Method for producing clean gasoline through aromatization reaction

Abstract

The invention discloses a method for producing clean gasoline through aromatization reaction, which comprises the following steps: S1, mixing full-fraction gasoline with hydrogen, then carrying out pre-hydrotreatment, and then distilling to obtain light fraction gasoline and heavy fraction gasoline; s2, mixing the heavy fraction gasoline with hydrogen, and carrying out hydrodesulfurization to obtain a heavy fraction gasoline product; s3, carrying out adsorption desulfurization on the light fraction gasoline, and then carrying out aromatization reaction in the presence of an aromatization catalyst to obtain a light fraction gasoline product; and S4, blending the heavy fraction gasoline product and the light fraction gasoline product to obtain a clean gasoline product. Compared with a traditional gasoline hydrotreating process, the method has the advantages that the light fraction gasoline aromatization reaction unit is added, olefin can be converted into high-octane-number products such as aromatic hydrocarbon in a selective manner, and the octane number loss can be reduced while the olefin can be greatly reduced in the hydrodesulfurization process.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of clean fuel, and particularly relates to a method for producing clean gasoline through aromatization reaction. BACKGROUND

[0002] Olefins contained in gasoline are prone to form gum in the storage and combustion processes, reduce the combustion efficiency of the engine, and cause the increase of nitrogen oxide emissions from automobile exhaust. Therefore, the Beijing VI (B) gasoline quality standard, which was implemented on December 1, 2021, requires that the volume fraction of olefins be reduced to 12 v% from 18 v% of the national VI (A) standard. However, the substantial reduction of the content of olefins, which are high-octane components, will inevitably cause the loss of the octane rating of gasoline. It is of great practical significance to develop isomerization / aromatization technology for efficiently converting olefins into high-octane components.

[0003] Most of the olefins in gasoline components come from catalytic cracking (FCC) gasoline, and the reduction of olefins is mainly achieved by reducing the olefins in FCC gasoline. At present, the gasoline hydrogenation process in domestic refineries mostly adopts the method of fractionation to cut the FCC gasoline into light gasoline with high olefins and low sulfur and heavy gasoline with low olefins and high sulfur, and to treat the two in different ways to achieve clean gasoline at low cost. Limited by the reasons such as the multiple utilization ways of the FCC light gasoline (such as being used as an etherization raw material), the complex composition, the strong volatility requiring special evaluation devices, etc., there are few reports on the aromatization process of FCC light gasoline and the aromatization / isomerization behavior thereof. In addition, among the existing catalytic cracking gasoline desulfurization technologies, the Prime-G+ selective hydrogenation desulfurization process of France is mainly used. The Prime-G+ selective hydrogenation desulfurization process adopts the process of full-range pre-hydrogenation, light and heavy gasoline fractionation, and selective hydrogenation desulfurization of heavy fraction gasoline, follows the design concept of "selective deep desulfurization while minimizing the hydrogenation saturation of olefins", further reduces the octane loss while deep desulfurization, and can be used to produce clean gasoline with a sulfur content of ≯10 μg / g. However, for catalytic cracking gasoline with a high content of olefins, the problem of reducing olefins cannot be solved.

[0004] In recent years, researchers have prepared a series of catalysts with excellent isomerization / aromatization performance through means such as optimization of HZSM-5 molecular sieve synthesis conditions, metal modification, morphology control, and surface acidity adjustment, and have systematically studied the conversion behavior of olefins in full-range FCC gasoline and heavy gasoline, successfully developed gasoline hydro-upgrading technologies such as M-PHG, GARDES, Octgain, and OCT-M, and obtained large-scale popularization and application in industry, which has contributed to the upgrading of national V and national VI gasoline quality. However, due to the narrow pore channel and strong acidity of microporous ZSM-5 molecular sieve, excessive acidity will cause severe cracking, and carbon deposition is prone to occur in the reaction process, which limits the application of the molecular sieve.

[0005] Chinese patent CN111073684A discloses a process for producing clean gasoline, which uses a fluidized reactor to carry out desulfurization and aromatization reactions with mixed catalysts of adsorption desulfurization catalyst and aromatization catalyst under hydrogenation conditions to obtain clean gasoline products; but such a method has more olefin hydrogenation saturation, greater octane loss, and higher energy consumption, which is not conducive to large-scale promotion and application.

[0006] Chinese patent CN103289739A discloses a method for FCC gasoline hydrodesulfurization-liquefied gas aromatization coupled modification, in which full-range FCC gasoline is treated by selective hydrogenation and pre-desulfurization processes in sequence, and then fractionated to obtain HCN heavy components for hydrodesulfurization treatment; the HCN heavy components after hydrodesulfurization treatment are co-fed with liquefied gas into a fixed-bed multi-stage aromatization reactor to improve the octane value of the gasoline product; this method does not pre-hydrogenate the full-range FCC gasoline, has low hydrodesulfurization selectivity, and has a complex process.

[0007] Chinese patent CN102690677A discloses a method for producing high-octane clean gasoline by combining liquefied gas alkane aromatization and olefin aromatization, in which the raw material liquefied gas enters a reactor, and the olefins in the liquefied gas undergo condensation, cyclization and aromatization reactions under the action of an olefin aromatization catalyst to generate aromatic oil, and the alkanes in the liquefied gas undergo dehydrogenation, cracking, condensation, cyclization and aromatization reactions under the action of an alkane aromatization catalyst to generate aromatic oil; this method has low alkane aromatization reactivity, and the olefins are easily saturated, the olefin aromatization selectivity is poor, and the process is complex.

[0008] Chinese patent CN111068767A discloses a catalyst for producing clean gasoline, and preparation and application thereof, which comprises ZSM-5 / ZSM-22 composite molecular sieve, binder and active metal component; under the action of the catalyst, crude gasoline from a fractionation part of a catalytic cracking device is used as a raw material to produce clean gasoline with low sulfur, low olefins and high octane value; the catalyst prepared by this method has high cost, strong cracking capacity, low liquid yield and large octane loss.

[0009] Chinese patent CN114054076A discloses a catalyst for catalytic light gasoline aromatization and a preparation method thereof, which uses a composite of alumina and hierarchical pore ZSM-5 molecular sieve as a carrier, and uses Ni2P as an active metal component; the catalyst shows good aromatization performance for catalytic light gasoline; the aromatization catalyst prepared by this method has low active metal dispersion, large octane loss, and is not conducive to large-scale industrial application. SUMMARY

[0010] The present application aims to provide a method for producing clean gasoline by aromatization reaction.

[0011] To achieve the above object, the present application provides a method for producing clean gasoline by aromatization reaction, comprising the following steps:

[0012] S1, full-range gasoline is mixed with hydrogen and then pre-hydrogenation treated, and then distilled to obtain light distillate gasoline and heavy distillate gasoline;

[0013] S2, the heavy distillate gasoline is mixed with hydrogen to perform hydrodesulfurization to obtain heavy distillate gasoline product;

[0014] S3, the light distillate gasoline is subjected to adsorption desulfurization, and then subjected to aromatization reaction under the condition of an aromatization catalyst to obtain light distillate gasoline product;

[0015] S4, the heavy distillate gasoline product and the light distillate gasoline product are blended to obtain clean gasoline product.

[0016] In the method for producing clean gasoline by aromatization reaction, the cutting ratio of the light distillate gasoline and the heavy distillate gasoline in step S1 is 25:75-60:40, preferably 35:65-50:50.

[0017] In the method for producing clean gasoline by aromatization reaction, the reaction conditions for pre-hydrogenation treatment in step S1 are that the hydrogen partial pressure is 1.5-2.5 MPa, the reaction temperature is 150-250℃, the volume space velocity is 2.0-5.0 h -1 , and the hydrogen / oil volume ratio is 5-10 v / v.

[0018] In the method for producing clean gasoline by aromatization reaction, the reaction conditions for distillation in step S1 are that the overhead temperature is 75-90℃, the pressure is 0.6-0.72 MPa, the bottom temperature is 180-205℃, and the pressure is 0.6-0.75 MPa.

[0019] In the method for producing clean gasoline by aromatization reaction, the reaction conditions for hydrodesulfurization in step S2 are that the hydrogen partial pressure is 1.0-3.0 MPa, the reaction temperature is 240-300℃, the volume space velocity is 1.0-3.0 h -1 , and the hydrogen / oil volume ratio is 250-500 v / v.

[0020] In the method for producing clean gasoline by aromatization reaction, the reaction conditions for adsorption desulfurization in step S3 are that the reaction pressure is 1.0-3.0 MPa, the reaction temperature is 200-300℃, the volume space velocity is 1.0-5.0 h -1 , the hydrogen / oil volume ratio is 150:1-450:1, and the olefin content in the light distillate gasoline is 40v%-50v%.

[0021] The method for producing clean gasoline by aromatization reaction in the application, in step S3, the aromatization reaction has a reaction pressure of 1.0-2.0 MPa, a reaction temperature of 320-380℃, a volume space velocity of 1.0-3.0 h -1 -1.5 h -1 , and a hydrogen-oil volume ratio of 50:1-200:1 v / v.

[0022] The method for producing clean gasoline by aromatization reaction in the application, in step S3, the aromatization catalyst comprises 1-3 wt% of Group VIII metal oxide, 1-5 wt% of Group IIB metal oxide, 0.2-2.5 wt% of Group IVA metal oxide, 0.1-3 wt% of lanthanide metal oxide, 45-80 wt% of meso-microporous composite material, 15-50 wt% of alumina, and the balance of binder.

[0023] The catalyst in the application comprises Group IVA metal oxide, which has special electronic structure and chemical properties, can serve as effective active center, has high catalytic activity and selectivity, and can promote the aromatization reaction.

[0024] Meanwhile, the catalyst in the application also comprises meso-microporous composite material, which combines the advantages of mesoporous material and microporous material, has large specific surface area, high pore volume, and adjustable pore size distribution, is beneficial to the adsorption and diffusion of reactant molecules, improves the contact area between the catalyst and the reactant, and thus enhances the catalytic effect of the aromatization reaction.

[0025] The catalyst in the application comprises Group IVA metal oxide and meso-microporous composite material, can improve the carbon deposition resistance and deactivation resistance of the catalyst, prolong the service life of the catalyst, reduce the replacement frequency of the catalyst, and thus reduce the production cost. When the catalyst is applied to the aromatization reaction for producing clean gasoline, the aromatization rate can be improved, the maximum conversion of olefins into high-octane aromatic hydrocarbons can be achieved, the olefin content in the clean gasoline can be reduced, and the octane loss can be reduced.

[0026] The catalyst in the application comprises Group IVA metal oxide and meso-microporous composite material, and the clean gasoline prepared by using the catalyst in the aromatization reaction has low olefin content and small octane loss.

[0027] The method for producing clean gasoline by aromatization reaction in the application, the meso-microporous composite material comprises MCFs material and H-type molecular sieve, and the H-type molecular sieve is at least one of HZSM-5, HZSM-22, HZSM-23, HL, HBETA, HSAPO-5, HSAPO-11, HSAPO-31, and HSAPO-41.

[0028] The mesoporous MCFs material has the characteristics of regular and ordered three-dimensional cage channel structure, large specific surface area, uniform surface pore size and thick pore wall, which is beneficial to the high dispersion of metal active components on the surface of the carrier, the transmission and diffusion of reactants and products in the channel, and the increase of surface active centers of the catalyst to improve the catalytic activity, and the desorption of products from the surface of the catalyst to improve the selectivity of the target product.

[0029] Meanwhile, the mesoporous-microporous composite material in the catalyst also comprises H-type molecular sieve, which has unique channel structure and acidity, so that the catalyst exhibits high catalytic activity and selectivity in the aromatization reaction.

[0030] The mesoporous-microporous composite material in the catalyst comprises MCFs material and H-type molecular sieve, and the two synergize to exert their respective advantages, the high specific surface area and large pore volume of the MCFs material can be combined with the acid sites and channel structure of the H-type molecular sieve to form a composite material with high catalytic activity and selectivity. The catalyst is applied to the aromatization reaction for producing clean gasoline, and the aromatization rate can be improved, the olefin content in the clean gasoline can be reduced, and the octane number loss is small.

[0031] The method for producing clean gasoline by the aromatization reaction disclosed in the application, the IVA group metal comprises germanium, tin and platinum, and the oxide thereof can be germanium oxide, tin oxide or platinum oxide.

[0032] The method for producing clean gasoline by the aromatization reaction disclosed in the application, the IIB group metal is zinc, and the oxide thereof is zinc oxide.

[0033] The metal oxide of the group VIII in the application is nickel oxide, and the metal oxide of the lanthanide series is lanthanum oxide or cerium oxide. The binder is a conventional binder, which is not specially limited herein, and can be pseudo-boehmite, SB powder, silicon oxide or titanium oxide.

[0034] The method for producing clean gasoline by the aromatization reaction disclosed in the application, the specific surface area of the aromatization catalyst is 350-450 m 2 / g, the pore volume is 0.4-1.2 mL / g, and the average pore size is 4.5-12.5 nm. The specific surface area is in a suitable range, the contact area of the reactants with the catalyst is suitable, the catalyst has a large number of active sites, and the speed and efficiency of the catalytic reaction can be significantly improved. The suitable pore volume of the catalyst can ensure that there is enough space for the reactant molecules to enter the channel and contact the active sites, and can prevent the channel from being too large to reduce the selectivity. The suitable average pore size of the catalyst makes the catalyst suitable for small molecule reactions, prevents large molecules from blocking the channel, improves the stability of the catalyst, and further improves the service life of the catalyst.

[0035] The preparation method of the catalyst in the present application is a conventional technical operation in the art, and the present application is not specifically limited. For example, it can be prepared by the following method:

[0036] 1) treating a mixed solution comprising a MCFs material precursor and a H-type molecular sieve precursor loaded with a Group IVA metal, including crystallization, washing, drying, and calcination, to obtain a composite molecular sieve;

[0037] 2) treating a mixed system comprising the composite molecular sieve and alumina, including extrusion, drying, and calcination, to obtain a catalyst carrier;

[0038] 3) treating a system comprising the catalyst carrier and a Group IIB metal salt solution and a Group VIII metal salt solution, including ultrasonic treatment, stirring, drying, and calcination, to obtain a catalyst precursor;

[0039] 4) impregnating the catalyst precursor with a salt solution comprising a lanthanide metal, and post-treating the impregnated system, including drying and calcination, to obtain the catalyst.

[0040] Specifically, in step 1), a H-type molecular sieve precursor can be prepared first, for example, a H-type molecular sieve precursor loaded with a Group IVA metal germanium is prepared by using tetrapropylammonium bromide as a template agent and adding germanium tetrachloride; and then a MCFs material precursor is prepared, for example, by using P123 (polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer) as a template agent. Under stirring, the H-type molecular sieve precursor loaded with the Group IVA metal germanium is added dropwise into the above-mentioned MCFs material precursor solution to form a mixed solution, which is transferred to a crystallization kettle for crystallization at 120°C for 8h, followed by washing, drying at 80°C for 12h, and calcination at 550°C for 6h to obtain a composite molecular sieve.

[0041] In step 2), the above-obtained composite molecular sieve and alumina, for example, γ-Al2O3, are mixed according to a certain mass ratio, for example, the mass ratio of the composite molecular sieve to the alumina is 1:4, and then an appropriate amount of a extrusion aid, concentrated nitric acid, and water are added to obtain a mixed system, which is then fully back-mixed in an extruder and extruded into a cylinder with a certain diameter, for example, 4.5mm, and then dried at 120°C for 3h and calcined at 550°C for 3h to obtain a catalyst carrier. The extrusion aid is a conventional extrusion aid, which is not specifically limited herein and can be at least one of sesbania gum, methyl cellulose, starch, and polyvinyl alcohol.

[0042] In Step 3), a solution of a salt containing a Group IIB metal and a Group VIII metal, for example, a nitrate solution, is added to the above-mentioned catalyst carrier, ultrasonic treatment is performed for 20 min using ultrasonic waves, stirring is performed for 5 min, and then drying is performed at 110°C for 2 h, and after calcination at 550°C for 6 h, the catalyst precursor is cooled to room temperature.

[0043] In Step 4), a solution of a salt containing a lanthanide metal, for example, a nitrate solution, is impregnated into the above-mentioned catalyst precursor, and then drying is performed at 110°C for 2 h, and after calcination at 550°C for 6 h, the above-mentioned catalyst is obtained. Subsequently, it can be broken or cut to the desired length.

[0044] The method for producing clean gasoline by aromatization reaction according to the present application has a full-range gasoline with a sulfur content of less than or equal to 1000 mg / kg and an olefin content of less than or equal to 45 v%.

[0045] The present application has the following advantages:

[0046] Compared with the conventional gasoline hydroprocessing process, the addition of the light gasoline aromatization reaction unit can selectively convert olefins into high-octane products such as aromatic hydrocarbons, and in the hydrodesulfurization process, the olefins can be greatly reduced and the octane loss can be reduced.

[0047] The present application first performs adsorption desulfurization on the cut light gasoline and then performs olefin aromatization reaction, which can cut more olefin components into light gasoline, increase the light gasoline cutting ratio, reduce the olefin and sulfur content of heavy gasoline, reduce the octane loss caused by the heavy gasoline hydrodesulfurization process, and at the same time, can reduce the reaction energy consumption.

[0048] The addition of the light gasoline adsorption desulfurization unit (the reaction product is SO2) can eliminate the reaction of H2S and olefins to generate secondary sulfides, further improve the hydrodesulfurization depth, and at the same time, eliminate the carbon deposition caused by sulfur poisoning of the aromatization catalyst, and improve the anti-carbon deposition performance of the aromatization catalyst.

[0049] The added adsorption desulfurization unit can increase the light-heavy gasoline cutting ratio, cut more macromolecular sulfides into light gasoline, thereby reducing the heavy gasoline hydrodesulfurization reaction temperature, reducing the olefin saturation reaction, and further reducing the octane loss, and avoiding the occurrence of cracking carbon deposition reaction caused by the entry of heavy hydrocarbons into the high-temperature zone.

[0050] The problems of fast catalyst deactivation, high olefin saturation rate, and large gasoline octane loss in the hydrofining process of high-sulfur and high-olefin FCC gasoline are solved, the reaction process is flexible, the gasoline desulfurization rate is high, the product octane loss is small, and the gasoline yield is increased. BRIEF DESCRIPTION OF DRAWINGS

[0051] Figure 1This is a schematic flowchart of the method for producing clean gasoline by aromatization reaction according to the present invention;

[0052] Figure 2 XRD diffraction patterns of the catalysts synthesized in Examples 1-3 of this invention;

[0053] Figure 3 TEM image of the catalyst synthesized in Example 2 of this invention;

[0054] Figure 4 The adsorption-desorption curves of the catalysts synthesized in Examples 1-3 of this invention.

[0055] In the attached figures, the following labels are used:

[0056] 1. Full-range gasoline; 2. Pre-hydrogenated product; 3. Light-range gasoline; 4. Heavy-range gasoline; 5. Light-range gasoline after adsorption desulfurization; 6. Light-range gasoline product; 7. Heavy-range gasoline product; 8. Clean gasoline product; A. Pre-hydrogenation reactor; B. Distillation unit; C. Adsorption desulfurization reactor; D. Aromatization reactor; E. Hydrodesulfurization reactor. Detailed Implementation

[0057] The present invention will now be described in detail through embodiments. It should be noted that the following embodiments are only for further illustration of the present invention and should not be construed as limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above description.

[0058] like Figure 1 As shown, firstly, full-range gasoline 1 is mixed with hydrogen and fed into pre-hydrogenation reactor A. The reaction proceeds under the influence of a pre-hydrogenation catalyst to obtain pre-hydrogenated product 2. In this reaction, light thiols from the light gasoline are transferred to the heavy gasoline via a sulfide reaction, effectively reducing the sulfur content of the light gasoline. This further increases the cut point of the light gasoline and reduces the octane number loss caused by olefin saturation due to hydrodesulfurization. The pre-hydrogenation catalyst can be a nickel-molybdenum-alumina-based catalyst. Pre-hydrogenated product 2 then enters distillation unit B, where it is further divided into... Light distillate gasoline 3 and heavy distillate gasoline 4 are produced. Light distillate gasoline 3 enters adsorption desulfurization reactor C for adsorption desulfurization. After adsorption desulfurization, light distillate gasoline 5 enters aromatization reactor D and reacts under the aromatization catalyst. Through the polymerization, cracking, aromatization and hydrogen transfer processes of olefins, the octane number of the gasoline product is restored to obtain light distillate gasoline product 6. Heavy distillate gasoline 4 is mixed with hydrogen and then enters hydrodesulfurization reactor E for desulfurization to obtain heavy distillate gasoline product 7. Light distillate gasoline product 6 and heavy distillate gasoline product 7 are blended to obtain the final clean gasoline product 8.

[0059] The present invention will be described in detail below through specific embodiments.

[0060] Example 1

[0061] I. Preparation of ZSM-5 molecular sieve precursor

[0062] 1) 35 g of deionized water, 0.9 g of sodium hydroxide and 0.5 g of sodium metaaluminate were weighed out with 3.61 g of tetrapropyl ammonium bromide as a template agent, and stirred in a water bath at 35°C until a uniform solution was formed;

[0063] 2) 4 g of tetrapropyl ammonium bromide was slowly added to the above solution, and the water bath stirring was continued;

[0064] 3) 20 g of silica sol was gradually added to the solution obtained in step 2) (the addition speed is preferably moderate), and stirring was continued until the system was uniform;

[0065] 4) 3.216 g of germanium tetrachloride was dissolved in 30 g of water and slowly added to the material system obtained in step 3), and stirring was continued until the system was uniform;

[0066] 5) The material obtained in step 4) was transferred to a crystallization kettle, and crystallization was carried out at 170°C for 72 h;

[0067] 6) After the crystallization process was completed, the crystallization kettle was removed and subjected to water cooling treatment, and a ZSM-5 molecular sieve precursor with a silicon-aluminum ratio of 54 was obtained.

[0068] II. Preparation of MCFs material precursor solution:

[0069] 1) 4 g of template agent P123 was added to 520 mL of 2 mol / L HCl solution at 35°C, and stirred and dissolved until the obtained solution was clear and transparent, which was recorded as a first mixed solution;

[0070] 2) 30 g of n-hexane was added to the first mixed solution, and stirring was continued for 1 h;

[0071] 3) 35.9 g of ethyl silicate (TEOS) was added dropwise under stirring, and the MCFs material precursor solution was obtained after 2 h of continuous stirring;

[0072] The H + concentration in the MCFs material precursor solution was 2.0 mol / L; and the molar ratio of the raw material amount was P123:n-hexane:TEOS:HCl:H2O=0.004:2.0:1.0:6.0:140.

[0073] III. Mixing of glue:

[0074] Under the condition of fast stirring at the rotating speed of 3r / s-10r / s, 8.0g of ZSM-5 molecular sieve precursor (ZSM-5:MCFs mass ratio of 2:1) was added dropwise into the above MCFs material precursor solution, and a sol state was formed after stirring for 24h to prepare a mixed solution.

[0075] IV. Hydrothermal crystallization:

[0076] The mixed solution was transferred into a crystallization kettle and crystallized at 120℃ for 48h; then, after washing, drying at 80℃ for 12h, and calcination at 550℃ for 6h, the ZSM-5-MCFs composite molecular sieve was obtained, which was denoted as ZMH.

[0077] V. Catalyst preparation:

[0078] After 30g of ZMH composite molecular sieve and γ-Al2O3 (ZMH:γ-Al2O3 mass ratio of 2:1), 1g of sesbania powder were uniformly mixed, 1g of concentrated nitric acid and 30g of deionized water were added dropwise; after sufficient back mixing in the extruder, it was extruded into a cylindrical shape with a diameter of 4.5mm; then, drying at 120℃ for 3h; followed by calcination at 550℃ for 3h, the ZMH carrier was obtained.

[0079] First, 7.5g of zinc nitrate was dissolved in 30g of ZMH carrier, which was ultrasonically dispersed for 20min, and after stirring for 5min, it was dried at 110℃ for 2h, and then calcined at 550℃ for 6h after cooling to room temperature; then, 0.9g of lanthanum nitrate and 2.47g of nickel nitrate were dissolved in 30g of water to impregnate the ZMH carrier loaded with zinc, which was dried at 110℃ for 2h and calcined at 550℃ for 6h. According to the process requirements, it was broken or cut to the required length, and the corresponding catalyst was denoted as CAT-A1.

[0080] Catalyst pretreatment: first, the catalyst was reduced by H2 at a temperature of 400℃ and a pressure of 1.0MPa for 10h to obtain a reduced catalyst, and then the reduced catalyst was used for aromatization reaction.

[0081] First, the full-range gasoline (olefin content of 31.32v%, aromatic content of 17.79v%, sulfur content of 115.8ppm, and RON value of 89.67) was mixed with hydrogen and entered the pre-hydrogenation reactor A, and reacted under the pre-hydrogenation catalyst (nickel-molybdenum-alumina type catalyst, 20ml). The reaction conditions were: hydrogen partial pressure 1.5, reaction temperature 250℃, volume space velocity 5.0h -1, hydrogen to oil volume ratio 5 v / v. The pre-hydrogenation reaction product enters distillation device B, the overhead temperature of distillation device B is 75°C, the pressure is 0.72 MPa, the bottom temperature is 205°C, the pressure is 0.6 MPa, and the light-heavy fraction gasoline cutting ratio is 25:75. The cut heavy fraction gasoline is mixed with hydrogen and enters hydrogen desulfurization reactor E to react under the hydrogen desulfurization catalyst, and the reaction conditions are: hydrogen partial pressure 3.0 MPa, reaction temperature 240°C, volume space velocity 3.0 h -1 , hydrogen to oil volume ratio 5 v / v. The pre-hydrogenation reaction product enters distillation device B, the overhead temperature of distillation device B is 75°C, the pressure is 0.72 MPa, the bottom temperature is 205°C, the pressure is 0.6 MPa, and the light-heavy fraction gasoline cutting ratio is 25:75. The cut heavy fraction gasoline is mixed with hydrogen and enters hydrogen desulfurization reactor E to react under the hydrogen desulfurization catalyst, and the reaction conditions are: hydrogen partial pressure 3.0 MPa, reaction temperature 240°C, volume space velocity 3.0 h -1 , hydrogen to oil volume ratio 5 v / v. The pre-hydrogenation reaction product enters distillation device B, the overhead temperature of distillation device B is 75°C, the pressure is 0.72 MPa, the bottom temperature is 205°C, the pressure is 0.6 MPa, and the light-heavy fraction gasoline cutting ratio is 25:75. The cut heavy fraction gasoline is mixed with hydrogen and enters hydrogen desulfurization reactor E to react under the hydrogen desulfurization catalyst, and the reaction conditions are: hydrogen partial pressure 3.0 MPa, reaction temperature 240°C, volume space velocity 3.0 h -1 , hydrogen to oil volume ratio 5 v / v. The pre-hydrogenation reaction product enters distillation device B, the overhead temperature of distillation device B is 75°C, the pressure is 0.72 MPa, the bottom temperature is 205°C, the pressure is 0.6 MPa, and the light-heavy fraction gasoline cutting ratio is 25:75. The cut heavy fraction gasoline is mixed with hydrogen and enters hydrogen desulfurization reactor E to react under the hydrogen desulfurization catalyst, and the reaction conditions are: hydrogen partial pressure 3.0 MPa, reaction temperature 240°C, volume space velocity 3.0 h

[0082] Example 2

[0083] Example 2 and the preparation method of the catalyst of Example 1 are basically the same, except that:

[0084] I. Preparation of ZSM-5 molecular sieve precursor

[0085] 4) 3.552 g of stannous acetate is dissolved in 30 g of water and slowly added to the material system obtained in step 3), and stirred until the system is uniform;

[0086] III. Mixing glue:

[0087] 12.0 g of ZSM-5 molecular sieve precursor (ZSM-5:MCFs mass ratio is 3:1) is added dropwise to the above MCFs material precursor solution, and a sol state is formed after stirring for 24 h to prepare a mixed solution.

[0088] V. Catalyst preparation:

[0089] First, 3.2 g of zinc nitrate is dissolved in 30 g of ZMH carrier, which is ultrasonically dispersed for 20 minutes, stirred for 5 minutes, and then dried at 110°C for 2 hours. After being calcined at 550°C for 6 hours, it is cooled to room temperature. Then, 1.8 g of lanthanum nitrate and 2.47 g of nickel nitrate are dissolved in 30 g of water to co-impregnate the ZMH carrier loaded with zinc, which is dried at 110°C for 2 hours and calcined at 550°C for 6 hours. According to the process requirements, it is broken or cut to the required length, and the corresponding catalyst is marked as CAT-A2.

[0090] Firstly, the full-range gasoline and hydrogen gas were mixed into the pre-hydrogenation reactor A, and reacted under the pre-hydrogenation catalyst (nickel-molybdenum alumina catalyst, 20 ml), the reaction conditions were as follows: hydrogen partial pressure 2.5 MPa, reaction temperature 150 ℃, volume space velocity 2.0 h -1 , hydrogen-oil volume ratio 10 v / v. The pre-hydrogenation reaction product entered the distillation device B, the overhead temperature of the distillation device B was 90 ℃, the pressure was 0.6 MPa, the bottom temperature was 180 ℃, the pressure was 0.75 MPa, and the cutting ratio of light and heavy range gasoline was 60:40. The cut heavy range gasoline and hydrogen gas were mixed into the hydrodesulfurization reactor E, and reacted under the hydrodesulfurization catalyst, the reaction conditions were as follows: hydrogen partial pressure 1.0 MPa, reaction temperature 300 ℃, volume space velocity 1.0 h -1 , hydrogen-oil volume ratio 250 v / v. The cut light range gasoline entered the adsorption desulfurization reactor C for reaction, the adsorption desulfurization catalyst was NiCuZn alumina catalyst, the amount was 20 ml, the reaction conditions were as follows: 3.0 MPa, reaction temperature 200 ℃, volume space velocity 5.0 h -1 , hydrogen-oil volume ratio 450:1, and the light range gasoline after adsorption desulfurization subsequently entered the aromatization reactor D for reaction under the aromatization catalyst, the reaction conditions were as follows: reaction pressure 2.0 MPa, reaction temperature 320 ℃, volume space velocity 1.5 h -1 , hydrogen-oil volume ratio 200:1 v / v. Finally, the light range gasoline product and the heavy range gasoline product were blended to obtain the final clean gasoline product.

[0091] Example 3

[0092] The preparation method of the catalyst in Example 3 was basically the same as that in Example 1, except that:

[0093] V. Catalyst preparation:

[0094] After 30 g of ZMH composite molecular sieve and γ-Al2O3 (the mass ratio of ZMH to γ-Al2O3 was 1:1), 1 g of sesbania powder were uniformly mixed, 1 g of concentrated nitric acid and 30 g of deionized water were added dropwise; after fully back-mixing in the extruder, it was extruded into a cylindrical shape with a diameter of 4.5 mm; then dried at 120 ℃ for 3 hours; and then calcined at 550 ℃ for 3 hours to obtain a ZMH carrier. The corresponding catalyst is denoted as CAT-A3.

[0095] Firstly, the full-range gasoline and hydrogen gas were mixed into the pre-hydrogenation reactor A, and reacted under the pre-hydrogenation catalyst (nickel-molybdenum alumina catalyst, 20 ml), the reaction conditions were as follows: hydrogen partial pressure 2.5 MPa, reaction temperature 150 ℃, volume space velocity 2.0 h -1, the hydrogen to oil volume ratio is 8 v / v. The pre-hydrogenation reaction product enters distillation device B, the overhead temperature of distillation device B is 85°C, the pressure is 0.65 MPa, the bottom temperature is 190°C, the pressure is 0.7 MPa, and the light-heavy fraction gasoline cutting ratio is 40:60. The cut heavy fraction gasoline is mixed with hydrogen and enters hydrogen desulfurization reactor E to react under the hydrogen desulfurization catalyst, and the reaction conditions are: hydrogen partial pressure 2.0 MPa, reaction temperature 270°C, volume space velocity 2.0 h -1 , the hydrogen to oil volume ratio is 8 v / v. The pre-hydrogenation reaction product enters distillation device B, the overhead temperature of distillation device B is 85°C, the pressure is 0.65 MPa, the bottom temperature is 190°C, the pressure is 0.7 MPa, and the light-heavy fraction gasoline cutting ratio is 40:60. The cut heavy fraction gasoline is mixed with hydrogen and enters hydrogen desulfurization reactor E to react under the hydrogen desulfurization catalyst, and the reaction conditions are: hydrogen partial pressure 2.0 MPa, reaction temperature 270°C, volume space velocity 2.0 h -1 , the hydrogen to oil volume ratio is 8 v / v. The pre-hydrogenation reaction product enters distillation device B, the overhead temperature of distillation device B is 85°C, the pressure is 0.65 MPa, the bottom temperature is 190°C, the pressure is 0.7 MPa, and the light-heavy fraction gasoline cutting ratio is 40:60. The cut heavy fraction gasoline is mixed with hydrogen and enters hydrogen desulfurization reactor E to react under the hydrogen desulfurization catalyst, and the reaction conditions are: hydrogen partial pressure 2.0 MPa, reaction temperature 270°C, volume space velocity 2.0 h -1 , the hydrogen to oil volume ratio is 8 v / v. The pre-hydrogenation reaction product enters distillation device B, the overhead temperature of distillation device B is 85°C, the pressure is 0.65 MPa, the bottom temperature is 190°C, the pressure is 0.7 MPa, and the light-heavy fraction gasoline cutting ratio is 40:60. The cut heavy fraction gasoline is mixed with hydrogen and enters hydrogen desulfurization reactor E to react under the hydrogen desulfurization catalyst, and the reaction conditions are: hydrogen partial pressure 2.0 MPa, reaction temperature 270°C, volume space velocity 2.0 h

[0096] Examples 4-7

[0097] The preparation method of the catalyst of Examples 4-7 is basically the same as that of Example 1, and the differences are shown in Table 1.

[0098] The method for producing clean gasoline is basically the same as that of Example 1, and the differences are shown in Table 2.

[0099] Comparative Example 1

[0100] The preparation method of the catalyst of Comparative Example 1 and Example 1 is basically the same, except that the molecular sieve obtained is ZSM-5 molecular sieve.

[0101] The method for producing clean gasoline of Comparative Example 1 and Example 1 is the same.

[0102] Comparative Example 2

[0103] The preparation method of the catalyst of Comparative Example 2 and Example 1 is basically the same, except that the carrier is only MCFs material.

[0104] The method for producing clean gasoline of Comparative Example 2 and Example 1 is the same.

[0105] Comparative Example 3

[0106] The preparation method of the catalyst of Comparative Example 3 and Example 1 is basically the same, except that the carrier obtained is γ-Al2O3 carrier.

[0107] Comparative Example 3

[0108] Comparative Example 4

[0109] Comparative Example 4 was prepared in the same way as the catalyst of Example 1, except that no Group IV A metal was added during the preparation.

[0110] Comparative Example 4

[0111] Comparative Example 5

[0112] Comparative Example 5 was prepared in the same way as the catalyst of Example 1.

[0113] Comparative Example 5

[0114] Table 1

[0115]

[0116]

[0117] Table 2

[0118]

[0119] Table 3

[0120]

[0121]

[0122] Of course, the present application can have other various embodiments, and those skilled in the art can make various corresponding changes and modifications to the present application according to the present application without departing from the spirit and essence of the present application, and these corresponding changes and modifications shall all belong to the protection scope of the claims of the present application.

Claims

1. A process for the production of clean gasoline from an aromatization reaction, characterized by, The method comprises the following steps: S1, pre-hydrogenation treatment of full-range gasoline mixed with hydrogen, followed by distillation to obtain light fraction gasoline and heavy fraction gasoline; S2, hydrogen desulfurization of the heavy fraction gasoline mixed with hydrogen to obtain heavy fraction gasoline product; S3, adsorption desulfurization of the light fraction gasoline, followed by aromatization reaction under the condition of an aromatization catalyst to obtain light fraction gasoline product; S4, blending of the heavy fraction gasoline product and light fraction gasoline product to obtain clean gasoline product.

2. The method of producing clean gasoline through aromatic reaction according to claim 1, characterized in that, In step S1, the cutting ratio of light fraction gasoline and heavy fraction gasoline is 25:75-60:40, preferably 35:65-50:

50.

3. The method of producing clean gasoline through aromatic reaction according to claim 1, characterized in that, The reaction conditions of the pre-hydroprocessing in step S1 are as follows: hydrogen partial pressure 1.5-2.5 MPa, reaction temperature 150-250 °C, volume space velocity 2.0-5.0 h-1, and hydrogen to oil volume ratio 5-10 v / v. -1 , hydrogen to oil volume ratio 5-10 v / v.

4. The method of producing clean gasoline through aromatization reaction according to claim 1, characterized in that, In step S1, the reaction conditions of distillation are as follows: the overhead temperature is 75-90℃, the pressure is 0.6-0.72 MPa, the bottom temperature is 180-205℃, and the pressure is 0.6-0.75 MPa.

5. The method of producing clean gasoline through aromatic reaction according to claim 1, wherein, The reaction conditions for hydrodesulfurization in step S2 are hydrogen partial pressure 1.0-3.0 MPa, reaction temperature 240-300°C, volume space velocity 1.0-3.0 h -1 -1, and hydrogen to oil volume ratio 250-500 v / v.

6. The method of producing clean gasoline through aromatic reaction according to claim 1, wherein, The reaction conditions for adsorptive desulfurization in step S3 are as follows: reaction pressure 1.0-3.0 MPa, reaction temperature 200-300℃, volume space velocity 1.0-5.0 h -1 , hydrogen to oil volume ratio 150:1-450:1, and olefin content in light distillate gasoline 40v%-50v%.

7. The method of producing clean gasoline through aromatic reaction according to claim 1, wherein, In step S3, the reaction pressure of the aromatization reaction is 1.0 MPa to 2.0 MPa, the reaction temperature is 320°C to 380°C, the volume space velocity is 1.0 h -1 -1.5 h -1 , and the hydrogen oil volume ratio is 50:1 to 200:1 v / v.

8. The method of producing clean gasoline through aromatic reaction according to claim 1, wherein, In step S3, the aromatization catalyst comprises 1-3 wt% of Group VIII metal oxide, 1-5 wt% of Group IIB metal oxide, 0.2-2.5 wt% of Group IVA metal oxide, 0.1-3 wt% of lanthanide metal oxide, 45-80 wt% of meso-microporous composite material, 15-50 wt% of alumina, and the balance of binder.

9. The method of producing clean gasoline through aromatic reaction according to claim 8, characterized in that, The meso-microporous composite material comprises MCFs material and H-type molecular sieve, and the H-type molecular sieve is at least one of HZSM-5, HZSM-22, HZSM-23, HL, HBETA, HSAPO-5, HSAPO-11, HSAPO-31, and HSAPO-41.

10. The method of producing clean gasoline through aromatization reaction according to claim 8, characterized in that, The Group IVA metal comprises germanium, tin, and platinum.

11. The method of producing clean gasoline through aromatic reaction according to claim 8, wherein, The Group IIB metal is zinc.

12. The method of producing clean gasoline through aromatic reaction according to claim 1, wherein, The specific surface area of the aromatization catalyst is 350-450 m 2 / g, the pore volume is 0.4-1.2 mL / g, and the average pore diameter is 4.5-12.5 nm.

13. The method of producing clean gasoline through aromatization reaction according to claim 1, wherein, The sulfur content in the full-range gasoline is less than or equal to 1000 mg / kg, and the olefin content is less than or equal to 45 v%.

Images