A hydrogenation catalyst for bicyclic aromatic hydrocarbon-rich feedstock oil, its preparation method and application

Abstract

The present disclosure relates to a hydrogenation catalyst for raw oil rich in bicyclic aromatic hydrocarbons, and a preparation method and application thereof, the hydrogenation catalyst comprising a carrier and an active metal component supported on the carrier; the active metal component comprising a Group VIII metal element and a Group VIB metal element; the carrier consisting of an acidic component and a matrix, the acidic component being a molecular sieve with a BX value greater than 1; wherein the BX value of a molecular sieve to be tested is defined as the ratio of the adsorption amount of benzene to the adsorption amount of butylbenzene of the molecular sieve to be tested. The present disclosure realizes screening through the BX value, and the catalyst with a new type of molecular sieve or related combination as the acidic component can improve the BTX product selectivity of raw oil with a high content of bicyclic aromatic hydrocarbons.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of catalysts, in particular, to a hydrogenation catalyst for feed oil rich in bicyclic aromatic hydrocarbons and a preparation method and application thereof. BACKGROUND

[0002] With the increasingly stringent standards for vehicle diesel emissions, the upper limit of the content of polycyclic aromatic hydrocarbons in high-quality diesel is increasingly stringent, and in the future, the total aromatic hydrocarbon content may be limited. The quality of catalytic cracking diesel fraction is increasingly deteriorating, and its characteristics of high aromatic content and low cetane number are no longer suitable as a diesel raw material. Based on the composition characteristics of catalytic diesel rich in bicyclic aromatic hydrocarbons and the characteristics of bicyclic aromatic hydrocarbon hydrocracking reaction, it can be considered to hydrogenate catalytic diesel rich in bicyclic aromatic hydrocarbons to prepare BTX, such as benzene, toluene, and xylene. In the prior art, the acid carrier has an important influence on the reaction, and Y and Beta type molecular sieve catalysts are reported more frequently, and the products are mainly gasoline, diesel or BTX.

[0003] Chinese patent document CN105457671 discloses a hydrocracking catalyst, a preparation method thereof and a hydrocracking reaction method. The hydrocracking catalyst comprises a carrier and an active component loaded on the carrier, wherein the active component is composed of molybdenum, cobalt and nickel, and the content of the molybdenum, the cobalt and the nickel is 3-20 wt%, 0.5-5 wt% and 0.1-1 wt% respectively, and the molar ratio of cobalt atoms to nickel atoms in the active component is 1-15:1; the carrier contains a solid acid component and an inorganic heat-resistant oxide, and the solid acid component is Y type molecular sieve or a mixture of Y type molecular sieve and amorphous silicon aluminum. The hydrocracking catalyst not only is not easy to accumulate carbon, but also can obtain a hydrocracking product with high aromatic content.

[0004] Chinese patent document CN105435837 discloses a hydrocracking catalyst, a preparation and application thereof. The catalyst contains a carrier containing a molecular sieve solid acid component, the molecular sieve solid acid component is a mixture containing MoBeta type zeolite and Y type molecular sieve, and the weight ratio of the MoBeta type zeolite to the Y type molecular sieve in the molecular sieve mixture is 9:1-1:9, wherein the n value of the MoBeta type zeolite is 0

[0005] From the above patent documents, it can be seen that the acid component of the existing catalyst is mainly Y type or Beta type catalyst, and the acid component of the existing catalyst still needs to be strengthened in improving the selectivity of BTX. SUMMARY

[0006] The purpose of the present disclosure is to provide a catalyst with high BTX selectivity.

[0007] To achieve the above-mentioned purpose, the first aspect of the present disclosure provides a hydrogenation catalyst for a raw oil rich in bicyclic aromatic hydrocarbons, the hydrogenation catalyst comprising a carrier and an active metal component supported on the carrier; the active metal component comprises a Group VIII metal element and a Group VIB metal element; the carrier is composed of an acidic component and a matrix, the acidic component being a molecular sieve with a BX value greater than 1; wherein the BX value of a certain to-be-tested molecular sieve is defined as the ratio of the adsorption amount of benzene to the adsorption amount of butylbenzene of the to-be-tested molecular sieve.

[0008] Optionally, the BX value of the molecular sieve is 1-100, preferably 1-10; optionally, the pore volume of the molecular sieve is 0.4-0.8 cm 3 / g, and the acid density is 0.8-2.5 μmol / m 2 .

[0009] Optionally, the content of the acidic component is 30-90% by weight, preferably 45-80% by weight, based on the total weight of the carrier; and the content of the matrix is 10-70% by weight, preferably 20-55% by weight, based on the total weight of the carrier.

[0010] Optionally, the hydrogenation cracking catalyst contains 1-10% by weight of Group VIII metal elements and 2-40% by weight of Group VIB metal elements, based on the total weight of the catalyst in terms of oxides; preferably, the hydrogenation cracking catalyst contains 1-6% by weight of Group VIII metal components and 5-25% by weight of Group VIB metal components.

[0011] Optionally, the molecular sieve is selected from at least one of PKU-16 molecular sieve, SCM-15 molecular sieve, ITQ-4 molecular sieve, JU-64 molecular sieve, Beryllophosphate-H molecular sieve and UCSB-10GaZn molecular sieve.

[0012] Optionally, the matrix is selected from at least one of alumina, silica and silica-alumina.

[0013] The second aspect of the present disclosure provides a method for preparing the above-mentioned hydrogenation catalyst, the method comprising:

[0014] S1, mixing the matrix and the molecular sieve, then kneading and extruding to obtain an extruded strip; performing first drying and first calcination on the extruded strip to obtain a carrier;

[0015] S2. Impregnating the support with an aqueous solution containing a compound of a Group VIII metal and a compound of a Group VIB metal to obtain an impregnated support; and subjecting the impregnated support to a second drying and activation treatment.

[0016] Optionally, the weight ratio of the matrix to the molecular sieve is 3-7:7-3.

[0017] Optionally, in step S1, the conditions for the first drying treatment include: a drying temperature of 80-300°C, preferably 100-200°C; a drying time of 1-12 hours, preferably 2-8 hours; the conditions for the first roasting include: a roasting temperature of 350-850°C, preferably 450-650°C; a roasting time of 1-12 hours, preferably 2-6 hours; in step S2, the conditions for the impregnation include: an impregnation temperature of 20-150°C, and an impregnation time of 1-6 hours; the conditions for the second drying include: a temperature of 100-300°C, preferably 100-200°C; a time of 2-8 hours; the conditions for the activation treatment include: a temperature of 250-650°C, preferably 300-500°C; a time of 1-12 hours, preferably 2-6 hours.

[0018] A third aspect of the present disclosure provides a method for hydrocracking a feedstock oil rich in bicyclic aromatics, comprising contacting the feedstock oil rich in bicyclic aromatics and hydrogen with the above-mentioned hydrogenation catalyst and performing a hydrocracking reaction.

[0019] Through the above technical solution, the present disclosure realizes screening through BX value and adopts a new type of molecular sieve or related combination as a catalyst of the acidic component, which can improve the selectivity of the BTX product of the feedstock oil with a dicyclic aromatic hydrocarbon content.

[0020] Other features and advantages of the present disclosure will be described in detail in the following detailed description. DETAILED DESCRIPTION

[0021] The following describes the specific embodiments of the present disclosure in detail. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present disclosure and are not intended to limit the present disclosure.

[0022] In a first aspect, the present disclosure provides a hydrogenation catalyst for a feedstock oil rich in bicyclic aromatic hydrocarbons, the hydrogenation catalyst comprising a carrier and an active metal component supported on the carrier; the active metal component comprising a Group VIII metal element and a Group VIB metal element; the carrier comprising an acidic component and a matrix, the acidic component being a molecular sieve having a BX value greater than 1; wherein the BX value of a molecular sieve to be tested is defined as the ratio of the amount of benzene adsorbed by the molecular sieve to be tested to the amount of butylbenzene adsorbed by the molecular sieve to be tested.

[0023] The catalyst of the present disclosure significantly improves the adsorption capacity of the catalyst for the reactants, the diffusion capacity of the intermediate products and the desorption capacity of the products by selecting the molecular sieve with high BX value, thereby improving the BTX selectivity. The catalyst of the present disclosure strengthens the side chain breaking reaction of long chain alkylbenzene by regulating the matching of the molecular sieve channel structure with the reaction intermediates and target products, thereby improving the yield of BTX products.

[0024] The BX value of the present disclosure is determined by the adsorption molar ratio test method, specifically: first, accurately measure benzene and butylbenzene (100 mL, room temperature) respectively, then add a certain amount of molecular sieve material (5 g), seal and stir under the protection of inert gas (N2) at 1 atm and 360°C for 10 hours, then filter, reconstitute the filtrate, cool to room temperature, and then measure the solution volume again with a measuring cylinder to obtain the adsorption volume difference ΔV 测试分子筛_丁基苯 , ΔV 测试分子筛_苯 , respectively. The calculation formula of BX value is:

[0025] BX = ΔV 测试分子筛_苯 / ΔV 测试分子筛_丁基苯

[0026] Wherein ΔV 测试分子筛_丁基苯 must be greater than 0.

[0027] In a preferred embodiment of the present disclosure, the BX value of the molecular sieve is 1-100, preferably 1-10; the pore volume of the molecular sieve in the present disclosure can be 0.4-0.8 cm 3 / g, and the acid density can be 0.8-2.5 μmol / m 2 .

[0028] According to the present disclosure, the content of the acidic component can be 30-90 wt%, preferably 45-80 wt%, based on the total weight of the carrier; the content of the matrix can be 10-70 wt%, preferably 20-55 wt%.

[0029] According to the present disclosure, the hydrocracking catalyst can contain 1-10 wt% of Group VIII metal elements and 2-40 wt% of Group VIB metal elements, based on the total weight of the catalyst in terms of oxides; preferably, the hydrocracking catalyst can contain 1-6 wt% of Group VIII metal components and 5-25 wt% of Group VIB metal components.

[0030] According to the present disclosure, the molecular sieve can be selected from at least one of PKU-16 molecular sieve, SCM-15 molecular sieve, ITQ-4 molecular sieve, JU-64 molecular sieve, Beryllophosphate-H molecular sieve and UCSB-10GaZn molecular sieve.

[0031] According to the present disclosure, the matrix can be selected from at least one of alumina, silica, and silica-alumina. The alumina described in the present disclosure is selected from one or more transition phase alumina selected from γ, η, θ, δ, and χ, and can also be one or more transition phase alumina selected from γ, η, θ, δ, and χ containing one or more additive components selected from silicon, titanium, magnesium, boron, zirconium, thorium, niobium, and rare earth elements, preferably γ-alumina and γ-alumina containing one or more additive components selected from silicon, phosphorus, titanium, magnesium, boron, zirconium, thorium, niobium, and rare earth elements. They can be commercially available products or obtained by any existing method. The silica-alumina preferably has a pseudo-boehmite structure, and can also be a commercially available product or prepared by any existing technology. For example, the Siral series of commercial silica-alumina produced by Condea, Germany, has a pseudo-boehmite structure and can be used in the present disclosure.

[0032] The catalysts provided herein can be used in any reactor sufficient to allow the feedstock to contact the catalyst under hydrogenation conditions, such as a fixed bed reactor, a moving bed reactor, or an ebullating bed reactor. Other hydrocarbon oil feedstocks can also be directly processed for hydrogenation.

[0033] A second aspect of the present disclosure provides a method for preparing the above-mentioned hydrogenation catalyst, the method comprising:

[0034] S1. Mixing the matrix and the molecular sieve, kneading and extruding to obtain an extruded strip; performing a first drying and a first calcination on the extruded strip to obtain a carrier;

[0035] S2. Impregnating the support with an aqueous solution containing a compound of a Group VIII metal and a compound of a Group VIB metal to obtain an impregnated support; and subjecting the impregnated support to a second drying and activation treatment.

[0036] According to the present disclosure, the weight ratio of the matrix to the molecular sieve may be 3-7:7-3.

[0037] According to the present disclosure, in step S1, the conditions for the first drying treatment may include: a drying temperature of 80-300°C, preferably 100-200°C; a drying time of 1-12 hours, preferably 2-8 hours; the conditions for the first roasting may include: a roasting temperature of 350-850°C, preferably 450-650°C; a roasting time of 1-12 hours, preferably 2-6 hours; in step S2, the conditions for the impregnation may include: an impregnation temperature of 20-150°C, and an impregnation time of 1-6 hours; the conditions for the second drying may include: a temperature of 100-300°C, preferably 100-200°C; a time of 2-8 hours; the conditions for the activation treatment may include: a temperature of 250-650°C, preferably 300-500°C; a time of 1-12 hours, preferably 2-6 hours.

[0038] A third aspect of the present disclosure provides a method for hydrocracking a feedstock oil rich in bicyclic aromatics, comprising contacting the feedstock oil rich in bicyclic aromatics and hydrogen with the above-mentioned hydrogenation catalyst and performing a hydrocracking reaction.

[0039] The present disclosure is further illustrated by the following examples, but the present disclosure is not limited thereto. Unless otherwise specified, all reagents used in the examples are chemically pure reagents.

[0040] The adsorption molar ratio test method disclosed herein involves accurately measuring a benzene and butylbenzene solution (100 ml, room temperature), then adding a predetermined amount of molecular sieve material (5 g). Under an inert gas (N2) atmosphere, the mixture is sealed and stirred at 360°C for 10 hours at 1 atmosphere. The mixture is then filtered, the filtrate is brought to a constant volume, cooled to room temperature, and the solution volume is measured again using a graduated cylinder. Pore volume is determined by BET, and acid content by NH3-TPD.

[0041] Example 1

[0042] 130.2 g of pseudo-boehmite (Catalyst Changling Branch) with a dry basis of 70% and 115.2 g of PKU-16 molecular sieve with a dry basis of 82% were weighed and extruded into three-lobed strips with a circumscribed circle diameter of 1.6 mm on an extruder. The strips were dried at 120°C for 3 hours and calcined at 600°C for 4 hours to obtain catalyst carrier Z1.

[0043] 100 g of support Z1 was impregnated for 3 hours with 80 ml of a mixed solution of molybdenum trioxide, basic nickel carbonate, and phosphoric acid containing 187.5 g / L MoO₃, 37.5 g / L NiO, and 37.5 g / L P₂O₅, respectively. The catalyst was then dried at 120°C for 2 hours and calcined at 450°C for 3 hours to obtain Catalyst C1. The composition of the catalyst after calcination is shown in Table 2.

[0044] Example 2

[0045] 130.2 g of pseudo-boehmite (Catalyst Changling Branch) with a dry basis of 70% and 114.6 g of SCM-15 molecular sieve (marked as A) with a dry basis of 82% were weighed and extruded into three-lobed strips with a circumscribed circle diameter of 1.6 mm on an extruder. The strips were dried at 120°C for 3 hours and calcined at 600°C for 4 hours to obtain the catalyst carrier Z2.

[0046] 100 g of support Z2 was impregnated for 3 hours with 80 ml of a mixed solution of molybdenum trioxide, basic nickel carbonate, and phosphoric acid containing 187.5 g / L MoO3, 37.5 g / L NiO, and 37.5 g / L P2O5, respectively. The catalyst was then dried at 120°C for 2 hours and calcined at 450°C for 3 hours to obtain Catalyst C2. The composition after calcination, based on the catalyst, is shown in Table 2.

[0047] Comparative Example 1

[0048] 130.2 g of pseudo-boehmite (Catalyst Changling Branch) with a dry basis of 70% and 114.6 g of Y molecular sieve with a dry basis of 82% were weighed and extruded into three-lobed strips with a circumscribed circle diameter of 1.6 mm on an extruder. The strips were dried at 120°C for 3 hours and calcined at 600°C for 4 hours to obtain the catalyst carrier Zd1.

[0049] 100 g of carrier Zd1 was impregnated for 3 hours with 80 ml of a mixed solution of molybdenum trioxide, basic nickel carbonate, and phosphoric acid containing 187.5 g / L MoO3, 37.5 g / L NiO, and 37.5 g / L P2O5, respectively. The catalyst was then dried at 120°C for 2 hours and calcined at 450°C for 3 hours to obtain Catalyst DC. The composition after calcination, based on the catalyst, is shown in Table 2.

[0050] Table 1

[0051]

[0052] Table 2

[0053]

[0054] Test Case

[0055] The tetralin reactivity performance of catalysts C1, C2, and DC provided by the present invention was evaluated on a micro-fixed bed using 99% pure tetralin (analytical grade) as the starting material. The catalyst loading was 1.0 g, and the reaction conditions were 330°C to 390°C and 4.0 MPa. For better comparison, the following two performance indicators were defined and presented. The results are listed in Table 3.

[0056] Conversion rate =

[0057] BTX yield is the mass fraction of benzene, toluene and xylene in the product, %

[0058] BTX selectivity = BTX yield / tetralin conversion rate × 100%

[0059] Table 3

[0060]

[0061] It can be seen from Table 3 that, compared with existing catalysts, the catalyst provided by the present disclosure can obtain higher selectivity and yield of the target product when used in the process of catalytic diesel hydrocracking to produce BTX.

[0062] The preferred embodiments of the present disclosure are described in detail above. However, the present disclosure is not limited to the specific details of the above embodiments. Within the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the scope of protection of the present disclosure.

[0063] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0064] In addition, the various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A hydrogenation catalyst for a feedstock oil rich in bicyclic aromatic hydrocarbons, characterized in that: The hydrogenation catalyst includes a carrier and an active metal component supported on the carrier; the active metal component includes a Group VIII metal element and a Group VIB metal element; the carrier is composed of an acidic component and a matrix, the acidic component is a molecular sieve with a BX value greater than 1; the molecular sieve is at least one selected from PKU-16 molecular sieve, SCM-15 molecular sieve, ITQ-4 molecular sieve, JU-64 molecular sieve, Beryllophosphate-H molecular sieve and UCSB-10GaZn molecular sieve; The BX value of a certain molecular sieve to be tested is defined as the molar ratio of the amount of benzene adsorbed by the molecular sieve to be tested to the amount of butylbenzene adsorbed by the molecular sieve to be tested.

2. The hydrogenation catalyst according to claim 1, wherein The BX value of the molecular sieve is 1-100 and is greater than 1.

3. The hydrogenation catalyst according to claim 2, wherein The BX value of the molecular sieve is 1-10 and greater than 1.

4. The hydrogenation catalyst according to any one of claims 1 to 3, wherein The pore volume of the molecular sieve is 0.4-0.8 cm 3 / g, acid density is 0.8-2.5 μmol / m 2 .

5. The hydrogenation catalyst according to claim 1, wherein Based on the total weight of the carrier, the content of the acidic component is 30-90% by weight; and the content of the matrix is ​​10-70% by weight.

6. The hydrogenation catalyst according to claim 5, wherein Based on the total weight of the carrier, the content of the acidic component is 45-80% by weight; and the content of the matrix is ​​20-55% by weight.

7. The hydrogenation catalyst according to claim 1, wherein Based on the total weight of the catalyst, the hydrogenation catalyst contains 1-10 wt% of Group VIII metal elements and 2-40 wt% of Group VIB metal elements in terms of oxides.

8. The hydrogenation catalyst according to claim 7, wherein Based on the total weight of the catalyst, the hydrogenation catalyst contains 1-6 wt% of Group VIII metal components and 5-25 wt% of Group VIB metal components in terms of oxides.

9. The hydrogenation catalyst according to claim 1, wherein The matrix is ​​selected from at least one of alumina, silica, and silica-alumina.

10. A method for preparing the hydrogenation catalyst according to claim 1, characterized in that: The method includes: S1. Mixing the matrix and the molecular sieve, kneading and extruding to obtain an extruded strip; performing a first drying and a first calcination on the extruded strip to obtain a carrier; S2. Impregnating the support with an aqueous solution containing a compound of a Group VIII metal and a compound of a Group VIB metal to obtain an impregnated support; and subjecting the impregnated support to a second drying and activation treatment.

11. The method according to claim 10, wherein: The weight ratio of the matrix to the molecular sieve is 3-7:7-3.

12. The method according to claim 10, wherein: In step S1, the conditions for the first drying treatment include: a drying temperature of 80-300°C; a drying time of 1-12 hours; the conditions for the first calcination include: a calcination temperature of 350-850°C; a calcination time of 1-12 hours; In step S2, the conditions for the impregnation include: an impregnation temperature of 20-150°C and an impregnation time of 1-6 hours; the conditions for the second drying include: a temperature of 100-300°C and a time of 2-8 hours; the conditions for the activation treatment include: a temperature of 250-650°C and a time of 1-12 hours.

13. The method according to claim 12, wherein: In step S1, the conditions for the first drying treatment include: a drying temperature of 100-200°C; a drying time of 2-8 hours; the conditions for the first calcination include: a calcination temperature of 450-650°C; a calcination time of 2-6 hours; The conditions for the second drying include: a temperature of 100-200° C.; the conditions for the activation treatment include: a temperature of 300-500° C.; and a time of 2-6 hours.

14. A method for hydrocracking a feedstock oil rich in bicyclic aromatic hydrocarbons, characterized in that: The method comprises: contacting a feedstock oil rich in bicyclic aromatic hydrocarbons and hydrogen with the hydrogenation catalyst according to any one of claims 1 to 9 and performing a hydrocracking reaction.

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