CN111097500B

CN111097500B - Supported catalyst, preparation method and application thereof, and method for hydrotreating diesel fraction

Info

Publication number: CN111097500B
Application number: CN201811261629.6A
Authority: CN
Inventors: 刘凌涛; 朱振兴; 张同旺; 朱丙田; 韩颖; 何金龙
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2018-10-26
Filing date: 2018-10-26
Publication date: 2023-05-05
Anticipated expiration: 2038-10-26
Also published as: CN111097500A

Abstract

The invention relates to the field of catalyst preparation and application, and discloses a supported catalyst, a preparation method and application thereof and a method for hydrotreating diesel fraction, wherein the catalyst comprises the following components: (1) 10-75 wt% of a binder; (2) 5-50 wt% of a sulfur absorbing component; (3) 1-30 wt% of an acidic molecular sieve; and (4) 1 to 30% by weight of a carbide of at least one metal element selected from group VB and group VIB. The supported catalyst provided by the invention can obviously improve the selectivity of BTX in the diesel fraction conversion process when being used for the hydrotreatment of diesel fraction.

Description

Supported catalyst, preparation method and application thereof, and method for hydrotreating diesel fraction

Technical Field

The invention relates to the field of catalyst preparation and application, in particular to a supported catalyst, a method for preparing the supported catalyst, the supported catalyst prepared by the method, application of the supported catalyst in the hydrotreatment of diesel oil fraction and a method for hydrotreatment of the diesel oil fraction.

Background

On the one hand, with the gradual decrease of the sales rate of the automobiles and the continuous increase of the proportion of the electric automobiles in China, the fuel oil demand increase rate of the automobiles is gradually reduced and even the demand is reduced. On the other hand, with the development of fuel oil heaviness and the rapid development of processing ability of catalytic cracking technology, the yield of diesel oil fraction increases year by year and the quality becomes poor. The diesel fraction has higher aromatic hydrocarbon, nitrogen, sulfur and olefin content, and poorer cetane number and stability. The total content of aromatic hydrocarbon in the diesel fraction reaches 70-80%, wherein the total content of the dicyclic and above aromatic hydrocarbon exceeds 50% of the total content of the aromatic hydrocarbon.

Therefore, it is urgent to find a new diesel fraction treatment method for increasingly stringent environmental requirements and diesel excess market conditions.

The conventional diesel fraction hydrofining process can effectively remove sulfur, nitrogen and other impurities. However, the cetane number is limited to be improved, the hydrogen consumption is high, the reaction pressure is high, the pressure is generally more than 10MPa, and the problems of high investment, high operation cost and the like exist.

CN1903993a discloses a hydrocracking process for producing high-quality ethylene feedstock in high yield, by hydrofining and hydrocracking serial processes, producing naphtha fraction, diesel fraction and tail oil fraction.

CN101210198A discloses a hydrogenation method for high-quality diesel oil and high-quality reforming raw materials, after mixing diesel oil and/or light wax oil raw materials with hydrogen, contacting and reacting with a hydrofining catalyst and a hydrocracking catalyst in sequence, without intermediate separation, the products are naphtha fraction, kerosene fraction, diesel oil fraction and tail oil fraction. The kerosene and/or tail oil fraction may be directly withdrawn or partially recycled.

CN1955263a discloses a method for processing poor quality catalytic cracking diesel oil and hydrocracking raw material in a combined way, and can effectively produce high quality chemical raw material through the optimized combination of different processes. But the production flexibility is poor and it is difficult to cope with rapid changes in market demand.

CN101987971a discloses a method for producing high-octane gasoline from poor diesel oil, in which the diesel oil raw oil and hydrogen are hydrofined in a first reaction zone, then enter a second reaction zone without separation for hydrocracking, and low-sulfur high-octane gasoline is obtained by controlling the reaction depth, and at the same time, low-sulfur clean diesel oil blending component is obtained.

CN104560164a discloses a method for producing high octane gasoline components or aromatics from diesel fractions. The method comprises the steps of firstly enabling inferior diesel oil to enter a hydrofining reaction area, enabling the inferior diesel oil to contact and react with a refining catalyst, then enabling the inferior diesel oil to enter a hydro-upgrading reaction area, enabling the inferior diesel oil to contact and react with a first hydro-upgrading catalyst and a second hydro-upgrading catalyst in sequence, and cooling and separating products to obtain hydrogen-rich gas and liquid products. The method provided by the invention uses the inferior diesel oil fraction as a raw material, can produce high-octane gasoline, and the aromatic hydrocarbon content in the high-octane gasoline fraction can reach more than 40%. However, the process has the defects of long flow and high operation cost.

Disclosure of Invention

The invention aims to provide a catalyst which can be used for the hydrotreatment of a diesel fraction so as to improve the selectivity of BTX in the conversion process of the diesel fraction.

In order to achieve the above object, a first aspect of the present invention provides a supported catalyst comprising, based on the total weight of the catalyst:

(1) 10-75% by weight of a binder;

(2) 5-50 wt% of a sulfur absorbing component;

(3) 1-30 wt% of an acidic molecular sieve; and

(4) 1 to 30% by weight of a carbide of at least one metal element selected from group VB and group VIB,

wherein the sulfur absorbing component is at least one of oxides of non-noble metal elements selected from group IIB, group VB, group VIB and group VIII capable of forming sulfides with sulfur.

In a second aspect, the present invention provides a method of preparing a supported catalyst, the method comprising:

1) Mixing an acidic molecular sieve, a binder precursor and a sulfur absorbing component in the presence of an acidic aqueous solution to slurry to obtain a slurry;

2) Subjecting the slurry to spray drying to obtain shaped particles;

3) Contacting the shaped particles with a salt solution containing at least one metal element selected from group VB and group VIB to obtain a supported crude product;

4) Sequentially drying, roasting, reducing and carbonizing the loaded crude product;

wherein the sulfur absorbing component is at least one of oxides of non-noble metal elements selected from group IIB, group VB, group VIB and group VIII capable of forming sulfides with sulfur;

the binder precursor is at least one substance capable of forming a binder in the finished catalyst product;

the binder precursor, the sulfur absorbing component, the acidic molecular sieve and the salt solution are used in amounts such that they comprise, based on the total weight of the catalyst prepared:

(1) 10-75% by weight of a binder;

(2) 5-50 wt% of a sulfur absorbing component;

(3) 1-30 wt% of an acidic molecular sieve; and

(4) 1-30 wt% of a carbide of at least one metal element selected from group VB and group VIB.

A third aspect of the present invention provides a supported catalyst prepared by the method of the second aspect.

A fourth aspect of the present invention provides the use of a supported catalyst as described in the first and/or third aspects above in the hydroprocessing of a diesel fraction.

In a fifth aspect the present invention provides a process for the hydroprocessing of a diesel fraction, the process comprising: the diesel fraction is introduced into the reaction unit with a hydrogen-containing stream to be contacted with a catalyst, wherein the supported catalyst is the supported catalyst according to the first and/or third aspect.

The supported catalyst provided by the invention can obviously improve the selectivity of BTX in the diesel fraction conversion process when being used for the hydrotreatment of diesel fraction.

Detailed Description

The endpoints and any values of the ranges disclosed herein are not limited to the precise range or value, and are understood to encompass values approaching those ranges or values. For numerical ranges, one or more new numerical ranges may be found between the endpoints of each range, between the endpoint of each range and the individual point value, and between the individual point value, in combination with each other, and are to be considered as specifically disclosed herein.

As described above, the first aspect of the present invention provides a supported catalyst comprising, based on the total weight of the catalyst:

(1) 10-75% by weight of a binder;

(2) 5-50 wt% of a sulfur absorbing component;

(3) 1-30 wt% of an acidic molecular sieve; and

Preferably, the sulfur absorbing component is at least one of zinc oxide, iron oxide, cobalt oxide; more preferably, the sulfur absorbing component is zinc oxide. The inventors of the present invention have found that, in particular when the sulfur absorbing component is zinc oxide, the supported catalyst of the present invention is able to more significantly increase the selectivity of BTX in the conversion of diesel fraction when used in the hydroprocessing of diesel fraction.

Preferably, the sulfur absorbing component is present in an amount of 10 to 40 wt.% based on the total weight of the catalyst.

Preferably, the binder is present in an amount of 20 to 60 wt.%, based on the total weight of the catalyst.

The binder is one or more of heat-resistant inorganic oxides, preferably, the binder is at least one of alumina, silica and amorphous silica-alumina; more preferably the binder is alumina and/or silica.

Preferably, the acidic molecular sieve is at least one selected from the group consisting of a Y-type molecular sieve, a USY-type molecular sieve, an octahedral molecular sieve, a mercerized molecular sieve, an L-type molecular sieve, an omega molecular sieve, a beta molecular sieve, ZSM-5, a SAPO molecular sieve, and an MCM-41 mesoporous molecular sieve.

According to a preferred embodiment, the acidic molecular sieve is a Y-type molecular sieve and/or a beta molecular sieve.

Preferably, the acidic molecular sieve is in a weight ratio of (0.5-0.8): 1 and a beta molecular sieve.

Preferably, the carbide content is from 5 to 25% by weight, based on the total weight of the catalyst.

Particularly preferably, the carbide is at least one selected from the group consisting of vanadium carbide, molybdenum carbide, and tungsten carbide.

Preferably, the catalyst is microspheroidal and has an average particle size of from 20 to 200 microns.

As previously described, a second aspect of the present invention provides a method of preparing a supported catalyst, the method comprising:

2) Subjecting the slurry to spray drying to obtain shaped particles;

(1) 10-75% by weight of a binder;

(2) 5-50 wt% of a sulfur absorbing component;

(3) 1-30 wt% of an acidic molecular sieve; and

According to a preferred embodiment, one of the objects of the second aspect of the present invention is to prepare a supported catalyst as described in the first aspect of the present invention, and therefore the whole of the first aspect of the present invention is incorporated into the second aspect of the present invention without being repeated in the second aspect, and the person skilled in the art shall not be construed as limiting the present invention.

Preferably, the binder precursor is selected from at least one of hydrated alumina, alumina sol, silica gel, water glass, and silica alumina sol.

Preferably, the hydrated alumina is at least one selected from boehmite, pseudo-boehmite, alumina trihydrate and amorphous aluminum hydroxide.

The sulfur absorbing component of the present invention may be used directly as an oxide powder or as a previously prepared oxide slurry.

Preferably, in step 1), the acidic aqueous solution is used in an amount such that the pH of the slurry is between 1 and 6, more preferably between 1.5 and 5.

In the present invention, the acidic aqueous solution may be one or more of inorganic acid and/or organic acid soluble in water, and may be one or more of hydrochloric acid, nitric acid, phosphoric acid and acetic acid, for example.

Preferably, the spray drying conditions include: the pressure is 2-15 MPa, the inlet temperature is 300-490 ℃, and the outlet temperature is 110-180 ℃.

In step 3), the method of contacting the shaped particles with a salt solution containing at least one metal element selected from group VB and group VIB may be a dipping or precipitation method. The impregnation method is to impregnate the roasted carrier with a salt solution containing at least one metal element selected from the group consisting of the VB group and the VIB group; the precipitation method is to mix a salt solution containing at least one metal element selected from the group consisting of the group VB and the group VIB with a carrier, and then add ammonia water to precipitate a metal compound on the carrier to form an impregnated composite, wherein the metal compound is a substance which can be converted into a metal oxide under the calcining condition. The metal compound may be selected from the group consisting of acetates, carbonates, nitrates, sulfates, thiocyanates, metal acids, metal salts and oxides of metals, mixtures of two or more thereof, and the like.

Preferably, in step 4), the drying conditions include: the temperature is 90-300 ℃ and the time is 0.5-24h; more preferably, the drying conditions include: the temperature is 100-200deg.C, and the time is 1-8h.

Preferably, the roasting conditions include: the temperature is 350-800 ℃ and the time is 0.5-8h; more preferably, the conditions for firing include: the temperature is 450-750 ℃ and the time is 1-5h.

The calcination of the present invention may be performed in the presence of an oxygen-containing gas, such that volatile materials are removed and the metal carbide precursor is converted to a metal oxide, resulting in a catalyst precursor.

Preferably, the reductive carbonization is performed in the presence of a reducing gas and a hydrocarbon gas, and the hydrocarbon gas is contained in an amount of 1 to 95% by volume. More preferably, the hydrocarbon gas is present in an amount of 5 to 60% by volume. The inventors of the present invention found that when the hydrocarbon gas content in the reductive carbonization process is 5 to 60% by volume, the selectivity of BTX in the treatment of diesel fraction is significantly higher for the obtained catalyst.

Preferably, the hydrocarbon gas is selected from at least one of methane, ethane, ethylene, propane, propylene; more preferably, the hydrocarbon gas is methane.

Preferably, the conditions for reductive carbonization include: the temperature is 150-900 ℃ and the time is 0.5-24h. More preferably, the time for reductive carbonization is 1 to 12 hours. More preferably, the conditions for reductive carbonization include: heating the roasted loaded crude product from a first temperature of 150-300 ℃ to a second temperature of 500-900 ℃ at a speed of 0.5-20 ℃/min, and then preserving the temperature of the loaded crude product at the second temperature for more than 0.5 h.

Preferably, in step 2), the spray-drying conditions are controlled such that the prepared supported catalyst is microspheroidal and has an average particle size of 20 to 200 microns.

As previously described, a third aspect of the present invention provides a supported catalyst prepared by the method of the second aspect.

As previously mentioned, a fourth aspect of the present invention provides the use of a supported catalyst as described in the first and/or third aspects above in the hydroprocessing of a diesel fraction.

As previously described, a fifth aspect of the present invention provides a method of hydrotreating a diesel fraction, the method comprising: the diesel fraction is introduced into the reaction unit with a hydrogen-containing stream to be contacted with a catalyst, wherein the supported catalyst is the supported catalyst according to the first and/or third aspect.

The method for the hydro-treating the diesel fraction enables polycyclic aromatic hydrocarbon in the diesel fraction to be converted into alkylbenzene products, and simultaneously adsorbs and fixes impurities such as sulfur, nitrogen and the like on the supported catalyst, thereby improving the selectivity of BTX in the diesel fraction conversion process.

The process of the present invention is not particularly limited to the reaction unit, and may be, for example, a circulating fluidized bed reactor.

Preferably, the conditions of the contact reaction include: the reaction temperature is 250-550 ℃, the reaction pressure is 0.5-8MPa, and the weight hourly space velocity of the diesel fraction is 0.05-10h ^-1 . More preferably, the conditions of the contact reaction include: the reaction temperature is 300-500 ℃, the reaction pressure is 1-5MPa, and the weight hourly space velocity of the diesel fraction is 0.1-5h ^-1 。

Preferably, the volume ratio of the hydrogen-containing stream to the diesel fraction is (10-2000): 1, more preferably (50-1000): 1.

particularly preferably, the hydrogen-containing stream of the present invention is a hydrogen-containing gas.

According to a preferred embodiment, the method of the invention further comprises: and contacting the catalyst subjected to the contact reaction with an oxygen-containing gas to perform regeneration treatment, and recycling the regenerated catalyst obtained after the regeneration treatment for the contact reaction.

The oxygen-containing gas may be air or a mixed gas of oxygen and air.

Preferably, the conditions of the regeneration treatment include: the regeneration temperature is 200-700 ℃, and the pressure (gauge pressure) is 0-3.0MPa; more preferably, the conditions of the regeneration treatment include: the temperature is 300-600 ℃, and the pressure (gauge pressure) is 0-1.0MPa.

Preferably, the sulfur content in the diesel fraction does not exceed 1500mg/kg and the nitrogen content does not exceed 1000mg/kg. More preferably, the sulfur content in the diesel fraction is not more than 800mg/kg and the nitrogen content is not more than 800mg/kg.

Preferably, the diesel fraction is at least one of catalytic cracking diesel, straight-run diesel, coker diesel and visbreaking diesel.

Preferably, the diesel fraction has a distillation range of 180-390 ℃.

The supported catalyst provided by the invention has excellent selective conversion performance, and can improve the BTX selectivity in diesel fraction products.

The invention will be described in detail below by way of examples. In the following examples, all the raw materials used are commercially available products unless otherwise specified.

The properties of the feedstock diesel fraction used below are shown in table 1. The results of properties of the products obtained in Table 2 were obtained by gas chromatography and ultraviolet fluorescence element analyzer. The chemical composition of the following catalyst precursor was measured using XRD.

TABLE 1

	Catalytic diesel fuel feedstock
		Density/kg.m ^-3	934
Distillation range/. Degree.C	185～352
		Initial point/. Degree.C	185
50％/℃	260
		End point/. Degree.C	352
Sulfur content/. Mu. g.g ^-1	830
		Nitrogen content/. Mu. g.g ^-1	530
Naphthene amount/wt%	4.2
		Total aromatic hydrocarbon content/wt%	81
Monocyclic and bicyclic aromatic hydrocarbon content/wt%	72

Example 1

Mixing 1.5kg of alumina, 1.2kg of beta molecular sieve and 2.0kg of rectorite under stirring, adding 4.0kg of deionized water, uniformly mixing, adding 30 wt% of hydrochloric acid, stirring and acidifying to enable the pH value of the slurry to be 4.5, heating to 80 ℃ after 1h, and aging for 2h to obtain the adhesive slurry.

1.5kg of zinc oxide powder and 5kg of deionized water were mixed and stirred for 120min to obtain zinc oxide slurry.

The zinc oxide slurry and the binder slurry were mixed and stirred for 2 hours to obtain a carrier slurry.

The carrier slurry is spray dried by a spray dryer, the spray drying pressure is 9MPa, the inlet temperature is about 450 ℃, and the outlet temperature is about 150 ℃. The support microspheres obtained by spray drying were dried at 160℃for 1 hour and then calcined at 625℃for 2 hours to obtain a catalyst support.

6.2kg of the catalyst carrier was impregnated with 1.0kg of ammonium metatungstate (tungsten trioxide content: 83% by weight) and 1.10kg of deionized water solution in two spray patterns, and the resultant mixture was dried at 170℃for 2 hours and then calcined at 625℃for 1 hour to obtain a catalyst precursor.

The chemical composition of the catalyst precursor was measured as: the tungsten trioxide content was 11.9 wt.%, the alumina binder was 21.2 wt.%, the rectorite was 28.6 wt.%, the zinc oxide was 21.2 wt.%, and the beta molecular sieve was 17.1 wt.%.

Then, the volume flow ratio is 1:1 in the atmosphere of hydrogen and methane, heating from 200 ℃ to 750 ℃ at 2 ℃ per minute, then keeping at 750 ℃ for 2 hours, and sieving to obtain the microsphere supported catalyst with the average particle size of 80 microns, which is denoted as a catalyst M1.

The diesel fraction shown in table 1 was introduced into a reaction unit with hydrogen to perform a contact reaction with the catalyst M1, the stream obtained after the contact was subjected to gas-liquid separation, and the catalyst after the contact was contacted with oxygen to perform a regeneration treatment, and the conditions of the contact reaction, the conditions of the regeneration treatment, and the properties of the obtained product are shown in table 2.

Comparative example 1

The preparation method of reference example 1 is different in that:

the catalyst precursor was prepared using 1.0kg of nickel nitrate instead of 1.0kg of ammonium metatungstate in example 1.

The chemical composition of the catalyst precursor was measured as: the nickel oxide content was 11.9 wt.%, the alumina binder was 21.2 wt.%, the rectorite was 28.6 wt.%, the zinc oxide was 21.2 wt.%, and the beta molecular sieve was 17.1 wt.%.

Then, the volume flow ratio is 1:1 in the atmosphere of hydrogen and methane, heating from 200 ℃ to 750 ℃ at 2 ℃ per minute, and keeping at 750 ℃ for 2 hours to obtain the supported catalyst, namely the catalyst B1.

The diesel fraction shown in table 1 was introduced into a reaction unit with hydrogen to perform a contact reaction with catalyst B1, the stream obtained after the contact was subjected to gas-liquid separation, and the catalyst after the contact was contacted with oxygen to perform a regeneration treatment, and the conditions of the contact reaction, the conditions of the regeneration treatment, and the properties of the obtained product are shown in table 2.

Comparative example 2

The preparation method of reference example 1 is different in that:

the supported catalyst, designated as catalyst B2 (i.e., the catalyst of this comparative example was reduced only without carbonization) was obtained by heating from 200 ℃ to 750 ℃ at 2 ℃ per minute in a hydrogen atmosphere and then holding at 750 ℃ for 2 hours.

The diesel fraction shown in table 1 was introduced into a reaction unit with hydrogen to perform a contact reaction with catalyst B2, the stream obtained after the contact was subjected to gas-liquid separation, and the catalyst after the contact was contacted with oxygen to perform a regeneration treatment, and the conditions of the contact reaction, the conditions of the regeneration treatment, and the properties of the obtained product are shown in table 2.

Example 2

Mixing 1.3kg of silicon oxide, 1.2kg of Y molecular sieve and 2.7kg of rectorite under stirring, adding 4.0kg of deionized water, uniformly mixing, adding 30 wt% of hydrochloric acid, stirring and acidifying to enable the pH value of the slurry to be 3.5, heating to 80 ℃ after 1h, and aging for 2h to obtain the adhesive slurry.

0.8kg of zinc oxide powder and 5kg of deionized water were mixed and stirred for 120min to obtain zinc oxide slurry.

The carrier slurry is spray dried by a spray dryer, the spray drying pressure is 8.5MPa, the inlet temperature is about 430 ℃, and the outlet temperature is about 160 ℃. The support microspheres obtained by spray drying were dried at 160℃for 1 hour and then calcined at 625℃for 2 hours to obtain a catalyst support.

6.0kg of the catalyst carrier was impregnated with 1.2kg of ammonium metatungstate (tungsten trioxide content: 83% by weight) and 1.10kg of deionized water solution in two spray patterns, and the resultant mixture was dried at 200℃for 1 hour and then calcined at 625℃for 1 hour to obtain a catalyst precursor.

The chemical composition of the catalyst precursor was measured as: the tungsten trioxide content was 14.3 wt.%, the alumina binder was 18.5 wt.%, the rectorite was 38.6 wt.%, the zinc oxide was 11.4 wt.%, and the beta molecular sieve was 17.1 wt.%.

Then the volume flow ratio is 2:1 in the atmosphere of hydrogen and ethane, heating from 200 ℃ to 650 ℃ at 4 ℃ per minute, then keeping for 4 hours at 650 ℃, and sieving to obtain the microsphere supported catalyst with the average particle size of 80 microns, which is denoted as a catalyst M2.

The diesel fraction shown in table 1 was introduced into a reaction unit with hydrogen to perform a contact reaction with catalyst M2, the stream obtained after the contact was subjected to gas-liquid separation, and the catalyst after the contact was contacted with oxygen to perform a regeneration treatment, and the conditions of the contact reaction, the conditions of the regeneration treatment, and the properties of the obtained product are shown in table 2.

Example 3

Mixing 1.5kg of alumina, 0.8kg of beta molecular sieve, 0.4kg of Y molecular sieve and 2.0kg of montmorillonite under stirring, adding 4.0kg of deionized water, uniformly mixing, adding 30 wt% of hydrochloric acid, stirring and acidifying to enable the pH value of the slurry to be 4, heating to 80 ℃ after 1h, and aging for 2h to obtain the adhesive slurry.

1.5kg of iron oxide powder, 5kg of deionized water and the binder slurry were mixed and stirred for 2 hours to obtain a carrier slurry.

The carrier slurry is subjected to spray drying by a spray dryer, the spray drying pressure is 8.7MPa, the inlet temperature is about 485 ℃, and the outlet temperature is about 143 ℃. The support microspheres obtained by spray drying were dried at 160℃for 1 hour and then calcined at 625℃for 2 hours to obtain a catalyst support.

6.2kg of the catalyst carrier was impregnated with 1.5kg of ammonium tungstate (tungsten trioxide content: 83 wt%) and 1.10kg of deionized water solution in two spray processes, and the resultant mixture was dried at 170℃for 2 hours and then calcined at 600℃for 2 hours to obtain a catalyst precursor.

The chemical composition of the catalyst precursor was measured as: the tungsten trioxide content was 16.7 wt.%, the alumina content was 20.1 wt.%, the beta molecular sieve content was 10.7 wt.%, the Y molecular sieve content was 5.4 wt.%, the montmorillonite content was 26.9 wt.%, and the iron oxide content was 20.1 wt.%.

Then the volume flow ratio is 2:3 in the atmosphere of hydrogen and methane, heating from 200 ℃ to 700 ℃ at 3 ℃ per minute, then keeping at 700 ℃ for 2.5 hours, and sieving to obtain the microsphere supported catalyst with the average particle size of 80 microns, which is denoted as a catalyst M3.

The diesel fraction shown in table 1 was introduced into a reaction unit with hydrogen to perform a contact reaction with catalyst M3, the stream obtained after the contact was subjected to gas-liquid separation, and the catalyst after the contact was contacted with oxygen to perform a regeneration treatment, and the conditions of the contact reaction, the conditions of the regeneration treatment, and the properties of the obtained product are shown in table 2.

Example 4

The preparation method of reference example 1 is different in that:

in this embodiment, the volume flow ratio is 7:3 in the atmosphere of hydrogen and methane, heating from 200 ℃ to 750 ℃ at 2 ℃ per minute, then keeping at 750 ℃ for 2 hours, and sieving to obtain the microsphere supported catalyst with the average particle size of 80 microns, which is denoted as a catalyst M4.

The diesel fraction shown in table 1 was introduced into a reaction unit with hydrogen to perform a contact reaction with catalyst M4, the stream obtained after the contact was subjected to gas-liquid separation, and the catalyst after the contact was contacted with oxygen to perform a regeneration treatment, and the conditions of the contact reaction, the conditions of the regeneration treatment, and the properties of the obtained product are shown in table 2.

Example 5

The preparation method of reference example 1 is different in that:

1.6kg of cobalt oxide powder was used instead of 1.5kg of zinc oxide powder in example 1. The remainder was the same as in example 1, and a microspheroidal supported catalyst having an average particle diameter of 80 microns was obtained and designated as catalyst M5.

The diesel fraction shown in table 1 was introduced into a reaction unit with hydrogen to perform a contact reaction with catalyst M5, the stream obtained after the contact was subjected to gas-liquid separation, and the catalyst after the contact was contacted with oxygen to perform a regeneration treatment, and the conditions of the contact reaction, the conditions of the regeneration treatment, and the properties of the obtained product are shown in table 2.

TABLE 2

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"L" in Table 2 represents an example, and "DL" represents a comparative example.

As can be seen from the results of Table 2, the selectivity of BTX is significantly higher when the diesel fraction is treated with the supported catalyst provided by the present invention.

The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, a number of simple variants of the technical solution of the invention are possible, including combinations of the individual technical features in any other suitable way, which simple variants and combinations should likewise be regarded as being disclosed by the invention, all falling within the scope of protection of the invention.

Claims

1. Use of a supported catalyst in the hydroprocessing of a diesel fraction, the use comprising: introducing the diesel fraction and the hydrogen-containing stream into a reaction unit to perform a contact reaction with a supported catalyst, wherein the supported catalyst comprises, based on the total weight of the supported catalyst:

(1) 10-75% by weight of a binder;

(2) 5-50 wt% of a sulfur absorbing component;

(3) 1-30 wt% of an acidic molecular sieve; and

the method for preparing the supported catalyst comprises the following steps:

1) Mixing an acidic molecular sieve, a binder precursor and a sulfur absorbing component in the presence of an acidic aqueous solution to slurry to obtain a slurry; wherein the binder precursor is at least one substance capable of forming a binder in the finished catalyst product;

2) Subjecting the slurry to spray drying to obtain shaped particles;

4) And drying, roasting and reducing carbonization are sequentially carried out on the loaded crude product.

2. The use according to claim 1, wherein the sulfur absorbing component is at least one of zinc oxide, iron oxide, cobalt oxide.

3. Use according to claim 2, wherein the sulphur absorbing component is zinc oxide.

4. Use according to any one of claims 1 to 3, wherein the sulfur-absorbing component is present in an amount of 10 to 40% by weight, based on the total weight of the supported catalyst.

5. Use according to any one of claims 1 to 3, wherein the binder is present in an amount of 20 to 60% by weight, based on the total weight of the supported catalyst.

6. Use according to any one of claims 1-3, wherein the binder is selected from at least one of alumina, silica and amorphous silica alumina.

7. The use according to any one of claims 1-3, wherein the acidic molecular sieve is selected from at least one of a Y-type molecular sieve, a mercerized molecular sieve, an L-type molecular sieve, an Ω -molecular sieve, a β -molecular sieve, a ZSM-5 molecular sieve, a SAPO molecular sieve, and an MCM-41 mesoporous molecular sieve.

8. Use according to claim 7, wherein the acidic molecular sieve is a Y-type molecular sieve and/or a beta molecular sieve.

9. Use according to any one of claims 1 to 3, wherein the carbide content is 5 to 25% by weight, based on the total weight of the catalyst.

10. Use according to any one of claims 1-3, wherein the carbide is selected from at least one of vanadium carbide, molybdenum carbide, tungsten carbide.

11. The use according to claim 1, wherein the binder precursor is selected from at least one of hydrated alumina, alumina sol, silica gel, water glass and silica alumina sol.

12. The use according to claim 11, wherein the hydrated alumina is selected from at least one of boehmite, pseudo-boehmite, alumina trihydrate and amorphous aluminum hydroxide.

13. Use according to any one of claims 1, 11-12, wherein in step 1) the acidic aqueous solution is used in an amount such that the pH of the slurry is between 1 and 6.

14. Use according to claim 13, wherein in step 1) the acidic aqueous solution is used in an amount such that the pH of the slurry is between 1.5 and 5.

15. The use according to any one of claims 1, 11-12, wherein in step 4), the drying conditions comprise: the temperature is 90-300 ℃ and the time is 0.5-24h.

16. The use according to claim 15, wherein in step 4) the drying conditions comprise: the temperature is 100-200deg.C, and the time is 1-8h.

17. The use according to any one of claims 1, 11-12, wherein in step 4) the firing conditions comprise: the temperature is 350-800 ℃ and the time is 0.5-8h.

18. The use of claim 17, wherein in step 4) the firing conditions include: the temperature is 450-750 ℃ and the time is 1-5h.

19. Use according to any one of claims 1, 11-12, wherein in step 4) the reductive carbonization is performed in the presence of a reducing gas and a hydrocarbon gas, and the hydrocarbon gas is present in an amount of 1-95 vol%.

20. Use according to claim 19, wherein the hydrocarbon gas content is 5-60% by volume.

21. The use of claim 19, wherein the hydrocarbon gas is selected from at least one of methane, ethane, ethylene, propane, propylene.

22. The use according to any one of claims 1, 11-12, wherein in step 4) the conditions for reductive carbonization comprise: the temperature is 150-900 ℃ and the time is 0.5-24h.

23. The use according to any one of claims 1, 11-12, wherein in step 4) the conditions for reductive carbonization comprise: heating the roasted loaded crude product from a first temperature of 150-300 ℃ to a second temperature of 500-900 ℃ at a speed of 0.5-20 ℃/min, and then preserving the temperature of the loaded crude product at the second temperature for more than 0.5 h.

24. The use according to any one of claims 1, 11-12, wherein in step 2) the spray drying conditions are controlled such that the supported catalyst is prepared as microspheres and has an average particle size of 20-200 microns.

25. The use of claim 1, wherein the conditions of the contact reaction comprise: the reaction temperature is 250-550 ℃, the reaction pressure is 0.5-8MPa, and the weight hourly space velocity of the diesel fraction is 0.05-10h ^-1 。

26. The use of claim 25, wherein the conditions of the contact reaction comprise: the reaction temperature is 300-500 ℃, the reaction pressure is 1-5MPa, and the weight hourly space velocity of the diesel fraction is 0.1-5h ^-1 。

27. Use according to any one of claims 1, 25-26, wherein the volume ratio of the hydrogen-containing stream to the diesel fraction is (10-2000): 1.

28. use according to claim 27, wherein the volume ratio of the hydrogen-containing stream to the diesel fraction is (50-1000): 1.

29. the use of any one of claims 1, 25-26, wherein the method further comprises: and contacting the catalyst subjected to the contact reaction with an oxygen-containing gas to perform regeneration treatment, and recycling the regenerated catalyst obtained after the regeneration treatment for the contact reaction.

30. The use of claim 29, wherein the regeneration process conditions include: the regeneration temperature is 200-700 ℃ and the pressure is 0-3.0MPa.

31. The use of claim 30, wherein the regeneration process conditions include: the regeneration temperature is 300-600 ℃ and the pressure is 0-1.0MPa.

32. Use according to any one of claims 1, 25-26, wherein the sulphur content in the diesel fraction does not exceed 1500mg/kg and the nitrogen content does not exceed 1000mg/kg.

33. The use according to any one of claims 1, 25-26, wherein the diesel fraction is at least one of a catalytically cracked diesel, a straight run diesel, a coker diesel and a visbreaker diesel.

34. The use according to any one of claims 1, 25-26, wherein the diesel fraction has a distillation range of 180-390 ℃.