CN1772381A - Sulfur-tolerant industrial catalyst for gas-phase ethylation of coking benzene to ethylbenzene - Google Patents

Abstract

The present invention relates to industrial sulfur tolerant catalyst for vapor ethylation of coking benzene to prepare ethyl benzene and its preparation process. The catalyst consists of nanometer HZSM-5 zeolite molecular sieve, alpha-Al2O3, and metal or non-metal oxide as modifier. Its preparation process includes high temperature water vapor or ammonia water vapor treatment of 20-200 nm crystal grain size HZSM-5 zeolite molecular sieve catalyst; and soaking the molecular sieve catalyst to support oxide of IIB element zinc, oxide of IIIB element La, oxide of VIB element Microwave oven and/or oxide one non-metal element P for modification. It may be used in the vapor ethylation of coking benzene with sulfur content of 200-800 preparation directly without needing desulfurizing and with the catalyst regenerating period as long as 60 days and other advantages.

Description

Sulfur-tolerant industrial catalyst for gas-phase ethylation of coking benzene to ethylbenzene

technical field

The invention relates to a nanometer HZSM-5 molecular sieve catalyst with excellent sulfur resistance performance and a preparation method thereof, which is used for gas-phase alkylation of coking benzene and ethylene, ethanol or dilute ethanol to produce ethylbenzene.

Background technique

Ethylbenzene is an important petrochemical raw material, about 90% is used for the production of macromolecular monomer - styrene, and the rest is used for paint solvent and pharmaceutical industry. In the field of petrochemical industry, the alkylation of benzene and ethylene is widely used to produce ethylbenzene. Phenylethylation to Ethylbenzene The traditional Friedel-Craftes alkylation process uses aluminum trichloride catalyst, but it is gradually eliminated due to the high corrosiveness of the reaction medium and the safety and waste disposal problems brought about by it. Mobil Corporation successfully developed ZSM-5, a mesoporous molecular sieve with shape-selective catalytic performance, in the 1970s, and built the world's first gas-phase ethylbenzene production device using ZSM-5 as a catalyst in 1980. Since then, the production process of ethylbenzene has gradually changed from the Friedel-Craftes hydrocarbonation process using aluminum trichloride as a catalyst to the molecular sieve catalytic process. Molecular sieve catalytic process can be divided into gas-phase alkylation reaction represented by ZSM-5 and liquid-phase alkylation reaction represented by β molecular sieve, Y molecular sieve and MCM-22 molecular sieve according to the feed state of reactants.

The gas-phase alkylation reaction is that the reaction mixture reacts in the gas phase on the surface of the catalyst. The typical catalyst is ZSM-5 zeolite molecular sieve, and the raw materials are generally petroleum benzene and high-purity ethylene. Although the reaction is carried out at 350-450°C, the xylene content in the product is as high as 0.2wt% (the ethylbenzene containing a higher concentration of xylene is unfavorable to the dehydrogenation of ethylbenzene to produce styrene), but it can be modified by molecular sieve catalyst and liquid Phase transalkylation reaction process to reduce its content, so as to meet the styrene production process. Since high temperature is not conducive to the adsorption of pollutants in the raw material on the surface of molecular sieves, the gas-phase alkylation process can withstand higher concentrations of pollutants in the raw material. In addition, the synthesis of new molecular sieves can meet the requirements of the gas-phase alkylation of low-quality raw materials to produce ethylbenzene. For example, in the patent CN94113403.2, Wang Qingya et al. Catalytic cracking dry gas (ethylene content ~ 20%) is used as raw material to carry out gas-phase alkylation with benzene at 360-450°C, 0.2-2.0MPa, benzene-ene ratio of 8-30, and ethylene mass space velocity of 0.4-2.5h ^-1 In the reaction, when the conversion rate of ethylene is 100%, the selectivity of ethylbenzene is greater than 90%, and the total selectivity of ethylbenzene is greater than 99%. The key requirements for the catalyst in the gas phase alkylation reaction are to reduce the deactivation rate of the catalyst and prolong the service life of the catalyst. The catalyst life of the gas phase alkylation reaction is generally short, because both the reactant and the product exist on the catalyst surface in a gaseous state. Although the diffusion rate of the gas is fast, the solubility of the carbon precursor on the surface is small, and the catalyst is prone to carbon deposition and deactivation.

At present, the gas-phase alkylation catalysts of petroleum benzene are relatively mature, and micron-sized hydrogen-type ZSM-5 molecular sieves are mostly used, but when coking benzene is used as raw material, its activity drops sharply. Because coked benzene contains high content of sulfides such as thiophene, the existing benzene alkylation catalysts are difficult to meet the requirements of long-term stable operation. Therefore, it is required to provide an industrial catalyst for sulfur-resistant phenethylation.

Contents of the invention

The technical problem to be solved by the present invention is to provide a nano-hydrogen ZSM-5 molecular sieve catalyst that directly uses coked benzene as raw material (total sulfur content 200ppm-800ppm) to produce ethylbenzene through gas-phase ethylation reaction and has excellent sulfur resistance and anti-coke performance. .

The present invention adopts technical scheme as follows:

The sulfur-resistant industrial catalyst used for coking benzene gas-phase ethylation to produce ethylbenzene is composed of 9.0-95.0% (weight) nano-hydrogen ZSM-5 molecular sieve, 4.0-90.0% (weight) αAl ₂ O ₃ ·H ₂ O , 1.0-10% (weight) of alkali metal oxides, non-metal oxides or metal oxides of IIB, IIIB, VIB or VIII groups.

The molecular sieve used in the sulfur-tolerant industrial catalyst for the gas-phase ethylation of coking benzene to produce ethylbenzene is ZSM-5 molecular sieve with a silicon-aluminum molar ratio greater than 12 and a grain size of 20-200 nm.

The oxides supported by the sulfur-tolerant industrial catalysts for the production of ethylbenzene from coking benzene gas-phase ethylation are alkali metal oxides MgO, non-metal oxides P ₂ O ₅ , metal oxides of groups IIB, IIIB, VIB, and VIII, ZnO, La ₂ O ₃ , MoO ₃ , Co ₂ O ₃ and NiO.

The preparation method of the sulfur-resistant industrial catalyst for the production of ethylbenzene by gas-phase ethylation of coking benzene is to combine the nano-hydrogen ZSM-5 molecular sieve with a silicon-aluminum molar ratio greater than 12 and α·Al ₂ O ₃ ·H ₂ O at a weight ratio of 1.0 on a dry basis In the mixture composed of ~10:1, add 1.0 ~ 5.0% of the dry basis weight of scallop powder and 5 ~ 15% (V/V) nitric acid aqueous solution, knead and extrude into a strip, dry at 80 ~ 120 ° C, 450 ~ Roast at 600°C for 2 to 8 hours to prepare a sodium-type ZSM-5 strip catalyst; then, prepare a 0.2-0.8 mol/liter ammonium nitrate aqueous solution, according to the catalyst weight: the volume of the ammonium nitrate aqueous solution is equal to 1-10, and the sodium-type ZSM-5 -5 strip catalysts are immersed in it, the immersion temperature is 20-50°C, the immersion time is 1-10 hours, dried at 80-120°C, and roasted at 450-600°C for 2-8 hours to obtain a hydrogen-type ZSM-5 catalyst; re-preparation 0.2-0.8 mol/liter nitric acid aqueous solution, according to the catalyst weight: the volume of ammonium nitrate aqueous solution is equal to 1-10, immerse the hydrogen-type ZSM-5 catalyst in it for acid pore expansion, the immersion temperature is 20-50°C, and the immersion time is 15-30 hours, After drying at 80-120°C and roasting at 450-600°C for 2-8 hours, the hydrogen-type ZSM-5 catalyst precursor is obtained; then, it is treated with water vapor or ammonia water vapor at high temperature; finally, the group IIB elements are impregnated by wet method Compounds of zinc, compounds of group IIIB element lanthanum, compounds of group VIB element molybdenum, compounds of group VIII element cobalt or nickel, compounds of alkali metal element magnesium, and compounds of non-metal element phosphorus are modified separately or in combination, after drying and procedures The modified composite sulfur-resistant industrial catalyst was obtained by calcining at elevated temperature.

In the preparation method of the sulfur-resistant industrial catalyst for the production of ethylbenzene by gas-phase ethylation of coking benzene, the steam treatment conditions are atmospheric pressure, temperature 300-600°C, and steam treatment with a weight space velocity of 0.2-5h ^-1 for 1-20 hours ; When treated with ammonia water vapor, the concentration of ammonia water is 0.1-1.0 mol/liter, and the pressure, temperature, and time are the same as those for water vapor treatment.

In the preparation method of the sulfur-resistant industrial catalyst for the production of ethylbenzene by gas-phase ethylation of coking benzene, the wet impregnation modification is to prepare zinc nitrate, lanthanum nitrate, cobalt nitrate, nickel nitrate, ammonium molybdate, magnesium acetate or ammonium phosphate into 0.001~ 2.0 mol/liter aqueous solution, according to catalyst weight: aqueous solution volume ratio of 1-10, soaked at 20-50 ° C for 1-10 hours, loaded on the hydrogen-type ZSM-5 catalyst treated with steam, and then heated at 80-120 ℃ drying, at a heating rate of 2-7 °C/min, from room temperature to 400-470 °C, heat preservation for 1-3 hours, and then at a heating rate of 1-3 °C/min to 470-520 °C, heat preservation for 1 ~3 hours, and finally raised to 520-550°C at a heating rate of 1-3°C/min, held for 2-6 hours, and then lowered to room temperature to obtain a modified composite sulfur-resistant industrial catalyst.

The gas-phase ethylation of coked benzene to produce ethylbenzene is carried out in a stainless steel fixed-bed tubular reactor, and a cylindrical strip-shaped catalyst (od1.5mm) with an aspect ratio of about 1 is placed in the constant temperature section of the tubular reactor. Before the reaction, the temperature of the catalyst bed was raised to 500° C. for 1 hour, and then the temperature was lowered to the reaction temperature before feeding. The reaction conditions were rapid deactivation of the catalyst and simulated industrial conditions. The modified composite nano-hydrogen ZSM-5 can be used for the direct gas-phase ethylation of coked benzene with a sulfur content of 200-800ppm to produce ethylbenzene without desulfurization process, and the catalyst regeneration cycle is 60 days, which can meet the long-term operation of industrial production Require.

Detailed ways

Example 1

Mix nanometer NaZSM-5 (SiO 2 /Al 2 O 3 molar ratio SiO ₂ /Al ₂ O ₃ is 30) and α-Al ₂ O ₃ ·H ₂ O at a ratio of 70:30, add 2 to 3% of scallop powder and 10wt % concentrated nitric acid aqueous solution kneaded and then extruded into rods, dried at 110°C, and then calcined at 540°C for 3 hours to make sodium ZSM-5 zeolite molecular sieve; exchanged three times with 0.4mol/L NH ₄ NO ₃ After washing with deionized water, dry at 110°C and roast at 540°C for six hours; finally soak in 0.6 mol/L nitric acid aqueous solution for 24 hours, wash with deionized water until pH≈7, dry at 110°C, and roast at 540°C for 3 hours A nano-hydrogen ZSM-5 catalyst with a diameter of 1.5 mm was obtained.

The above catalyst was treated with water vapor at 500°C for 2 hours with a weight space velocity of 0.5h ^-1 , and then impregnated with 0.06 mol/L lanthanum nitrate aqueous solution at room temperature for 4 hours. The weight ratio of lanthanum nitrate aqueous solution to catalyst was 2. After drying at 110°C, the temperature was programmed to rise: 450°C for 1 hour, 500°C for 1 hour, and 540°C for 3 hours to obtain the finished catalyst.

Take 1 gram of the above catalyst, put it in a fixed bed reactor, and react for 25 hours under the conditions of rapid deactivation, that is, normal pressure, temperature 360°C, molar ratio of coking benzene to ethylene 0.7, coking benzene weight space velocity 5.3h ^-1 The conversion rate of coking benzene decreased from 61.3% to 22.2%, the total selectivity of ethylbenzene increased from 85.2% to 98.1%, and the catalyst deactivation rate was 1.6 percentage points/hour.

Comparative Example 1

The same nano-hydrogen type ZSM-5 zeolite molecular sieve precursor as in Example 1, but without high-temperature steam treatment, and the rest are the same as in Example 1.

After the catalyst operated for 11 hours, the conversion rate of coked benzene dropped from 45.6% to 13.6%, the total selectivity of ethylbenzene rose from 78.5% to 95.0%, and the deactivation rate of the catalyst was 2.9 percentage points/hour.

Comparative Example 2

The same nanometer HZSM-5 zeolite molecular sieve precursor as in Example 1, the finished catalyst was treated with water steam for 2 hours at 500°C, and the rest were the same as in Example 1.

After 21 hours of catalyst operation, the coking benzene conversion rate dropped from 48.0% to 18.5%, the total selectivity of ethylbenzene rose to 96.8% from 86.7%, and the catalyst deactivation rate was 1.41%/hour, but the activity was uniform in the reaction time investigated. Lower than Example 1, it shows that the activity increases after loading lanthanum.

Example 2

The difference from Example 1 is that it is treated with high-temperature ammonia steam, the treatment conditions are 500°C, 0.5 mol/L ammonia steam for 2 hours, and the weight space velocity is 0.5h ^-1 , and the rest are the same as Example 1.

The conversion rate of coked benzene decreased from 57.2% to 24.0% after the catalyst was operated for 11 hours, the total selectivity of ethylbenzene increased from 85.6% to 96.0%, and the deactivation rate of the catalyst was 3.0%/hour.

Example 3

The difference from Example 1 lies in the different steam treatment temperature, the specific process: under the condition of 400°C, steam treatment for 2 hours, the weight space velocity is 0.5h ^-1 , and the rest is the same as Example 1.

The conversion rate of coked benzene dropped from 53.6% to 31.7% after the catalyst was operated for 25 hours, the total selectivity of ethylbenzene rose from 81.5% to 94.1%, and the deactivation rate of the catalyst was 0.88 percentage points/hour.

Example 4

The difference from Example 1 is that the water vapor treatment temperature is different, and the specific process is: under the condition of 450° C., the water vapor treatment is performed for 2 hours, and the rest are the same as in Example 1.

Get 1 gram of above-mentioned catalysts, put in the fixed-bed reactor, be different from embodiment 1 and carry out under the pressurized condition of alkylation reaction and the preheating furnace of temperature 400 ℃ before the reaction mixture enters the reaction furnace, promptly in 1.4 MPa, temperature 400 DEG C, petroleum benzene: absolute ethanol=10 (weight ratio), total space velocity 16.5h ^-1 under the conditions of carrying out alkylation reaction operation after 35 hours, benzene transformation rate is by 15.8% to 16.1%, ethylbenzene Total selectivity is from 97.7% to 99.0%, then in the system, add the thiophene of 400ppm (all the other conditions are constant), run again for 70 hours, benzene conversion rate is by 16.1% to 15.4%, ethylbenzene total selectivity becomes by 99.0% 99.3%, with no apparent tendency towards catalyst deactivation.

Example 5

The difference from Example 1 is that the water vapor treatment temperature of hydrogen ZSM-5 is different, the specific process: under the condition of 400°C, water vapor treatment for 2 hours, and the rest are the same as in Example 1.

Get 1 gram of above-mentioned catalysts, put in fixed-bed reactor, at 1.4MPa, temperature 400 ℃, petroleum benzene: coking benzene (total sulfur content 505.7ppm)=3: 1 (weight ratio), benzene: dehydrated alcohol=10 : 1 (weight ratio), total space velocity 16.5h ^-1 under the condition of carrying out alkylation reaction and running 87 hours, benzene conversion rate drops to 13.1% by 15.8%, total selectivity of ethylbenzene rises to 98.5% by 97.9%, liter When the reaction temperature is increased to 410°C (other reaction conditions remain unchanged), the benzene conversion rate increases, and after another 249 hours of operation, the benzene conversion rate remains at 15.9%. The total selectivity of ethylbenzene is 99.5%, and there is still no downward trend. It shows that the catalyst has good activity stability. When the deactivation state occurs, the service life of the catalyst can be extended and the utilization rate can be improved by increasing the reaction temperature.

Example 6

The difference from Example 4 is that the water vapor treatment temperature of the hydrogen type ZSM-5 is different, and the specific process is: 425 ° C water vapor treatment for 2 hours, and then soaked with 0.06 mol/liter lanthanum nitrate aqueous solution at room temperature for 4 hours, the weight ratio of lanthanum nitrate aqueous solution to catalyst Is 2, drying, roasting, reaction conditions and reaction charge are identical with embodiment 5.

The benzene conversion rate dropped from 16.18% to 12.1% in 139 hours of reaction operation, and rose to 14.3% after raising the reaction temperature to 415°C, but the benzene conversion rate dropped to 13.3% again when the operation reached 171 hours, while the selectivity in ethylbenzene remained at More than 98%.

Example 7

The same nanometer HZSM-5 zeolite molecular sieve precursor as in Example 1 was treated with water vapor for 2 hours at 400°C, and then impregnated with 0.06 mol/liter lanthanum nitrate aqueous solution at room temperature for 4 hours. The weight ratio of lanthanum nitrate aqueous solution to catalyst was 2. Drying and roasting are the same as in Example 1.

Take 1 gram of the above catalyst, put it into a fixed-bed reactor, and carry out the alkylation reaction under the conditions of 1.4MPa, temperature 400°C, petroleum benzene containing 800ppm thiophene with a space velocity of 9h ^-1 and ethylene space velocity of 0.65h ^-1 . After running for 7 hours, the benzene conversion rate rose from 12.9% to 17.3%, and after 70 hours, the benzene conversion rate was still 17.4%, replacing 800ppm with coking benzene (505.7ppm total sulfur content): petroleum benzene=3:1 (weight ratio) Petroleum benzene, with other conditions unchanged, the conversion rate of benzene began to drop to 15.1% after another 210 hours of operation, and the selectivity of benzene in the whole process was greater than 97%. The catalyst deactivation rate was 0.008%/hour.

Example 8

The difference of Example 7 lies in the modification of loaded zinc oxide, the specific process: immerse with 0.12 mol/L zinc nitrate aqueous solution at room temperature for 4 hours, the weight ratio of zinc nitrate aqueous solution to catalyst is 4, drying and roasting are the same as in Example 1.

Take 1 gram of the above catalyst, put it into a fixed-bed reactor, and carry out the alkylation reaction under the conditions of 1.4 MPa, temperature 400°C, petroleum benzene containing 800 ppm thiophene at a space velocity of 9 h ^-1 and ethylene at a space velocity of 0.65 h ^-1 . After running for 25 hours, the conversion rate of benzene is 17.0% to 18.1%, and the total selectivity of ethylbenzene is greater than 97%. However, after replacing 800 ppm of thiophene petroleum benzene with coking benzene (total sulfur content 505.7 ppm), the conversion rate of benzene dropped to 13.9% after seven hours, that is, the average rate of catalyst deactivation was 0.6 percentage points/hour.

Example 9

The difference from Example 7 is that the composite modification of lanthanum oxide and zinc oxide is supported by the co-impregnation method. The specific process: immerse 0.12 mol/liter zinc nitrate and 0.06 mol/liter lanthanum nitrate aqueous solution at room temperature for 4 hours, mix the nitrate aqueous solution and Catalyst weight ratio is 6, and drying, calcining are identical with embodiment 1.

Take 1 gram of the above-mentioned catalyst, put it into a fixed-bed reactor, and put it into ^a fixed-bed reactor. The gas-phase alkylation reaction was carried out under the condition of a speed of 0.65h ^-1 . After running for 33 hours, the conversion rate of benzene dropped from 15.0% to 10.7%, and the total selectivity of ethylbenzene was greater than 98%. Catalyst deactivation rate 0.1 percentage points/hour.

Example 10

The difference with Example 7 is that the amount of loaded lanthanum oxide is twice as large, and the specific process: immerse at room temperature for 4 hours with 0.12 mol/liter lanthanum nitrate aqueous solution, the weight ratio of lanthanum nitrate aqueous solution to catalyst is 2, drying, roasting, and reaction conditions And reaction feed is identical with embodiment 9.

After running for 130 hours, the conversion rate of benzene dropped from 16.1% to 9.0%, the total selectivity of ethylbenzene was greater than 98%, and the catalyst deactivation rate was 0.1 percentage point/hour.

Example 11

The difference from Example 7 lies in the modification of supported cobalt oxide, the specific process: 0.39 g of cobalt nitrate hexahydrate is fully dissolved in 20 ml of deionized water, and the weighed 5-cobalt catalyst is put into it. The aqueous solution was soaked at room temperature for 4 hours, the weight ratio of the cobalt nitrate aqueous solution to the catalyst was 4, and the drying, roasting, reaction conditions and reaction feed were the same as in Example 9.

The catalyst was operated for 56 hours, the conversion rate of benzene dropped from 13.8% to 9.8%, and the total selectivity of ethylbenzene was greater than 97%. Catalyst deactivation rate 0.1 percentage points/hour. The average conversion of benzene was 75% of that of the catalyst in Example 11 within 22 hours.

Example 12

The difference from Example 7 is the modification of the supported molybdenum oxide, the specific process: immersion at room temperature for 4 hours with 0.005 mol/liter ammonium molybdate aqueous solution, the ammonium molybdate aqueous solution and the catalyst weight ratio are 4, drying, roasting, reaction conditions and The reaction feed is the same as in Example 9.

The catalyst runs for 32 hours, the conversion rate of benzene drops from 11.2% to 8.4%, the total selectivity of ethylbenzene is greater than 97%, and the deactivation rate of the catalyst is 0.1 percentage point/hour. The average conversion of benzene was 71% of Example 11 within 22 hours.

Example 13

The difference from Example 7 lies in the modification of the loaded nickel oxide. The specific process: then use 0.046 mol/liter of nickel nitrate aqueous solution to impregnate at room temperature for 4 hours, the weight ratio of nickel nitrate aqueous solution to catalyst is 4, drying, roasting, reaction conditions and reaction The feed was the same as in Example 9.

The catalyst was operated for 22 hours, the conversion rate of benzene dropped from 10.2% to 8.6%, and the total selectivity of ethylbenzene was between 97% and 98%. Catalyst deactivation rate 0.1 percentage points/hour. But the toluene content in the product is twice that in Example 11. The average conversion of benzene in 22 hours was 56% of Example 9.

Example 14

Catalyst, reaction condition are all identical with embodiment 9. The difference is that coked benzene (total sulfur content 361.6ppm) is fed.

The reaction runs for 200 hours, the conversion rate of benzene drops from 16.9% to 7.4%, and the total selectivity of ethylbenzene is greater than 97%. The catalyst deactivation rate was 0.1 percent/hour.

Example 15

The catalyst used in Example 14 was deactivated and then regenerated. The regeneration conditions were as follows: calcination at 450°C for 1 hour in air, and then calcination at 540°C for 4 hours. With the regenerated catalyst as the reaction catalyst, the reaction of Example 14 was repeated.

The reaction was run for 220 hours, the benzene conversion rate dropped from 13.5% to 8.4%, and the catalyst deactivation rate was 0.02%/hour.

Example 16

The difference from Example 7 lies in the modification of loaded magnesium oxide. The specific process is: 1.3 grams of magnesium acetate is dissolved in 20 milliliters of deionized water, and after fully dissolving, 5 grams of catalyst are put into it. same.

Put 1 gram of catalyst in the constant temperature section of the fixed bed reactor, raise the temperature to 500°C for activation for 1 hour, and then lower the temperature to 400°C to feed the reaction, the system pressure is 1.4Mpa, and nitrogen is used as the carrier gas. The reaction raw material ratio is coking benzene (total sulfur content 361.6PPM): absolute ethanol = 10:1 (weight ratio), space velocity (WHSV) 9.92h ^-1 .

After the reaction was carried out for 16 hours, the conversion rate of benzene dropped from 11.0% to 9.8%, the deactivation rate of the catalyst was 0.1 percentage point/hour, and the total selectivity of ethylbenzene was greater than 96%.

Example 17

The difference from Example 7 lies in the modification of loaded phosphorus oxides. The specific process: first weigh 20 milliliters of deionized water, then add 0.16 grams of 85wt% concentrated phosphoric acid to it, stir evenly, then add 0.59 grams of 25wt% ammonia water, wait Put into 5 grams of catalysts again after the white precipitate of generation dissolves completely, impregnation, drying, roasting conditions are all identical with embodiment 7.

Put 1 gram of catalyst in the constant temperature section of the fixed bed reactor, raise the temperature to 500°C for activation for 1 hour, and then lower the temperature to 400°C to feed the reaction, the system pressure is 1.4Mpa, and nitrogen is used as the carrier gas. The reaction raw material ratio is coking benzene (total sulfur content 361.6PPM): absolute ethanol = 10:1 (weight ratio), space velocity (WHSV) 9.92h ^-1 .

After the reaction was carried out for 98 hours, the conversion rate of benzene dropped from 13.5% to 12.5%, the deactivation rate of the catalyst was 0.01%/hour, and the total selectivity of ethylbenzene was greater than 96%.

Example 18

The difference from Example 17 is that the amount of phosphorus oxide loaded is different. First weigh 20 ml of deionized water, then add 0.41 g of 85 wt% H ₃ PO ₄ into it, stir evenly, and then add 1.49 g of 25 wt% ammonia water , put into 5 grams of catalyst again after the white precipitate that generates is completely dissolved, and all the other preparation processes are the same as in Example 19. Reaction conditions, reaction raw materials are all consistent with embodiment 17.

The reaction was carried out for 52 hours, the benzene conversion rate dropped from the initial 14.2% to 9.2%, the catalyst deactivation rate was 0.1 percentage point/hour, and the total selectivity of ethylbenzene was greater than 97%.

Example 19

The catalyst precursor and catalyst modification are consistent with Example 9. The difference is that the raw materials are coking benzene with a total sulfur content of 360ppm and dilute ethanol with a total sulfur content of 37v%.

Take 1 gram of catalyst and put it in the constant temperature section of the fixed-bed reaction tube. Coked benzene and dilute ethanol enter the reactor through two pipelines with two plunger pumps respectively. The space velocities are 5.28h ^-1 and 1.75h ^-1 1.4MPa, reaction temperature 400°C.

The conversion rate of coking benzene and benzene at the beginning of the reaction was 6.8%, which rose to 12.6% after six hours, and dropped to 8.7% after 304 hours of operation. The catalyst deactivation rate is 0.01%/hour, and the total selectivity of ethylbenzene in the whole reaction process is greater than 98%.

Claims (6)

1. A sulfur-resistant industrial catalyst for coking benzene vapor-phase ethylation to produce ethylbenzene is characterized in that the catalyst is made of 9.0～95.0% (weight) nanometer hydrogen type ZSM-5 molecular sieve, 4.0～90.0% (weight) ) of αAl ₂ O ₃ ·H ₂ O, 1.0-10% (weight) of alkali metal oxides, non-metal oxides or metal oxides of groups IIB, IIIB, VIB, and VIII. 2. The sulfur-resistant industrial catalyst according to claim 1, characterized in that the molecular sieve used is a ZSM-5 molecular sieve with a silicon-aluminum molar ratio greater than 12 and a grain size of 20-200 nm. 3. according to the described sulfur-resistant industrial catalyst of claim 1, it is characterized in that alkali metal oxide is MgO, metalloid oxide is P ₂ O ₅ The metal oxide of IIB, IIIB, VIB, VIII group is ZnO, La ₂ O ₃ , MoO ₃ , Co ₂ O ₃ and NiO. 4. according to the preparation method of the described sulfur-resistant industrial catalyst of claim 1, it is characterized in that the method is that the nano-hydrogen type ZSM-5 molecular sieve and αAl ₂ O ₃ ·H ₂ O with a silicon-aluminum mol ratio greater than 12 by dry weight Add 1.0 to 5.0% of the dry basis weight of scallop powder and 5 to 15% (V/V) nitric acid aqueous solution into the mixture composed of 1.0 to 10:1, knead and extrude into a strip, dry at 80 to 120°C, and dry at 450°C. Roast at ~600°C for 2 to 8 hours to prepare sodium-type ZSM-5 strip catalyst; then, prepare 0.2-0.8 mol/liter ammonium nitrate aqueous solution, according to the catalyst weight: the volume of ammonium nitrate aqueous solution is equal to 1-10, and the sodium-type ZSM-5 ZSM-5 strip-shaped catalyst is immersed in it, the immersion temperature is 20-50°C, the immersion time is 1-10 hours, dried at 80-120°C, and roasted at 450-600°C for 2-8 hours to obtain a hydrogen-type ZSM-5 catalyst; Prepare 0.2-0.8 mol/L nitric acid aqueous solution, according to catalyst weight: the volume of ammonium nitrate aqueous solution is equal to 1-10, immerse hydrogen-type ZSM-5 catalyst in it for acid pore expansion, immersion temperature 20-50℃, immersion time 15-30 hours , dried at 80-120°C, calcined at 450-600°C for 2-8 hours to obtain the hydrogen-type ZSM-5 catalyst precursor; then, treated with water vapor or ammonia water vapor at high temperature; finally, impregnated the IIB group The compound of element zinc, the compound of IIIB group element lanthanum, the compound of VIB group element molybdenum, the compound of VIII group element cobalt or nickel, the compound of alkali metal element magnesium, and the compound of non-metal element phosphorus are modified separately or in combination, after drying, The modified composite sulfur-tolerant industrial catalyst was prepared by temperature-programmed calcination. 5. according to the preparation method of the described sulfur-resistant industrial catalyst of claim 4, it is characterized in that steam treatment condition is normal pressure, temperature is 300～600 ℃, with the steam treatment 1～20 of weight space velocity 0.2～ ^5h Hours; when treated with ammonia water vapor, the concentration of ammonia water is 0.1-1.0 mol/liter, and the pressure, temperature, and time are the same as those for water vapor treatment. 6. according to the preparation method of the described sulfur-resistant industrial catalyst of claim 4, it is characterized in that wet impregnation modification is that zinc nitrate, lanthanum nitrate, cobalt nitrate, nickel nitrate, ammonium molybdate, magnesium acetate or ammonium phosphate are made into ～2.0 mol/liter aqueous solution, according to catalyst weight: aqueous solution volume ratio is 1～10, impregnated at 20～50℃ for 1～10 hours, loaded on the hydrogen type ZSM-5 catalyst treated with water vapor, and then at 80～ Dry at 120°C, raise the temperature from room temperature to 400-470°C at a rate of 2-7°C/min, keep it warm for 1-3 hours, then raise it to 470-520°C at a rate of 1-3°C/min, keep it warm 1 to 3 hours, and finally raised to 520 to 550°C at a rate of 1 to 3°C/min, kept at a temperature of 2 to 6 hours, and then lowered to room temperature to obtain a modified composite sulfur-resistant industrial catalyst.