt%, 3wt%, 4wt%, 5wt%, and any value in the range consisting of any two values, preferably 0.5-2wt%.

[0062] In the present invention, the acid has a wide selection range. Preferably, the acid is selected from an inorganic acid and / or an organic acid, the inorganic acid is preferably selected from nitric acid and / or hydrochloric acid, more preferably nitric acid; the organic acid is selected from acetic acid and / or formic acid, more preferably acetic acid.

[0063] In some embodiments of the present invention, preferably, the peptization time is 1-10 h, preferably 2-6 h.

[0064] In some embodiments of the present invention, preferably, in step (2), the solid content in the slurry is 18-30wt%, for example, 18wt%, 20wt%, 22wt%, 24wt%, 26wt%, 30wt%, and any value in the range composed of any two values, preferably 18-26wt%; wherein the solid content refers to the sum of the contents of hydrogenated ZSM-5 molecular sieve, zirconium hydroxide and alumina.

[0065] In some embodiments of the present invention, preferably, the weight ratio of the composite powder to the aluminum sol is 1:2-10, for example, 1:2, 1:5, 1:6, 1:7, 1:8, 1:10, and any value in the range of any two values, preferably 1:5-8.

[0066] In the present invention, the slurry is drop-shaped into balls in an oil-ammonia column. Preferably, the oil phase in the oil-ammonia column is kerosene, wherein kerosene is preferably C 10 -C 16 alkane; the concentration of the aqueous ammonia phase is preferably 5-8wt%; the drop ball temperature is preferably 10-30°C.

[0067] In some embodiments of the present invention, preferably, the slurry is introduced into an oil-ammonia column for drop ball forming at a temperature of 10-30°C, and the wet balls are taken out from the ammonia water phase, preferably dried at 50-80°C for 8-24h to obtain dry balls.

[0068] In the present invention, the dry ball is immersed in a sulfuric acid solution, and the dry ball absorbs sulfate in the sulfuric acid solution and connects with the zirconium oxide in the composite carrier with a specific force to form an effective active component.

[0069] In some embodiments of the present invention, preferably, the concentration of sulfuric acid in the sulfuric acid solution is 0.1-10 wt %, preferably 0.2-6 wt %.

[0070] In some embodiments of the present invention, preferably, the weight ratio of the dry ball and the sulfuric acid solution is 1:0.5-1.2, preferably 1:0.5-0.8; further preferably, the immersion time of the dry ball and the sulfuric acid solution is preferably 2-6h, and the impregnated product is dried at 90-120°C for 4-20h, and then the dried product is calcined at 500-800°C for 2-8h to obtain a composite carrier, and the particle size of the composite carrier is 1.2-2.5mm, preferably 1.4-2.2mm.

[0071] In the present invention, unless otherwise specified, the solution containing soluble rare earth compounds and / or soluble Group VA element compounds means that the solution may contain soluble rare earth compounds or soluble Group VA compounds, or may contain soluble rare earth compounds and soluble Group VA compounds at the same time.

[0072] In some embodiments of the present invention, preferably, in step (3), the weight ratio of the composite carrier to the solution containing the soluble rare earth compound and / or the soluble Group VA element compound is 1:0.5-1.2, for example, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.2, and any value in the range consisting of any two values, preferably 1:0.5-1.

[0073] In the present invention, in step (3), the composite carrier and the solution containing the soluble rare earth compound and the soluble Group VA element compound are preferably impregnated at 10-40°C for 1-4h, preferably 2-3h, and the impregnated product is preferably dried at 90-120°C for 4-20h, and the dried product is preferably calcined at 500-600°C for 2-8h, preferably 4-6h, to obtain a catalyst.

[0074] In some embodiments of the present invention, preferably, in the solution containing the soluble rare earth compound and / or the soluble Group VA element compound, the concentration of the soluble rare earth compound is 0.1-10wt%, preferably 0.1-6wt%; the concentration of the soluble Group VA element compound is 1-10wt%, preferably 1-8wt%. Here, and / or means that the solution may contain the soluble rare earth compound or the soluble Group VA element compound, or may contain both the soluble rare earth compound and the soluble Group VA element compound.

[0075] In some embodiments of the present invention, preferably, the soluble rare earth compound is selected from nitrates and / or chlorates of rare earth elements, for example, lanthanum nitrate, lanthanum chlorate, cerium nitrate, cerium chlorate, but the present invention is not limited thereto.

[0076] In some embodiments of the present invention, preferably, the soluble Group VA element compound includes but is not limited to at least one of phosphoric acid, antimony nitrate and antimony acetate.

[0077] In the present invention, in order to further improve the pore distribution of the hydrogen-type ZSM-5 zeolite in the catalyst, more mesoporous channels are introduced while the original pore structure of the hydrogen-type ZSM-5 zeolite remains unchanged, so that the catalyst provides more accessible acid sites. Preferably, the method further comprises: modifying the hydrogen-type ZSM-5 zeolite.

[0078] In some embodiments of the present invention, preferably, the modification process comprises:

[0079] (a) treating the hydrogen ZSM-5 zeolite and sodium carbonate solution with a weak base, filtering, and drying to obtain a modified zeolite;

[0080] (b) exchanging ammonium ions with the modified zeolite and the ammonium salt solution, filtering, drying and calcining to obtain a hierarchical pore hydrogen-type ZSM-5 zeolite.

[0081] In the present invention, in step (a), the hydrogen-type ZSM-5 zeolite is weakly treated with sodium carbonate solution so that the treated zeolite has multi-level pores, and then washed with water and preferably dried at 90-120° C. for 2-8 hours to obtain a modified zeolite.

[0082] In some embodiments of the present invention, preferably, the conditions for the weak base treatment and the ammonium ion exchange each independently include: a temperature of 50-100°C, preferably 60-90°C; a time of 1-10h, preferably 4-6h; a rotation speed of 200-800rpm, preferably 300-600rpm.

[0083] In some embodiments of the present invention, preferably, in step (a), the weight ratio of the hydrogen ZSM-5 zeolite to the sodium carbonate solution is 1:0.1-10, for example, 1:0.1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, and any value in the range consisting of any two values, preferably 1:2-5.

[0084] In some embodiments of the present invention, further preferably, the concentration of sodium carbonate in the sodium carbonate solution is 0.05-20wt%, preferably 0.1-10wt%.

[0085] In the present invention, in step (b), the modified zeolite is subjected to amine ion exchange, and then dried and calcined to be converted into a hierarchical pore hydrogen-type ZSM-5 zeolite, wherein the drying temperature is preferably 90-120°C, and the time is preferably 2-8h; the calcination temperature is preferably 500-600°C, and the time is preferably 2-10h.

[0086] In the present invention, in order to completely remove the Na ions in the ZSM-5 zeolite, preferably, the number of ammonium ion exchanges is not less than 1, preferably 2-3 times.

[0087] In some embodiments of the present invention, preferably, the weight ratio of the modified zeolite to the ammonium salt solution is 1:3-20, for example, 1:3, 1:5, 1:8, 1:10, 1:12, 1:15, 1:20, and any value in the range consisting of any two values, preferably 1:5-15.

[0088] In some embodiments of the present invention, further preferably, the concentration of the ammonium salt in the ammonium salt solution is 0.05-10 wt %, preferably 0.05-5 wt %.

[0089] In the present invention, the type of the ammonium salt has a wide selection range, as long as the ammonium salt can be hydrolyzed into ammonium ions. Preferably, the ammonium salt is selected from ammonium chloride and / or ammonium nitrate.

[0090] In some embodiments of the present invention, preferably, the total specific surface area of ​​the multi-level pore hydrogen-type ZSM-5 zeolite is 300-480 m 2 / g, preferably 350-440m 2 / g; mesopore specific surface area 36-200m 2 / g, preferably 40-100m 2 / g.

[0091] The third aspect of the present invention provides a method for regenerating a catalyst for processing light hydrocarbons, the method comprising: regenerating a deactivated catalyst and an oxygen-containing gas in the presence of an inert gas to obtain a regenerated catalyst; wherein the deactivated catalyst is a catalyst that reacts continuously for 120 hours, and the catalyst is the catalyst provided in the first aspect, or a catalyst obtained by the method provided in the second aspect.

[0092] In the present invention, the regeneration conditions have a wide range of selection. Preferably, the regeneration conditions include: temperature of 450-550°C, preferably 460-520°C; pressure of 0.1-3MPa, preferably 0.5-2MPa; time of 5-40h, preferably 8-20h.

[0093] In some embodiments of the present invention, preferably, the volume ratio of the oxygen-containing gas to the deactivated catalyst is 250-1000:1, preferably 500-1000:1.

[0094] In some embodiments of the present invention, preferably, the oxygen-containing gas is a mixed gas of oxygen and an inert gas, and the oxygen content in the oxygen-containing gas is 0.5-5% by volume, preferably 0.5-2% by volume. In the present invention, unless otherwise specified, the inert gas includes but is not limited to nitrogen, helium, argon, neon, preferably nitrogen.

[0095] The fourth aspect of the present invention provides a method for processing light hydrocarbons, which comprises: contacting and reacting light hydrocarbons and a catalyst in the presence of a non-hydrogen gas; the catalyst is the catalyst provided in the first aspect, or a catalyst prepared by the method provided in the second aspect.

[0096] The catalyst provided by the present invention is used to process light hydrocarbons (especially light naphtha) to convert them into aromatic hydrocarbons and low-carbon olefins under non-hydrogenation conditions, that is, the light naphtha undergoes a series of reactions such as cracking, hydrogen transfer, aromatization, etc. under the action of the catalyst to generate liquid products containing aromatic hydrocarbons, and at the same time, a propylene-rich liquefied gas component and an ethylene-rich dry gas component are produced as by-products.

[0097] By adopting the method for processing light hydrocarbons provided by the present invention, light hydrocarbons (especially light naphtha) do not need to be pre-refined; at the same time, the reaction can adopt a moving bed reactor or a fixed bed reactor, and a moving bed reactor is preferably adopted to better ensure a smooth and continuous reaction; in order to avoid frequent switching of reactors due to catalyst regeneration, it is preferred to adopt a moving bed device with multiple reactors for the reaction.

[0098] In some embodiments of the present invention, preferably, the reaction conditions include: temperature of 400-650°C, preferably 450-600°C, more preferably 520-600°C; pressure of 0.01-2MPa, preferably 0.02-1MPa, more preferably 0.02-0.3MPa; mass space velocity of 0.01-10h -1 , preferably 0.05-5h -1 , preferably 0.1-2h -1 .

[0099] In some embodiments of the present invention, preferably, the volume ratio of the non-hydrogen gas to the light hydrocarbon is 200-1000: 1, preferably 400-1000: 1, more preferably 500-800: 1. Further preferably, the non-hydrogen gas includes but is not limited to N2 and CO.

[0100] In the present invention, the types of light hydrocarbons are as defined above, and the present invention will not elaborate on them here.

[0101] The present invention will be described in detail below through examples.

[0102] The specific surface area parameters and mesopore volume parameters were measured using the ASTM D4365 method; the instrument used was Micromeritics' AsAp2400 static nitrogen adsorption instrument; the test process was as follows: the catalyst sample was degassed at 300 °C for 4 h to a vacuum degree of 1.33 × 10 -2 Pa, and then nitrogen is contacted with the adsorbent to be tested at liquid nitrogen temperature (-196°C) to reach static adsorption equilibrium, and the amount of nitrogen adsorbed by the adsorbent is calculated from the difference between the nitrogen intake and the amount remaining in the gas phase after adsorption. Then, the two-parameter BET formula is used to calculate the specific surface area and pore volume, and the BJH formula is used to calculate the pore size distribution and the corresponding mesopore volume.

[0103] The particle size parameters were measured using ASTM D4513-11;

[0104] The most probable pore diameter parameter is measured using ASTM D4641-17.

[0105] The compositions of the composite supports and catalysts prepared in Examples 1-12 and Comparative Examples 1-3 are listed in Table 1, and the physical properties of the composite supports and catalysts are listed in Table 2.

[0106] Example 1

[0107] (1) Preparation of hierarchical pore hydrogen-type ZSM-5 zeolite

[0108] (a) Weak alkali treatment: 100 g of hydrogen-type ZSM-5 zeolite (SiO2 / Al2O3 molar ratio of 150, total specific surface area of ​​350 m 2 / g, mesopore specific surface area is 25m 2 / g) and 1000g of 2wt% Na2CO3 aqueous solution for weak alkali treatment, the conditions of the weak alkali treatment include: temperature 90°C, time 4h, rotation speed 500rpm, filtering, washing the obtained solid with deionized water until the washing liquid is neutral, and drying at 110°C for 5h to obtain a modified zeolite;

[0109] (b) Ammonium ion exchange: 100 g of the modified zeolite was subjected to ammonium ion exchange twice with 1000 g of 5 wt % NH4Cl aqueous solution, and the solid obtained after ion exchange was dried at 110° C. for 5 h and calcined at 550° C. for 5 h to obtain a hierarchical hydrogen-type ZSM-5 zeolite (SiO2 / Al2O3 molar ratio of 150, total specific surface area of ​​400 m 2 / g, mesopore specific surface area is 45m 2 / g).

[0110] (2) Preparation of composite powder

[0111] 52 g of zirconium oxychloride (ZrOCl2·8H2O, analytical grade) was dissolved in 500 g of deionized water to form a clear aqueous solution, to which 40 g of the above-mentioned multi-level pore hydrogen-type ZSM-5 zeolite (SiO2 / Al2O3 molar ratio of 150) was added under stirring. After stirring evenly, 6 wt% ammonia water was added dropwise until the pH value was 8, and the mixture was filtered. The obtained solid was washed with water and dried at 110°C for 4 h to obtain a composite powder.

[0112] (3) Preparation of composite carrier

[0113] Take 32g of pseudo-boehmite ( SB powder, alumina content of 75wt%), under stirring, add 190g of 1.1wt% nitric acid aqueous solution, after 2h peptization, to obtain an aluminum sol with an alumina content of 11wt%; add 36g of the above composite powder, stir at a high speed of 120rpm for 3h to obtain a slurry containing zeolite and zirconium hydroxide, the solid content of the slurry is 24wt%;

[0114] The slurry was dropped into an oil-ammonia column to form a ball, the dropping temperature was 15°C, the oil phase in the oil-ammonia column was kerosene, the thickness was 10 cm, the thickness of the ammonia water phase was 200 cm, and the ammonia water concentration was 6 wt%; the wet ball was taken out from the bottom of the ammonia water layer, dried at 60°C for 10 h, and the obtained dry ball was impregnated with a sulfuric acid solution with a concentration of 4.9 wt% for 4 h (liquid / solid weight ratio was 1:1), then dried at 110°C for 4 h, and calcined at 700°C for 3 h to obtain a composite carrier A1;

[0115] Among them, the TEM image of the composite carrier A1 is as follows Figure 1 As shown by Figure 1 It can be seen that compared with ZSM-5 zeolite, the zirconium oxide in the composite carrier forms a rich mesoporous structure on the surface of the hydrogen-type ZSM-5 zeolite, which accelerates the diffusion of reactants and products, further inhibits bimolecular reactions such as hydrogen transfer that consume light olefins, improves the selectivity of light olefins, and significantly improves the reaction effect.

[0116] (4) Preparation of Catalyst

[0117] 30 g of composite carrier A1 was impregnated with 30 g of a solution containing 3 wt% lanthanum chloride and 6 wt% phosphoric acid at 25°C for 2 h. The impregnated solid was dried at 110°C for 4 h and calcined at 550°C for 4 h to obtain catalyst S1.

[0118] Among them, the pore distribution curve of catalyst S1 is as follows Figure 2 As shown by Figure 2 It can be seen that after multi-level pore treatment, catalyst S1 has an obvious mesoporous structure.

[0119] Example 2

[0120] The method of Example 1 is followed, except that in step (2), 52 g of zirconium oxychloride (ZrOCl2·8H2O, analytically pure) is replaced by 26 g of zirconium oxychloride (ZrOCl2·8H2O, analytically pure); 40 g of the above-mentioned multi-level pore hydrogen-type ZSM-5 zeolite (SiO2 / Al2O3 molar ratio is 150) is replaced by 50 g of the above-mentioned multi-level pore hydrogen-type ZSM-5 zeolite (SiO2 / Al2O3 molar ratio is 150) to obtain a composite powder; the other conditions are the same to obtain a composite carrier A2 and a catalyst S2.

[0121] Among them, the pore distribution curve of catalyst S2 is as follows Figure 2 As shown by Figure 2 It can be seen that compared with catalyst S1, the mesopore specific surface area and pore volume of catalyst S2 also increase due to the increase in the content of hierarchical pore hydrogen-type ZSM-5 zeolite.

[0122] Example 3

[0123] The method of Example 1 is followed, except that in step (2), 52 g of zirconium oxychloride (ZrOCl2·8H2O, analytical grade) dissolved in 500 g of deionized water is replaced by 105 g of zirconium oxychloride (ZrOCl2·8H2O, analytical grade) dissolved in 300 g of deionized water, and 40 g of the above-mentioned multi-level pore hydrogen-type ZSM-5 zeolite (SiO2 / Al2O3 molar ratio of 150, total specific surface area of ​​400 m 2 / g, mesopore specific surface area is 45m 2 / g) was replaced with 20g of the above-mentioned hierarchical pore hydrogen-type ZSM-5 zeolite (SiO2 / Al2O3 molar ratio of 150, total specific surface area of ​​400m 2 / g, mesopore specific surface area is 45m 2 / g) to obtain a composite powder, and the other conditions were the same to obtain a composite carrier A3 and a catalyst S3.

[0124] Among them, the pore distribution curve of catalyst S3 is as follows Figure 2 As shown by Figure 2 It can be seen that compared with catalyst S1, the mesopore specific surface area and pore volume of catalyst S3 are reduced due to the reduction of the content of hierarchical pore hydrogen-type ZSM-5 zeolite.

[0125] Example 4

[0126] The method of Example 1 is followed, except that in step (3), 36 g of the above-mentioned composite powder is replaced by 24 g of the above-mentioned composite powder to obtain composite carrier A4, and the other conditions are the same to obtain catalyst S4.

[0127] Among them, the pore distribution curve of catalyst S4 is as follows Figure 2 As shown by Figure 2 It can be seen that compared with catalyst S1, catalyst S4 has a lower content of composite powder, which reduces the proportion of hierarchical pore hydrogen-type ZSM-5 zeolite in catalyst S4, and reduces the mesopore specific surface area and pore volume.

[0128] Example 5

[0129] Catalyst S5 was obtained by following the method of Example 1, except that in step (4), 30 g of a solution containing 3 wt% lanthanum chloride and 6 wt% phosphoric acid was replaced by 30 g of a solution containing 1.5 wt% lanthanum chloride and 6 wt% phosphoric acid, while other conditions were the same.

[0130] Example 6

[0131] Catalyst S6 is obtained by following the method of Example 1, except that in step (4), 30 g of a solution containing 3 wt% lanthanum chloride and 6 wt% phosphoric acid is replaced by 30 g of a solution containing 3 wt% cerium chloride and 6 wt% phosphoric acid, while other conditions are the same.

[0132] Example 7

[0133] Catalyst S7 was obtained by following the method of Example 1, except that in step (4), 30 g of a solution containing 3 wt% lanthanum chloride and 6 wt% phosphoric acid was replaced by 30 g of a solution containing 3 wt% lanthanum chloride and 12 wt% phosphoric acid, while other conditions were the same.

[0134] Example 8

[0135] Catalyst S8 is obtained by following the method of Example 1, except that in step (4), 30 g of a solution containing 3 wt% lanthanum chloride and 6 wt% phosphoric acid is replaced by 30 g of a solution containing 3 wt% lanthanum chloride and 5 wt% antimony nitrate, while other conditions are the same.

[0136] Example 9

[0137] The method of Example 1 was followed, except that in step (1a), 100 g of hydrogen-type ZSM-5 zeolite (SiO2 / Al2O3 molar ratio of 150, total specific surface area of ​​350 m 2 / g, mesopore specific surface area is 25m 2 / g) was replaced with 100 g of hydrogen-type ZSM-5 zeolite (SiO2 / Al2O3 molar ratio of 200, total specific surface area of ​​350 m 2 / g, mesopore specific surface area is 25m 2 / g), and other conditions were the same to obtain composite carrier A9 and catalyst S9.

[0138] Among them, the pore distribution curve of catalyst S9 is as follows Figure 2 As shown by Figure 2 It can be seen that compared with catalyst S1, catalyst S9, which is prepared by using ZSM-5 zeolite with a higher silicon-aluminum ratio, has a slightly lower mesopore volume.

[0139] Example 10

[0140] The method of Example 1 is followed, except that in step (1a), 1000 g of 2 wt % Na2CO3 aqueous solution is replaced by 1000 g of 5 wt % Na2CO3 aqueous solution, and other conditions are the same to obtain a composite carrier A10 and a catalyst S10.

[0141] Among them, the pore distribution curve of catalyst S10 is as follows Figure 2 As shown by Figure 2 It can be seen that after treatment with a higher concentration of Na2CO3 aqueous solution, mesopores with larger size and wider range appeared on catalyst S10.

[0142] Embodiment 11

[0143] The method of Example 1 was followed, except that step (1) was omitted, and 40 g of hydrogen-type ZSM-5 zeolite (SiO2 / Al2O3 molar ratio of 150, total specific surface area of ​​350 m 2 / g, mesopore specific surface area is 25m 2 / g) was added into the clear solution, and other conditions were the same to obtain the composite carrier A11 and catalyst S11.

[0144] Among them, the pore distribution curve of catalyst S11 is as follows Figure 2 As shown by Figure 2 It can be seen that the catalyst S11 without modification treatment (multi-level pore treatment) has no mesoporous structure and is mainly composed of microporous channels.

[0145] Example 12

[0146] Catalyst S12 is obtained by following the method of Example 1, except that in step (4), 30 g of a solution containing 3 wt% lanthanum chloride and 6 wt% phosphoric acid is replaced by 30 g of a solution containing 3 wt% lanthanum chloride, and other conditions are the same.

[0147] Comparative Example 1

[0148] (1) Preparation of carrier

[0149] Take 67.6g pseudo-boehmite ( SB powder, alumina content of 75wt%), under stirring, add 380g of 1.1wt% nitric acid aqueous solution, after 2h peptization, to obtain aluminum sol with an alumina content of 11wt%; add 50g hydrogen ZSM-5 zeolite (SiO2 / Al2O3 molar ratio of 150, total specific surface area of ​​350m 2 / g, mesopore specific surface area is 25m 2 / g), and stirred at a high speed of 120 rpm for 3 h to obtain a slurry containing zeolite and, wherein the solid content of the slurry is 20 wt%;

[0150] The slurry was dropped into an oil-ammonia column to form a ball, the dropping temperature was 15°C, the oil phase in the oil-ammonia column was kerosene, the thickness was 10 cm, the thickness of the ammonia water phase was 200 cm, and the ammonia water concentration was 6 wt%; the wet ball was taken out from the bottom of the ammonia water layer, dried at 60°C for 10 h, and activated at 550°C for 3 h to obtain a composite carrier DA1;

[0151] (2) Preparation of Catalyst

[0152] 50 g of the composite carrier DA1 was impregnated with 50 g of a solution containing 3 wt% lanthanum chloride and 6 wt% phosphoric acid at 25°C for 2 h. The impregnated solid was dried at 110°C for 4 h and calcined at 550°C for 4 h to obtain the catalyst DS1.

[0153] Among them, the pore distribution curve of catalyst DS1 is as follows: Figure 2 As shown by Figure 2 It can be seen that the catalyst DS1 treated with multi-level pores has no mesoporous structure and is mainly composed of microporous channels.

[0154] Comparative Example 2

[0155] (1) Preparation of zirconium oxide powder

[0156] 150 g of zirconium oxychloride was dissolved in 800 g of deionized water to form a clear aqueous solution, and ammonia water was added to the solution until the pH value was 8.0. The solution was filtered and the obtained solid was washed with water and dried at 110° C. for 4 h to obtain zirconium hydroxide powder.

[0157] (2) Preparation of composite carrier

[0158] Take 67.6g pseudo-boehmite ( SB powder, aluminum oxide content of 75wt%), under stirring, add 380g of 1.1wt% nitric acid aqueous solution, after 2h of peptization, to obtain aluminum sol with an aluminum oxide content of 11% by mass; add 50g of the above zirconium hydroxide powder, stir at a high speed of 120rpm for 3h to obtain a slurry containing zirconium hydroxide, the solid content of the slurry is 20wt%;

[0159] The above slurry is dropped into an oil-ammonia column to form a ball at a dropping temperature of 15°C. The oil phase of the oil-ammonia column is kerosene with a thickness of 10 cm, the thickness of the ammonia water phase is 200 cm, and the ammonia water concentration is 6 wt%; the wet ball is taken out from the bottom of the ammonia water layer, dried at 60°C for 10 h, and the obtained dry ball is immersed in a 4.9 wt% sulfuric acid solution for 4 h (liquid / solid mass ratio is 1:1), then dried at 110°C for 4 h, and calcined at 700°C for 3 h to obtain a composite carrier DA2.

[0160] (3) Preparation of Catalyst

[0161] 50 g of the composite carrier DA2 was impregnated with 50 g of a mixed solution containing 3 wt% lanthanum chloride and 6 wt% phosphoric acid at 25°C for 2 h. The impregnated solid was dried at 110°C for 4 h and calcined at 550°C for 4 h to obtain the catalyst DS2.

[0162] Comparative Example 3

[0163] The method of Example 1 is followed, except that in step (3), the dry balls are directly dried and calcined to obtain the composite carrier DA3, and the remaining steps are the same to obtain the catalyst DS3.

[0164] Table 1

[0165]

[0166] Note: *Based on the total weight of the composite carrier; **Molar ratio of SiO2 / Al2O3 in hydrogen-type ZSM-5 zeolite.

[0167] Table 2

[0168]

[0169] It can be seen from the data in Table 2 that the catalyst provided by the present invention has a relatively obvious mesoporous structure, and the mesopore specific surface area and mesopore volume are both higher than those of the comparative example.

[0170] Test Example 1

[0171] The catalysts (S1-S12 and DS1-DS3) prepared in Examples 1-12 and Comparative Examples 1-3 were tested for catalytic performance.

[0172] Test conditions: The catalysts (S1-S12 and DS1-DS3) prepared in Examples 1-12 and Comparative Examples 1-3 were respectively loaded in a small fixed bed reactor, and light naphtha with the composition shown in Table 3 was introduced into the reactor as a raw material, contacted with the catalyst and reacted. The reaction conditions included: temperature of 590°C, pressure of 0.1 MPa, mass space velocity of 0.5 h -1 , time is 24h, the volume ratio of nitrogen to light naphtha is 800, and the reaction results are listed in Table 4.

[0173] Table 3

[0174]

[0175] Table 4

[0176]

[0177] Note: Dry gases include H2, CH4 and C2 hydrocarbons.

[0178] Table 4

[0179]

[0180] Note: Dry gases include H2, CH4 and C2 hydrocarbons.

[0181] It can be seen from the data in Table 4 that, compared with Comparative Examples 1-3, using the catalyst provided by the present invention for processing light hydrocarbons can simultaneously obtain a higher yield of aromatics and a higher yield of low-carbon olefins.

[0182] Test Example 2

[0183] The catalyst S1 prepared in Example 1 was subjected to a stability test.

[0184] Test conditions: A small fixed bed reactor was loaded with the catalyst S1 prepared in Example 1, and light naphtha with the composition shown in Table 3 was introduced into the reactor as a raw material, contacted with the catalyst S1 and reacted. The reaction conditions included: temperature of 590°C, pressure of 0.1 MPa, mass space velocity of 0.5 h -1 , time is 120h, the volume ratio of nitrogen to light naphtha is 800, and the reaction results are listed in Table 5.

[0185] Table 5

[0186] Continuous reaction time, h 24 48 72 96 120 Dry gas yield, wt% 38.4 37.5 36.5 35.2 34.5 <![CDATA[(C3 + C4) yield, wt%]]> 31.0 31.3 32.1 32.6 32.7 <![CDATA[C 5+ Yield, wt%]]> 30.6 31.2 31.4 32.2 32.8 Ethylene yield, wt% 19.3 18.8 18.7 18.3 17.9 Propylene yield, wt% 21.1 21.5 21.3 20.9 20.7 Light olefin yield, wt% 40.4 40.3 40.0 39.2 38.6 Aromatic yield, wt% 27.2 26.8 26.2 25.6 25.3

[0187] Note: Dry gases include H2, CH4 and C2 hydrocarbons.

[0188] It can be seen from the data in Table 5 that with the extension of the reaction time, the aromatics yield decreased from 27.2wt% when the continuous reaction was carried out for 24h to 25.3wt% when the continuous reaction was carried out for 120h, and the average aromatics yield was greater than 26wt%; the light olefins yield decreased from 40.4wt% when the continuous reaction was carried out for 24h to 38.6wt% when the continuous reaction was carried out for 120h, and the average light olefins yield was greater than 39wt%, that is, the catalyst provided by the present invention has good aromatization activity, aromatics and light olefins selectivity and reaction stability.

[0189] Test Example 3

[0190] The catalyst S1 prepared in Example 1 was subjected to a regeneration test.

[0191] Test conditions: A small fixed bed reactor was loaded with the catalyst S1 prepared in Example 1, and light naphtha with the composition shown in Table 3 was introduced into the reactor as a raw material, contacted with the catalyst S1 and reacted. The reaction conditions included: temperature of 590°C, pressure of 0.1 MPa, mass space velocity of 0.5 h -1 , time is 120h, the volume ratio of nitrogen to light naphtha is 800, and the catalyst S1 which has been reacted continuously for 120h is regenerated as a deactivated catalyst.

[0192] Regeneration method: The reactor bed is regenerated by introducing an oxygen-containing gas with an oxygen content of 1 volume %. The regeneration conditions include: temperature of 450°C, pressure of 0.5 MPa, mass space velocity of 0.5 h -1 , time is 10h, the volume ratio of oxygen-containing gas to deactivated catalyst is 500, regenerated catalyst is obtained, and the regenerated catalyst is reused in the reaction, the reaction time is 120h, and the reaction results are listed in Table 6.

[0193] Table 6

[0194] Catalyst regeneration times 0 1 Dry gas yield, wt% 34.5 34.2 <![CDATA[(C3 + C4) yield, wt%]]> 32.7 32.6 <![CDATA[C 5+ Yield, wt%]]> 32.8 33.2 Ethylene yield, wt% 17.9 17.6 Propylene yield, wt% 20.7 21.0 Light olefin yield, wt% 38.6 38.6 Aromatic yield, wt% 25.3 25.1

[0195] Note: Dry gases include H2, CH4 and C2 hydrocarbons.

[0196] It can be seen from the data in Table 6 that after the catalyst S1 provided in Example 1 is regenerated, the catalytic activity is very close to the activity before regeneration, indicating that the catalyst provided by the present invention has good regeneration performance.

[0197] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A catalyst for processing light hydrocarbons, characterized in that: The catalyst comprises a composite carrier, and sulfate radicals and active components loaded on the composite carrier, wherein the active components comprise rare earth elements and / or Group VA elements; Based on the total weight of the composite support, the composite support contains 10-50 wt% of hydrogen-type ZSM-5 zeolite, 5-40 wt% of zirconium oxide and 10-85 wt% of aluminum oxide; Wherein, based on the total weight of the composite carrier, the sulfate content calculated as S is 0.1-15wt%; Wherein, based on the total weight of the composite carrier, the content of rare earth elements calculated as a single substance is 0.1-5wt%; the content of Group VA elements calculated as oxides is 0.1-10wt%.

2. The catalyst according to claim 1, wherein Based on the total weight of the composite support, the composite support contains 20-50 wt % of hydrogen-type ZSM-5 zeolite, 10-40 wt % of zirconium oxide and 10-70 wt % of aluminum oxide.

3. The catalyst according to claim 2, wherein In the hydrogen-type ZSM-5 zeolite, the SiO2 / Al2O3 molar ratio is 100-300:

1.

4. The catalyst according to claim 3, wherein In the hydrogen-type ZSM-5 zeolite, the SiO2 / Al2O3 molar ratio is 120-250:

1.

5. The catalyst according to claim 2, wherein The total specific surface area of ​​the hydrogen-type ZSM-5 zeolite is 300-480 m 2 / g; mesopore specific surface area is 20-35 m 2 / g.

6. The catalyst according to claim 5, wherein The total specific surface area of ​​the hydrogen-type ZSM-5 zeolite is 350-440 m 2 / g; mesopore specific surface area is 20-30 m 2 / g.

7. The catalyst according to claim 2, wherein The crystal form of the aluminum oxide is selected from at least one of α-Al2O3, β-Al2O3 and γ-Al2O3.

8. The catalyst according to claim 7, wherein The crystal form of the aluminum oxide is γ-Al2O3.

9. The catalyst according to claim 1, wherein The sulfate content calculated as S is 1-12 wt % based on the total weight of the composite carrier.

10. The catalyst according to claim 1, wherein Based on the total weight of the composite carrier, the rare earth element content calculated as a single substance is 0.1-3wt%; the group VA element content calculated as an oxide is 1-8wt%.

11. The catalyst according to claim 10, wherein The rare earth element is selected from lanthanum and / or cerium; The Group VA element is selected from phosphorus and / or antimony; The light hydrocarbons are mixed hydrocarbons of C4-C7.

12. The catalyst according to claim 11, wherein The light hydrocarbon is light naphtha containing C4-C7.

13. The catalyst according to any one of claims 1 to 12, wherein The particle size of the composite carrier is 1.2-2.5 mm.

14. The catalyst according to claim 13, wherein The particle size of the composite carrier is 1.4-2.2 mm.

15. The catalyst according to claim 13, wherein The total specific surface area of ​​the catalyst is 280-450 m 2 / g; mesopore specific surface area is 40-200 m 2 / g; mesopore volume is 0.1-0.5 cm 3 / g; the most probable pore diameter is 26-50 nm.

16. The catalyst according to claim 15, wherein The total specific surface area of ​​the catalyst is 350-440 m 2 / g; mesopore specific surface area is 40-150 m 2 / g; mesopore volume is 0.1-0.15 cm 3 / g; the most probable pore diameter is 26-32 nm.

17. A method for preparing a catalyst for processing light hydrocarbons according to any one of claims 1 to 16, characterized in that: The method comprises the following steps: (1) A composite powder containing hydrogen-type ZSM-5 zeolite and zirconium hydroxide is prepared by a co-precipitation method; (2) mixing the composite powder and aluminum sol to obtain a slurry; dropping the slurry into an oil-ammonia column to form a ball; drying the obtained wet ball to obtain a dry ball; immersing the dry ball in a sulfuric acid solution, and then drying and calcining to obtain a sulfate-loaded composite carrier; (3) The composite support is impregnated in a solution containing a soluble rare earth compound and / or a soluble Group VA element compound, and then dried and calcined to obtain a catalyst loaded with sulfate and active components.

18. The method according to claim 17, wherein: In step (1), the composite powder is prepared by the following method: mixing the hydrogen-type ZSM-5 zeolite and a soluble zirconium compound solution, and adding ammonia water to the mixture until the pH value of the solution is 7-10, and then filtering and drying.

19. The method according to claim 18, wherein: The weight ratio of the hydrogen-type ZSM-5 zeolite to the soluble zirconium compound solution is 1:0.1-10, wherein the soluble zirconium compound solution is calculated as soluble zirconium compound.

20. The method according to claim 19, wherein: The weight ratio of the hydrogen-type ZSM-5 zeolite to the soluble zirconium compound solution is 1:0.2-5, wherein the soluble zirconium compound solution is calculated as soluble zirconium compound.

21. The method according to claim 18, wherein: In the soluble zirconium compound solution, the concentration of the soluble zirconium compound is 1-50wt%.

22. The method according to claim 21, wherein: In the soluble zirconium compound solution, the concentration of the soluble zirconium compound is 2-40wt%.

23. The method according to claim 17, wherein: In step (2), the aluminum sol has an aluminum oxide content of 8-16 wt%.

24. The method according to claim 23, wherein: The aluminum sol contains 8-12 wt % aluminum oxide.

25. The method according to claim 23, wherein: The aluminum sol is obtained by peptizing an aluminum source with an acid solution; The weight ratio of the aluminum source to the acid solution is 1:0.02-0.2, wherein the aluminum source is calculated as aluminum oxide.

26. The method according to claim 25, wherein: The weight ratio of the aluminum source to the acid solution is 1:0.04-0.12, wherein the aluminum source is calculated as aluminum oxide.

27. The method according to claim 25, wherein: The acid concentration in the acid solution is 0.1-5wt%; The peptization time is 1-10h.

28. The method according to claim 27, wherein: The acid concentration in the acid solution is 0.5-2wt%; The peptization time is 2-6h.

29. The method of claim 17, wherein: In step (2), the solid content of the slurry is 18-30wt%.

30. The method of claim 29, wherein: The solid content in the slurry is 18-26wt%.

31. The method of claim 29, wherein: The weight ratio of the composite powder to the aluminum sol is 1:2-10.

32. The method according to claim 31, wherein: The weight ratio of the composite powder to the aluminum sol is 1:5-8.

33. The method of claim 29, wherein: The concentration of sulfuric acid in the sulfuric acid solution is 0.1-10wt%.

34. The method of claim 33, wherein: The concentration of sulfuric acid in the sulfuric acid solution is 0.2-6wt%.

35. The method of claim 29, wherein: The weight ratio of the dry ball to the sulfuric acid solution is 1:0.5-1.

2.

36. The method of claim 35, wherein: The weight ratio of the dry ball to the sulfuric acid solution is 1:0.5-0.

8.

37. The method of claim 17, wherein: In step (3), the weight ratio of the composite carrier to the solution containing the soluble rare earth compound and / or the soluble Group VA element compound is 1:0.5-1.

2.

38. The method of claim 37, wherein: The weight ratio of the composite carrier to the solution containing the soluble rare earth compound and / or the soluble Group VA element compound is 1:0.5-1.

39. The method of claim 37, wherein: In the solution containing the soluble rare earth compound and / or the soluble Group VA element compound, the concentration of the soluble rare earth compound is 0.1-10wt%; the concentration of the soluble Group VA element compound is 1-10wt%.

40. The method of claim 39, wherein: In the solution containing the soluble rare earth compound and / or the soluble Group VA element compound, the concentration of the soluble rare earth compound is 0.1-6wt%; the concentration of the soluble Group VA element compound is 1-8wt%.

41. The method of claim 37, wherein: The soluble rare earth compound is selected from nitrates and / or chlorates of rare earth elements; The soluble Group VA element compound is at least one selected from phosphoric acid, antimony nitrate and antimony acetate.

42. The method according to any one of claims 17 to 41, wherein: The method further comprises: modifying the hydrogen-type ZSM-5 zeolite; Wherein, the modification process includes: (a) treating the hydrogen ZSM-5 zeolite and sodium carbonate solution with a weak base, filtering, and drying to obtain a modified zeolite; (b) exchanging the modified zeolite with the ammonium salt solution for ammonium ions, filtering, drying and calcining to obtain a hierarchical pore hydrogen-type ZSM-5 zeolite.

43. The method of claim 42, wherein: The total specific surface area of ​​the multi-level pore hydrogen-type ZSM-5 zeolite is 300-480 m 2 / g; mesopore specific surface area is 36-200 m 2 / g.

44. The method of claim 43, wherein: The total specific surface area of ​​the multi-level pore hydrogen-type ZSM-5 zeolite is 350-440 m 2 / g; mesopore specific surface area is 40-100 m 2 / g.

45. The method of claim 42, wherein: The conditions for the weak base treatment and the ammonium ion exchange are independently: temperature of 50-100° C.; time of 1-10 h; rotation speed of 200-800 rpm.

46. ​​The method of claim 45, wherein: The conditions for the weak base treatment and the ammonium ion exchange are independently: temperature of 60-90° C.; time of 4-6 hours; rotation speed of 300-600 rpm.

47. The method of claim 42, wherein: The weight ratio of the hydrogen-type ZSM-5 zeolite to the sodium carbonate solution is 1:0.1-10.

48. The method of claim 47, wherein: The weight ratio of the hydrogen-type ZSM-5 zeolite to the sodium carbonate solution is 1:5-10.

49. The method of claim 42, wherein: The weight ratio of the modified zeolite to the ammonium salt solution is 1:3-20.

50. The method of claim 49, wherein: The weight ratio of the modified zeolite to the ammonium salt solution is 1:5-15.

51. A method for regenerating a catalyst for processing light hydrocarbons, characterized in that: The method comprises: regenerating a deactivated catalyst and an oxygen-containing gas in the presence of an inert gas to obtain a regenerated catalyst; Wherein, the deactivated catalyst is a catalyst that reacts continuously for 120 hours, and the catalyst is the catalyst described in any one of claims 1-16.

52. The method of claim 51, wherein: The regeneration conditions are: temperature of 450-550° C.; pressure of 0.1-3 MPa; and time of 5-40 h.

53. The method of claim 52, wherein: The regeneration conditions are: temperature of 460-520° C.; pressure of 0.5-2 MPa; and time of 8-20 h.

54. The method of claim 52, wherein: The volume ratio of the oxygen-containing gas to the deactivated catalyst is 250-1000:

1.

55. The method of claim 54, wherein: The volume ratio of the oxygen-containing gas to the deactivated catalyst is 500-1000:

1.

56. The method of claim 52, wherein: The oxygen-containing gas is a mixed gas of oxygen and an inert gas, and the oxygen content in the oxygen-containing gas is 0.5-5% by volume.

57. The method of claim 56, wherein: The oxygen-containing gas is a mixed gas of oxygen and an inert gas, and the oxygen content in the oxygen-containing gas is 0.5-2% by volume.

58. A method for processing light hydrocarbons, characterized in that: The method comprises: contacting light hydrocarbons with a catalyst and reacting them in the presence of a non-hydrogen gas; Wherein, the catalyst is the catalyst described in any one of claims 1-16.

59. The method of claim 58, wherein: The reaction conditions are: temperature 400-650°C; pressure 0.01-2 MPa; mass space velocity 0.01-10 h -1 ; Time is 90-240 h.

60. The method of claim 59, wherein: The reaction conditions are: temperature 450-600°C; pressure 0.02-1 MPa; mass space velocity 0.05-5 h -1 ; Time is 120-180 h.

61. The method of claim 60, wherein: The reaction conditions are: temperature of 520-600°C; pressure of 0.02-0.3 MPa; mass space velocity of 0.1-2 h -1 .

62. The method of claim 59, wherein: The volume ratio of the non-hydrogen-containing gas to the light hydrocarbon is 200-1000:

1.

63. The method of claim 62, wherein: The volume ratio of the non-hydrogen-containing gas to the light hydrocarbon is 400-1000:

1.

64. The method of claim 63, wherein: The volume ratio of the non-hydrogen-containing gas to the light hydrocarbon is 500-800:

1.

65. The method of claim 59, wherein: The light hydrocarbons are mixed hydrocarbons of C4-C7.

66. The method of claim 65, wherein: The light hydrocarbon is light naphtha containing C4-C7.

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