CN101497816B - Non-hydrogenation aromatization upgrading method for naphtha - Google Patents

Abstract

A method for non-hydrogenation aromatization modification of naphtha, comprising contacting naphtha with a modification catalyst under non-hydrogenation conditions to carry out an aromatization modification reaction, and the obtained modified product is contacted with an adsorbent, Adsorb the naphthalene-based compounds therein, then use a desorbent to desorb the naphthalene-based compounds adsorbed in the adsorbent, and separate the desorbent from the naphthalene-based compounds through rectification separation, and the adsorbent includes 55 to 80% by mass of lithium and/or Sodium-modified faujasite and 20-45% by mass of binder. The method can effectively remove the heavy components in the aromatized modified liquid product, reduce its final boiling point, and simultaneously obtain naphthalene compounds with higher purity.

Description

A method for non-hydroaromatization modification of naphtha

technical field

The invention relates to a method for non-hydroaromatization modification of naphtha, in particular to a method for improving the properties of a liquid product of non-hydroaromatization modification of naphtha.

Background technique

At present, FCC gasoline accounts for about 80% of my country's finished gasoline, and the olefin content of conventional FCC gasoline is as high as 50-55%. Content ≯35% standard. Therefore, the production of clean gasoline blending components with high octane number and low olefin content has become an urgent need for refineries. At present, the method of producing high-octane clean gasoline blending components in my country is mainly catalytic reforming. Due to the shortage of raw materials, many catalytic reforming units cannot operate at full capacity.

In recent years, due to the discovery of ZSM-5 shape-selective zeolite, naphtha and/or low-carbon hydrocarbons can be converted into gasoline blending components rich in aromatics under non-hydrogen-facing conditions, while high-quality liquefied gas is produced as a by-product. This technology is called aromatization modification technology. This technology has strong raw material adaptability, low requirements on raw material impurity content, aromatics potential content and distillation range range, and the reaction system does not need to be carried out in the presence of hydrogen and can be operated at low pressure, which provides refinery naphtha and low-carbon hydrocarbons The use of it has opened up an effective way. However, the aromatized gasoline product contains more heavy fractions and has a higher dry point. Studies have found that by reducing the dry point of gasoline can reduce the pollution caused by automobile exhaust. So far, there is no report on solving the high dry point of aromatized modified products.

"Chemical Engineering Design" 2003 _, Volume 13, No. 6, Page 17-19 reported "C ₁₀ Heavy Aromatics Comprehensive Utilization Process Technology". Tetramethylbenzene enrichment liquid and residual oil, among which, the durene enrichment liquid is frozen to -20°C in the crystallizer, sent to the separation unit and dried by a centrifuge, and the naphthalene filter cake is squeezed by a press to obtain naphthalene products.

CN94105030 discloses a separation method of C10 heavy aromatics, using reforming C ₁₀ ⁺ heavy aromatics as raw material, and separating durene, naphthalene and solvent oil through rectification and crystallization, and refining the C ₁₀ ⁺ heavy aromatics The operation method of variable reflux ratio is adopted in the distillation, that is, a large reflux ratio operation is used when cutting the tetramethylbenzene-rich fraction, and a small reflux ratio operation is used when cutting other fractions, so as to increase the concentration of durene in the tetramethylbenzene-rich liquid .

CN97115776 discloses a method for gas washing oil-diesel denaphthalene removal. In this method, ethylene glycol is cooled to -5～5°C, the cooling liquid ethylene glycol is input into the tube side of the heat exchanger, and then the denaphthalene to be removed is The saturated diesel oil is pumped into the shell side of the heat exchanger for heat exchange, so that the naphthalene in the saturated diesel oil is precipitated in the form of fine particles at 5-10 ° C, and flows into the oil storage tank together with the cooled diesel oil, and then passes through the centrifuge Solid-liquid separation, 50% of the naphthalene in the diesel oil after removal of naphthalene is separated to become an unsaturated solution of dissolved naphthalene, which is returned to the gas spray tower for reuse.

CN99107030 discloses a method for adsorbing and dearomatizing hydrocarbons. The boiling point range of raw materials used is between 45-300° C., and the concentration of aromatic compounds reaches 0.1-15w%. The method comprises the following steps: the feed is subjected to an adsorption step in a plurality of series fixed adsorption beds containing zeolite adsorbent to adsorb aromatic compounds, the adsorption temperature is 30-70° C., and the desorption fluid is used to wash and discharge the trapped in the pores of the adsorbent. Paraffins, isoparaffins and naphthenes, then the adsorbed aromatics are desorbed with a thermal desorption fluid while cooling the bed so that it can be used to restart the adsorption step of the next cycle, the desorption fluid is a gas or steam.

USP5177300 discloses a method for separating naphthalene from substituted benzene hydrocarbon compounds. The naphthalene is selectively adsorbed by an adsorption process, and then the naphthalene is desorbed by a desorbent. The raw material is coal tar or petroleum fraction, the distillation range is 200-250°C, including naphthalene, single-ring aromatic hydrocarbons and alkanes, the adsorbent is LiX zeolite, and the desorbent is selected from 1,2,3-trimethylbenzene, 1,3 , 5-trimethylbenzene, toluene, p-xylene, m-xylene or benzene, the adsorption temperature is 180-250°C, the desorption temperature is 20-220°C, and the pressure is sufficient to keep the feed in the liquid phase.

USP4357276 discloses a method for separating indole from naphthalene series hydrocarbons with X or Y type zeolite. Contact with desorbent B, and then contact with desorbent A to desorb the indole therein. The raw material is coal tar fraction, the distillation range ranges from 220 to 270°C, the adsorbent is X or Y zeolite, and the exchange ions are Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, Cu, Ag, Zn, Cd , Fe, Ni, Co and La, desorbent A includes C _2-10 aliphatic ether, C _7-10 aromatic ether, C _2-10 fatty ester and C _3-10 aliphatic ketone, desorbent B for alkylbenzenes.

CN1600836A discloses a method for preparing gasoline with low olefin content by upgrading straight-run gasoline. In this method, after mixing straight-run gasoline and C4-olefin fractions, they are mixed with HZSM-5-containing The catalyst is contacted and reacted, and then the dry gas, liquefied gas and gasoline components in the product are separated, but the gasoline components obtained have a higher final boiling point and cannot meet the standard of clean gasoline.

Contents of the invention

The object of the present invention is to provide a method for non-hydroaromatization of naphtha, which can significantly reduce the final distillation point of the modified gasoline obtained after aromatization and modification, and can also obtain higher purity gasoline at the same time. Naphthalene compounds.

The method for non-hydrogenation aromatization modification of naphtha provided by the invention comprises contacting naphtha with a modification catalyst under non-hydrogenation conditions to carry out an aromatization modification reaction, and the obtained modified product is mixed with an adsorbent contact, adsorb the naphthalene-based compounds therein, and then use a desorbent to desorb the adsorbed naphthalene-based compounds in the adsorbent, and separate the desorbent from the naphthalene-based compounds through rectification separation, and the adsorbent includes 55 to 80% by mass of lithium and/or Or sodium-modified faujasite and 20-45% by mass of binder.

The method of the present invention takes naphtha or naphtha and mixed carbon four as raw materials, carries out aromatization modification, and then adsorbs the modified gasoline with the adsorbent described in the present invention to remove the carbon dioxide in the modified gasoline. High boiling point products, thereby greatly reducing the dry point of aromatized gasoline, especially after the naphtha is mixed with mixed carbon four for aromatization, it can effectively solve the problem of heavy components in the obtained modified gasoline. The problem of excessively high final boiling point caused by the excessive use of carbon four fractions can not only improve the quality of modified gasoline, but also obtain gasoline products that meet national standards, thereby reducing the pollution caused by automobile exhaust. Naphthalene series compounds used in the production of chemical products such as phthalic anhydride, synthetic resin, and plant growth hormone can be obtained.

Description of drawings

Fig. 1 is a schematic flow chart of the aromatization modification method provided by the present invention.

Fig. 2 is a schematic diagram of the desorption process of the fixed bed adsorption separator of the present invention.

Detailed ways

In the method of the present invention, the liquid product obtained after naphtha or its mixture with the C4 fraction is aromatized and modified is separated by an adsorption method from the high-boiling hydrocarbons, thereby reducing the final boiling point of the aromatized modified product , so that it reaches the national standard of gasoline products. In addition, the naphthalene-based compounds adsorbed by the adsorbent, including naphthalene and its derivatives, are mainly alkylnaphthalene. Can be reused.

The content of active components in the adsorbent should be appropriate, preferably including 60-75% by mass of lithium and/or sodium modified faujasite and 25-40% by mass of binder.

The active component of the adsorbent provided by the method of the invention is modified faujasite, and also contains a certain amount of binder. The modified metal of the faujasite is lithium and/or sodium, the faujasite is X zeolite, Y zeolite or a mixture of X and Y zeolites, when the modified faujasite in the adsorbent is a mixture of LiY and LiX , wherein the mass ratio of LiX to LiY is 50-90:10-50. The binder in the adsorbent is preferably alumina, silica, bentonite or kaolin.

The modified faujasite can be prepared by conventional ion exchange method. The preparation method of the adsorbent is as follows: the modified faujasite and the precursor of the binder are mixed according to the required ratio of each component in the adsorbent, then molded, dried, and calcined at 300-600°C.

Because naphtha aromatization products, especially naphtha and mixed carbon four aromatization products contain a certain amount of high-boiling hydrocarbons, resulting in the dry point of the aromatization liquid product, that is, the final distillation point higher. In the method of the present invention, the content of hydrocarbon components above C ₁₂ in the aromatization modified product is 2-10 mass%, preferably 2-7 mass%.

When the modified liquid phase product of the present invention passes through the adsorption bed, the naphthalene compounds in it are selectively adsorbed by the adsorbent, while components such as alkanes, cycloalkanes, olefins and single-ring aromatics are not adsorbed. The temperature at which the aromatized modified product contacts the adsorbent is 10-100° C., preferably 20-80° C., and the pressure is 0.1-1.0 MPa, preferably 0.1-0.6 MPa. The suitable feed mass space velocity during adsorption separation is 0.5 to 5.0 hours ^-1 , preferably 0.5 to 3.0 hours ^-1 .

The adsorption and separation process of the aromatized modified product described in the present invention can be intermittent or continuous. For example, the adsorbent can be installed in one or more adsorption beds, while the raw material liquid is in contact with one adsorption bed, the desorbent desorbs the adsorbent through other adsorption beds. Or, the adsorbent is installed in a moving bed, which is in continuous contact with the feed liquid containing the desorbent. The moving bed can be real or simulated, and the adsorption feed flow is in the same or reverse direction with the adsorbent. touch.

The adsorbent after adsorbing the modified product can be desorbed with a desorbent, and the liquid stream rich in naphthalene compounds after desorption is preferably recovered by rectification. The desorbent is selected from C ₆ -C ₁₀ aromatic hydrocarbons, preferably benzene or alkylbenzene with one or more C ₁ -C ₃ alkyl groups, or a mixture of the two, such as 20-50% by mass of benzene and 50 ~80% by mass of a mixture of alkylbenzenes. The alkylbenzene is preferably toluene, p-xylene, 1,2,3-trimethylbenzene or 1,3,5-trimethylbenzene.

The suitable desorption temperature is 80-200°C, preferably 40-180°C, and the pressure is 0.1-0.6MPa, preferably 0.1-0.3MPa. The suitable feed mass space velocity during desorption is 0.5 to 5.0 hours ^-1 , preferably 0.5 to 3.0 hours ^-1 .

The aromatization raw material described in the method of the present invention is naphtha, and the mixed C4 fraction can also be mixed into the naphtha as a raw material, and then the aromatization modification reaction is carried out by contacting with the modification catalyst under non-hydrogen-facing conditions . The naphtha is selected from the group consisting of atmospheric initial distillation tower top oil, reformed top oil, condensate oil, catalytic cracking gasoline, hydrocracking gasoline, catalytic cracking gasoline, pyrolysis gasoline, hydrocoking gasoline, straight run One or more of gasoline. In the mixed carbon four fraction, the content of carbon four olefins is 40-90% by mass, and the rest is C ₃ -C ₅ alkanes. The preferred C4 fraction contains 40-90% by mass of butene, and the rest is propane, butane and pentane. The ratio of blending the mixed C4 fraction into the naphtha is based on the butene content therein, and the blending ratio should make the butene content in the raw material after mixing reach 10-60% by mass. The blended carbon four cuts preferably account for 30-80% by mass of the total amount of raw materials.

The aromatization modifying catalyst described in the method of the present invention comprises 0.1-5.0% by mass of modified metal oxides and 95.0-99.9% by mass of carriers, and the modified metal oxides are zinc, antimony, mixed rare earths, bismuth , molybdenum or gallium oxide, the mixed rare earth oxide contains 20-40% by mass of lanthanum oxide, 40-60% by mass of cerium oxide, 10-18% by mass of praseodymium oxide and 2-10% by mass of oxide neodymium. The carrier is composed of 50.0-80.0% by mass of HZSM-5 and 20.0-50.0% by mass of γ-Al ₂ O ₃ , and the molar ratio of silicon oxide/alumina of the HZSM-5 is 30-200, preferably 30-100 .

The aromatization modifying catalyst described in the present invention can be formed by conventional extruding, dropping ball or rolling ball method, and then the metal active component is introduced by impregnation method. The upgrading reaction can be carried out in a fixed bed reactor or a moving bed reaction-continuous regeneration reactor, and the number of reactors can be one or more. The suitable reaction temperature for aromatization modification is 250-480°C, the pressure is 0.2-0.7 MPa, the mass space velocity is 0.1-1.0 hours ^-1 , and the modification reaction is carried out under the condition of non-hydrogenation.

The stream flowing out from the upgrading reaction system passes through the gas-liquid separator, absorption and desorption tower and stabilization tower to separate dry gas, liquefied gas and liquid phase products. After desulfurization treatment, the liquefied gas leaves the factory as a qualified liquefied gas product, and all or part of the liquid phase product enters the adsorption bed to absorb the heavy components.

Further illustrate the present invention below in conjunction with accompanying drawing.

In Figure 1, the aromatization raw material enters the heat exchanger 2 through the pipeline 1, and after exchanging heat with the reaction effluent from the pipeline 3, enters the heating furnace 5 through the pipeline 4 to be heated to the reaction temperature, and enters the reforming reaction from the top through the pipeline 6 7, the aromatization reaction product enters the heat exchanger 2 through the pipeline 3, and after exchanging heat with the raw material from the pipeline 1, enters the cooler 9 through the pipeline 8 for cooling, and then enters the high-pressure separator 11 through the pipeline 10 to be separated into gas and liquid. phase, wherein the gas phase enters the middle part of the absorption and desorption tower 15 through the pipeline 12, the compressor 13 and the pipeline 14, the liquid phase material 16 is mixed with the discharge material 17 at the bottom of the absorption and desorption tower 15, and then enters the middle part of the stabilization tower 20 through the pipeline 18, and the dry gas passes through the pipeline 19 The system is discharged from the top of the absorption and desorption tower 15, and the liquefied gas is discharged from the system from the top of the stabilization tower 20 through the pipeline 21. A part of the material at the bottom of the stabilization tower 20 enters the top of the absorption and desorption tower 15 through the pipeline 22, and the other part enters the fixed bed adsorption separation through the pipeline 23 or 24 25 or 26, the dry point qualified gasoline blending component is discharged from the system through the pipeline 27 or 28 from the bottom of the fixed bed adsorption separator 25 or 26. The fixed bed adsorbers 25 and 26 are operated in parallel, one is for adsorption while the other is for desorption.

Fig. 2 is a schematic diagram of the desorption process of the fixed bed adsorption separator of the present invention. When one of the two fixed-bed adsorption separators connected in parallel is saturated with adsorption, the desorbent enters the fixed-bed adsorption separator 25 through a pipeline 29 to desorb the naphthalene compounds adsorbed in the adsorbent. The material enters the rectification tower 31 from the bottom pipeline 30 for rectification separation, the naphthalene compound is discharged from the bottom of the rectification tower 31 through the pipeline 33, and the desorbent is discharged from the top of the rectification tower 31 through the pipeline 32 for recycling.

The following examples further illustrate the present invention, but do not limit the present invention thereby.

Example 1

Prepare the adsorbent of the present invention.

(1) Preparation of LiY molecular sieve: Take 100 grams of Y-type zeolite (produced by Zhoucun Catalyst Factory of Qilu Petrochemical Company), ion-exchange with a LiCl solution with a concentration of 0.1mol/L for 5 hours, and then wash with deionized water until there is no Cl in the washing liquid ^- , dry at 110°C for 6 hours, and bake at 500°C for 3 hours. The above ion exchange was repeated three times to obtain LiY zeolite.

(2) Prepare adsorbent: mix LiY zeolite and aluminum hydroxide powder (produced by German Condea company, brand SB) at a mass ratio of 69:31, add deionized water and 1% nitric acid accounting for about 45% of solid mass, and knead After extrusion, it was dried at 110°C for 10 hours and calcined at 500°C for 4 hours to obtain Adsorbent A, which contained 75% by mass of LiY zeolite and 25% by mass of γ-alumina.

Example 2

Prepare adsorbent B by the method for example 1, difference is that (1) step is the NaCl solution ion-exchange X type zeolite (Qilu Petrochemical Company Zhoucun Catalyst Factory production) of 0.1mol/L with concentration; (2) step prepares adsorption The mass ratio of NaX zeolite and aluminum hydroxide powder added to the agent was 60:40, and the prepared adsorbent B contained 67% by mass of NaX zeolite and 33% by mass of γ-alumina.

Example 3

The adsorbent was prepared according to the method of Example 1, except that in the step (1), the mixed solution of LiCl and NaCl with a mass ratio of lithium oxide and sodium oxide of 75:25 was used to perform ion exchange on X-type zeolite to obtain LiNaX zeolite. Get LiNaX zeolite and aluminum hydroxide powder and mix by the mass ratio of 65: 35, press the method for example 1 (2) step to knead then extrude, dry, roast, contain LiNaX zeolite 72 mass %, 28% by mass of γ-alumina.

Example 4

Prepare LiY zeolite by the method of example 1 (1) step, then use the LiCl solution ion that concentration is 0.1mol/L to carry out ion exchange to X type zeolite according to the method for preparing LiY zeolite, make LiX zeolite.

LiX zeolite, LiY zeolite and aluminum hydroxide powder are mixed according to the ratio of 55: 15: 30 by mass ratio, then press the method for example 1 (2) step to knead and extrude, dry, roast, and in the adsorbent D prepared It contains 60% by mass of LiX zeolite, 16% by mass of LiY zeolite, and 24% by mass of γ-alumina.

Example 5

Prepare the adsorbent according to the method of Example 2, the difference is that the mass ratio of NaX zeolite and aluminum hydroxide powder added to the preparation of the adsorbent is 69:31, and the obtained adsorbent E contains 75% by mass of NaX zeolite, γ-oxidized Aluminum 25% by mass.

Example 6

The adsorbent is prepared according to the method of example 3, except that the mass ratio of LiNaX zeolite and aluminum hydroxide powder added to the adsorbent is 69:31, and the obtained adsorbent F contains 75% by mass of LiNaX zeolite, γ-oxidized Aluminum 25% by mass.

Example 7

Prepare the adsorbent according to the method of Example 4, the difference is that when preparing the adsorbent, LiX zeolite, LiY zeolite and aluminum hydroxide powder are mixed in a ratio of 56:13:31 by mass ratio, and LiX is contained in the obtained adsorbent G. 61% by mass of zeolite, 14% by mass of LiY zeolite, and 25% by mass of γ-alumina.

Example 8

Preparation of modified catalysts.

(1) Prepare the carrier: get 120 grams of HZSM-5 zeolite powder (produced by Shanghai Huaheng Chemical Factory) with a silica/alumina ratio of 56, 80 grams of aluminum hydroxide powder (produced by Qilu Catalyst Factory), stir well, and add 4 ml of nitric acid with a concentration of 40% by mass and 100 ml of deionized water are fully kneaded, extruded into strips with a diameter of 2 mm, dried at 110°C for 8 hours, cut into particles with a length of 2 to 3 mm, and then roasted at 570°C for 4 hours .

(2) Introduction of active components: Take 100 grams of the above-mentioned carrier, use 100 milliliters containing 1.0 grams of mixed rare earth chloride (produced by Inner Mongolia Baotou Rare Earth Industry Company, which contains 31 mass % of lanthanum oxide, 51 mass % of cerium oxide, 14 mass % % praseodymium oxide and 4% by mass neodymium oxide) were immersed in an aqueous solution at 80°C for 2 hours, dried at 120°C for 8 hours, and baked at 550°C for 4 hours.

(3) Steam treatment: put the prepared catalyst into a tubular reactor, heat up to 580° C. in air flow under normal pressure, and then change to steam treatment at this temperature for 5 hours, with a total water intake of 400 grams, and then blow dry air to cool down.

The catalyst prepared by the above method contains 0.43% by mass of mixed rare earth oxides (X-ray fluorescence analysis), 64.33% by mass of HZSM-5, and 35.24% by mass of γ-Al ₂ O ₃ , with an α value of 30.

Example 9

The following examples carry out the aromatization modification reaction.

On 100 milliliters of fixed-bed test equipments, load 100 grams of modified catalysts prepared by Example 8, with 60 mass % straight-run gasoline and 40 mass % carbon four cuts as raw materials, at 380 ° C, 0.3 MPa, mass space velocity 0.4 hours Under the condition of ^-1 , the reforming reaction is carried out. The properties and composition of the straight-run gasoline are shown in Table 1, the composition of the C4 fraction is shown in Table 2, and the group composition and distillation range of the modified liquid product are shown in Table 3.

Example 10

According to the method of Example 9, the straight-run gasoline shown in Table 1 is used as the reaction raw material to carry out the reforming reaction, and the group composition and distillation range of the obtained reforming liquid product are shown in Table 3.

Example 11

The following examples carry out adsorption experiments.

Fill 50 grams of adsorbent B on 100 milliliters of fixed-bed test equipment, carry out adsorption test to the modification reaction liquid product of example 9, adsorption condition is: temperature 60 ℃, pressure 0.1MPa, mass space velocity 1.2 hours ^-1 , adsorption time is 120 hours. The distillation range of the adsorbent bed effluent product is shown in Table 4.

Example 12

Fill 50 grams of adsorbent C on 100 milliliters of fixed-bed test equipment, carry out adsorption test to the modified reaction liquid product of example 9, adsorption condition is: temperature 20 ℃, pressure 0.1MPa, mass space velocity 2.5 hours ^-1 , adsorption time is 120 hours. The distillation range of the adsorbent bed effluent product is shown in Table 4.

Examples 13-16

Fill 50 grams of adsorbent on 100 milliliters of fixed-bed test equipment, carry out adsorption test to example 9 modification reaction liquid product, adsorption condition is: temperature 20 ℃, pressure 0.1MPa, mass space velocity 2.0 hours ^-1 , adsorption time is 120 Hour. The distillation range of the adsorbent used in each example and the effluent product of the adsorption bed is shown in Table 5.

Example 17

Fill 50 grams of adsorbent A on 100 milliliters of fixed bed test equipment, carry out the adsorption test with the modified reaction liquid product of example 10 as raw material, the adsorption conditions are: temperature 60 ℃, pressure 0.2MPa, mass space velocity 1.5 hours ⁻¹ , The adsorption time was 120 hours. The distillation range of the adsorbent bed effluent product is shown in Table 6.

Example 18

Fill 50 grams of adsorbent D on 100 milliliters of fixed-bed test equipment, carry out adsorption test with the modification reaction liquid product of example 10 as raw material, adsorption condition is: temperature 70 ℃, pressure 0.1MPa, mass space velocity 1.8 hours ^-1 , The adsorption time was 120 hours. The distillation range of the adsorbent bed effluent product is shown in Table 6.

The data in Tables 4 to 6 show that the final boiling point of the modified liquid product after adsorption is greatly reduced, all falling below 200°C, which meets the gasoline product standard stipulated by the state.

Example 19

The following examples carry out the desorption experiment.

The adsorbent C used to adsorb the modified product of Example 9 in Example 12 was desorbed. The desorbent was benzene. The desorption conditions were: temperature 150°C, pressure 0.1 MPa, mass space velocity 2.0 hours ⁻¹ , and desorption time 48 hours. The stream after desorption was recovered by rectification method for naphthalene compound and desorbent, and the content of other substances in the naphthalene compound obtained after rectification separation was 0.78% by mass.

Example 20

The adsorbents A, E, F, and G adsorbed by the modified product of Example 9 in Examples 13 to 16 were desorbed respectively. The desorbent was benzene, and the desorption conditions were: temperature 150 ° C, pressure 0.1 MPa, mass space velocity 2.0 hours ^{- 1.} The desorption time is 48 hours. The stream after desorption recovers the naphthalene compound and the desorbent therein by rectification, and the contents of other substances in the naphthalene compound obtained after rectification separation are respectively 0.76 mass%, 0.82 mass%, 0.58 mass%, and 0.62 mass%.

Example 21

The adsorbent B adsorbed by the modified liquid product of Example 11 in Example 9 was desorbed. The desorbent was 1,3,5-trimethylbenzene, and the desorption conditions were: temperature 150° C., pressure 0.1 MPa, mass space velocity 2.0 hours ⁻¹ , The desorption time is 48 hours. The stream after desorption was recovered by rectification method for naphthalene compound and desorbent, and the content of other substances in the naphthalene compound obtained after rectification separation was 0.93% by mass.

Table 1

Table 2

table 3

Table 4

table 5

Table 6

Claims (10)

1. method that petroleum naphtha is non-hydrogen aromatization modified; Comprise petroleum naphtha contacted with modifying catalyst under conditions of non-hydrogen and carry out the aromatization modification reaction, the upgraded product of gained contacts with sorbent material, adsorbs naphthalene series compound wherein; Then with the naphthalene series compound that adsorbs in the strippant desorb sorbent material; Through rectifying separation strippant is separated with naphthalene series compound, described sorbent material comprises the faujusite of 55～80 quality % lithiums and/or sodium modification and the sticker of 20～45 quality %, and the temperature of described aromatization modification reaction is that 250～480 ℃, pressure are 0.2～0.7MPa; The temperature that described upgraded product contacts with sorbent material is 10～100 ℃; Pressure is 0.1～1.0MPa, and described desorption temperature is 80～200 ℃, and pressure is 0.1～0.6MPa.

2. according to the described method of claim 1, it is characterized in that described sorbent material comprises the faujusite of 60～75 quality % lithiums and/or sodium modification and the sticker of 25～40 quality %.

3. according to claim 1 or 2 described methods, it is characterized in that described sticker is selected from aluminum oxide, silicon oxide, wilkinite or kaolin.

4. according to the described method of claim 1, it is characterized in that C in the described upgraded product ₁₂The content of above hydrocarbon component is 2～10 quality %.

5. according to the described method of claim 1, it is characterized in that described faujusite is the mixture of X zeolite or Y zeolite or X and Y zeolite.

6. according to the described method of claim 5, the faujusite that it is characterized in that described lithium and/or sodium modification is the mixture of LiY and LiX, and wherein the mass ratio of LiX and LiY is 50～90: 10～50.

7. according to the described method of claim 1; It is characterized in that in petroleum naphtha, mixing the mixed c 4 cut; Under conditions of non-hydrogen, contact with modifying catalyst then and carry out the aromatization modification reaction, the mixed c 4 cut that mixes accounts for 30～80 quality % of raw material total amount.

8. according to the described method of claim 1; It is characterized in that described aromatization modification catalyzer comprises the modified metal-oxide of 0.1～5.0 quality % and the carrier of 95.0～99.9 quality %; Described modified metal-oxide is the oxide compound of zinc, antimony, mishmetal, bismuth, molybdenum or gallium, and carrier is by the HZSM-5 of 50.0～80.0 quality % and γ-A1 of 20.0～50.0 quality % ₂O ₃Form.

9. according to the described method of claim 1, it is characterized in that described strippant is selected from C ₆～C ₁₀Aromatic hydrocarbons.

10. according to the described method of claim 9, it is characterized in that described C ₆～C ₁₀Aromatic hydrocarbons be benzene or one or more C arranged ₁～C ₃The korenyl of alkyl.

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