Metal-modified mordenite molecular sieve catalyst, its preparation method and regeneration method and application

Abstract

This invention provides a metal-modified mordenite molecular sieve catalyst, its preparation method, regeneration method, and applications, relating to the field of molecular sieve catalysts. The preparation method of the metal-modified mordenite molecular sieve catalyst includes the following steps: Step 1: Obtaining a mixture comprising a Ni-containing precursor, a Ce-containing precursor, and water; Step 2: Mixing the mixture obtained in Step 1 with mordenite molecular sieve and performing an impregnation treatment; Step 3: Calcination; Step 4: Conducting a reduction reaction in a reducing atmosphere at a temperature of 500-700℃ to obtain the metal-modified mordenite molecular sieve catalyst. The catalyst preparation method provided by this invention combines impregnation, calcination, and high-temperature reduction, utilizing Ce oxide and Ni to modify the mordenite molecular sieve, significantly improving the alkylation activity of the obtained catalyst.

Description

Technical Field

[0001] This invention relates to the field of molecular sieve catalysts, specifically to a metal-modified mordenite molecular sieve catalyst, its preparation method, regeneration method, and applications. Background Technology

[0002] Alkyl naphthalenes possess excellent thermal oxidation stability, hydrolytic stability, good additive solubility, and demulsification properties, making them widely used in hydraulic oils, gear oils, heat transfer oils, transformer oils, compressor oils, and liquid crystal displays. Isopropyl naphthalene series products can be used as heat transfer oils. Isopropyl naphthalene series heat transfer oils have advantages such as being odorless, non-corrosive to metals, having good thermal stability, excellent low-temperature performance, and being recyclable. The isopropyl naphthalene series mainly includes monoisopropyl naphthalene, diisopropyl naphthalene, and triisopropyl naphthalene. Diisopropyl naphthalene (DIPN) is an important fine chemical raw material for synthesizing naphthalene-containing polymers, and it is also a high-performance high-temperature synthetic heat transfer oil and electrical insulating oil. In particular, 2,6-diisopropyl naphthalene is a major raw material for synthesizing polyethylene naphthalate (PEN). The latter is a novel high-performance polyester material with wide applications in instrumentation, fibers, insulation materials, aerospace, and nuclear energy materials. Therefore, the synthesis of diisopropyl naphthalene is crucial.

[0003] The alkylation of naphthalene and propylene to prepare diisopropylnaphthalene theoretically yields more than ten mono- and poly-substituted products, and propylene itself undergoes polymerization, generating byproducts. This process requires sophisticated separation units. In contrast, the disproportionation reaction of monoisopropylnaphthalene to prepare diisopropylnaphthalene offers a shorter process route, simpler equipment, lower investment, and fewer reactants and byproducts.

[0004] Japanese Patent JP1988230646A describes the use of octahedral zeolite molecular sieves as a catalyst in the presence of saturated alicyclic hydrocarbons (preferably decahydronaphthalene, dicyclohexane, etc., used in amounts of 0.2-10% wt% of diisopropylnaphthalene) to carry out the disproportionation reaction of monoisopropylnaphthalene, thereby obtaining a high-yield compound and significantly improving the catalytic activity of the catalyst. This is achieved at temperatures of 160–300 °C and reaction pressures ≥0.5 kg / cm². 2Under optimal conditions, the highest conversion rate of 2-isopropylnaphthalene reached 100%, and the selectivity of the target product, 2,6-diisopropylnaphthalene, was 23.1%. Liu Yuanlin et al. studied the effect of MP-01 catalysts modified with different Fe2O3 contents prepared by the equal-volume impregnation method on the shape-selective disproportionation reaction of 2-isopropylnaphthalene. Using MP-01 catalysts modified with 2% Fe2O3 by mass, the conversion rate of 2-isopropylnaphthalene was 41.2%, the selectivity of diisopropylnaphthalene was 33.5%, and the selectivity of the target product, 2,6-diisopropylnaphthalene, was 41.2%. Yang et al. developed a simple and green experimental method to directly synthesize SFE-type zeolites doped with B, Al, Ti, V, or Fe using 4-dimethylaminopyridine as an organic structure directing agent. Among them, the aluminum-containing SFE zeolite showed better catalytic performance in the isopropylnaphthalene disproportionation reaction, with a 2-isopropylnaphthalene conversion rate of 26.8% and a selectivity of 37.9% for the target product, 2,6-diisopropylnaphthalene.

[0005] Currently, most synthetic methods for preparing diisopropylnaphthalene via disproportionation reactions employ zeolite molecular sieve catalysts. Molecular sieve catalysts not only exhibit high activity but also align with the principles of green and environmentally friendly development; however, reported studies generally suffer from low catalyst activity and low diisopropylnaphthalene yields. Furthermore, molecular sieve catalysts are prone to carbon deposition during disproportionation, leading to catalyst deactivation and requiring regeneration for recycling. Summary of the Invention

[0006] Based on the above analysis, the present invention aims to provide a metal-modified mordenite molecular sieve catalyst, its preparation method, regeneration method, and application, in order to solve at least one of the following existing technical problems: improving the conversion rate of monoisopropylnaphthalene and improving the selectivity of diisopropylnaphthalene.

[0007] The objective of this invention is mainly achieved through the following technical solutions:

[0008] In a first aspect, the present invention provides a method for preparing a metal-modified mordenite molecular sieve catalyst, comprising the following steps:

[0009] Step 1: Obtain a mixture comprising a Ni-containing precursor, a Ce-containing precursor, and water;

[0010] Step 2: Mix the mixture obtained in Step 1 with the mordenite molecular sieve and perform an impregnation treatment;

[0011] Step 3: Roasting;

[0012] Step 4: Carry out the reduction reaction in a reducing atmosphere at a temperature of 500-700℃ to obtain the metal-modified mordenite molecular sieve catalyst.

[0013] Preferably, in step 1, a dispersant is also added to the mixture.

[0014] Preferably, the dispersant includes at least one of ethylenediamine and urea.

[0015] Preferably, the molar ratio of the amount of the dispersant to the total amount of the Ni-containing precursor (calculated as Ni) and the Ce-containing precursor (calculated as Ce) is 0.5-1.

[0016] Preferably, in step 3, the roasting temperature is 500-600℃.

[0017] Preferably, in step 4, the reducing atmosphere includes hydrogen and argon. Preferably, the mass percentage of hydrogen in the reducing atmosphere is 1%-10%. More preferably, the flow rate of the reducing atmosphere is 5-15 mL / h.

[0018] Preferably, the total amount of Ni-containing precursors (calculated as Ni) and Ce-containing precursors (calculated as Ce) to the mass ratio of mordenite molecular sieve is (2-20):(80-98), more preferably (5-15):(85-95), and even more preferably (10-15):(85-90).

[0019] Preferably, the mass ratio of the Ni-containing precursor (calculated as Ni) to the mordenite molecular sieve is (1-10):(90-99), more preferably (5-10):(90-95).

[0020] Preferably, the mass ratio of the Ce-containing precursor (calculated as Ce) to the mordenite molecular sieve is (1-10):(90-99), more preferably (5-10):(90-95).

[0021] Preferably, in step 1, the Ni-containing precursor includes at least one of Ni nitrate, acetate, halide, sulfate, and acetate.

[0022] Preferably, in step 1, the Ce-containing precursor includes at least one of Ce nitrate, acetate, halide, sulfate, and acetate.

[0023] Preferably, in step 2, the mordenite molecular sieve is a hydrogen-type mordenite molecular sieve, and preferably, the silica-alumina ratio of the mordenite molecular sieve is 10-30.

[0024] Secondly, the present invention provides a metal-modified mordenite molecular sieve catalyst prepared by the preparation method described above.

[0025] Preferably, the total amount of Ni and Ce accounts for 2wt%-20wt% of the total weight of the catalyst, more preferably 5wt%-15wt%, and more preferably 10wt%-15wt%.

[0026] Preferably, the Ni content accounts for 1 wt% to 10 wt% of the total weight of the catalyst, more preferably 5 wt% to 10 wt%.

[0027] Preferably, the Ce content accounts for 1 wt% to 10 wt% of the total weight of the catalyst, more preferably 5 wt% to 10 wt%.

[0028] Thirdly, the present invention provides a method for regenerating a catalyst, comprising subjecting a deactivated catalyst to sequential polar solvent reflux treatment, nonpolar solvent ultrasonic treatment, and calcination treatment; wherein the deactivated catalyst is the metal-modified mordenite molecular sieve catalyst provided in the second aspect of the present invention.

[0029] Preferably, the polar solvent is selected from at least one of petroleum ether, ethanol, and ethyl acetate.

[0030] Preferably, the nonpolar solvent is selected from at least one of carbon tetrachloride, cyclohexane, and dichloroethane.

[0031] Preferably, the reflux treatment conditions include: a reflux temperature of 60℃ to 120℃ and a reflux time of 2h to 5h.

[0032] Preferably, the mass ratio of the polar solvent to the deactivated catalyst is (1-10):1.

[0033] Preferably, the reflux treatment includes centrifugation and a first drying step; preferably, the centrifugation conditions include: a rotation speed of 7000 rpm to 10000 rpm and a centrifugation time of 5 min to 20 min; the first drying conditions include: a first drying temperature of 80℃ to 120℃ and a first drying time of 10 h to 12 h.

[0034] Preferably, the conditions for the ultrasonic treatment include: an ultrasonic temperature of 25℃ to 120℃ and an ultrasonic power density of 0.1 W / cm². 2 ~15W / cm 2 The ultrasound time is 1 hour to 10 hours.

[0035] Preferably, the mass ratio of the nonpolar solvent to the deactivated catalyst is (1-10):1.

[0036] Preferably, the ultrasonic treatment includes a second drying step; preferably, the conditions for the second drying include: a second drying temperature of 80℃~120℃ and a second drying time of 10h~12h.

[0037] Preferably, the calcination conditions include: a calcination temperature of 500℃~650℃ and a calcination time of 3h~5h.

[0038] Fourthly, the present invention provides the application of the metal-modified mordenite molecular sieve catalyst or the catalyst regenerated by the regeneration method described above in the preparation method of diisopropylnaphthalene.

[0039] Fifthly, the present invention provides a method for preparing diisopropylnaphthalene, comprising the steps of: reacting monoisopropylnaphthalene in the presence of the metal-modified mordenite molecular sieve catalyst or the catalyst obtained by the regeneration method to obtain diisopropylnaphthalene.

[0040] Preferably, in the preparation method of diisopropylnaphthalene, the reaction temperature is 150-400℃, the reaction pressure is 1.0-3.5MPa, the reaction space velocity is 1000-12000mL / h / g, and the amount of the metal-modified mordenite molecular sieve catalyst or the catalyst obtained by the regeneration method is 0.5-10wt% of the mass of monoisopropylnaphthalene.

[0041] Beneficial effects:

[0042] The present invention provides a method for preparing a metal-modified mordenite molecular sieve catalyst, which combines impregnation, calcination and high-temperature reduction. The method utilizes Ce oxides, such as CeO2 and Ni, to modify the mordenite molecular sieve. There are a large number of coupling interfaces between Ce oxides and Ni, resulting in rich electronic interaction effects. This significantly enhances the synergistic effect between the metal sites and the acidic sites of the molecular sieve, and greatly improves the alkylation activity of the obtained catalyst. The catalyst exhibits high activity and selectivity when applied to the disproportionation of monoisopropylnaphthalene to produce diisopropylnaphthalene.

[0043] The regeneration method for deactivated catalysts provided by this invention is simple to operate, highly repeatable, and inexpensive to regenerate. First, a polar solvent reflux treatment dissolves carbon deposits on the outer surface and in the pores of the molecular sieve, simultaneously opening the internal pores. Then, a non-polar solvent ultrasonic treatment removes the carbon deposits on the surface of the internal pores. Finally, calcination burns off the solvent and other impurities. After these three steps, the deactivated catalyst can regain its active sites, restoring it to the level of a fresh catalyst, and can be reused in the disproportionation reaction to produce diisopropylnaphthalene, significantly extending the catalyst's lifespan and reducing the cost of catalyst preparation. Detailed Implementation

[0044] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0045] In this invention, Ni is the chemical element nickel; Ce is the chemical element cerium.

[0046] In a first aspect, the present invention provides a method for preparing a metal-modified mordenite molecular sieve catalyst, comprising the following steps:

[0047] Step 1: Obtain a mixture comprising a Ni-containing precursor, a Ce-containing precursor, and water;

[0048] Step 2: Mix the mixture obtained in Step 1 with the mordenite molecular sieve and perform an impregnation treatment;

[0049] Step 3: Filtration, washing, drying, and calcination.

[0050] Step 4: Carry out the reduction reaction in a reducing atmosphere at a temperature of 500-700℃ to obtain the metal-modified mordenite molecular sieve catalyst.

[0051] In this invention, the reduction temperature in step 4 is 500-700℃, which allows the nickel oxide to be reduced to nickel, while cerium remains in its oxide state. If the reduction temperature is too high, it will cause damage to the molecular sieve framework structure, potentially leading to its collapse; if the reduction temperature is too low, nickel will not be able to be reduced.

[0052] In a specific embodiment of the present invention, in step 1, a dispersant is also added to the mixture, and the dispersant is selected from at least one of ethylenediamine and urea.

[0053] In one specific embodiment of the present invention, the molar ratio of the dispersant to the total amount of Ni-containing precursor (calculated as Ni) and Ce-containing precursor (calculated as Ce) is 0.5-1, for example, 0.6, 0.7, 0.8, 0.9, etc. It should be noted that the use of the dispersant significantly improves the alkylation activity of the resulting catalyst by dispersing the metal distribution on the molecular sieve. When the molar ratio of the dispersant to the total amount of Ni and Ce is less than 0.5, the amount of dispersant is insufficient, resulting in poor dispersion and consequently, a decrease in the conversion rate of monoisopropylnaphthalene and the selectivity of diisopropylnaphthalene. When the molar ratio of the dispersant to the total amount of Ni and Ce is greater than 1, it will affect the physicochemical properties of the molecular sieve, such as acid sites and pore size distribution, leading to a decrease in the conversion rate of monoisopropylnaphthalene and the selectivity of diisopropylnaphthalene.

[0054] The present invention provides a method for preparing a metal-modified mordenite molecular sieve catalyst. This involves mixing a dispersant with a metal precursor and impregnating the molecular sieve to uniformly disperse nickel and cerium onto the inner and outer surfaces of the molecular sieve. Then, combining calcination and high-temperature reduction, the mordenite molecular sieve is modified using Ce oxides, such as CeO2, and Ni. The Ce oxides and Ni have numerous coupling interfaces, exhibiting rich electronic interaction effects, which significantly enhance the synergistic effect between the metal sites and the acidic sites of the molecular sieve. This substantially improves the alkylation activity of the resulting catalyst. The catalyst demonstrates high activity and selectivity when applied to the disproportionation of monoisopropylnaphthalene to produce diisopropylnaphthalene.

[0055] In one specific embodiment of the present invention, in step 1, the Ni precursor is at least one of Ni nitrate, acetate, halide, sulfate, and acetate.

[0056] In one specific embodiment of the present invention, step 1 contains at least one of nitrate, acetate, halide, sulfate, and acetate whose Ce precursor is Ce.

[0057] In a specific embodiment of the present invention, in step 2, the mordenite molecular sieve is a hydrogen-type mordenite molecular sieve (HM) with a silicon-to-aluminum ratio of 10-30.

[0058] In one specific embodiment of the present invention, in step 2, the immersion treatment temperature is 20-25°C and the time is 10-12 hours.

[0059] In one specific embodiment of the present invention, in step 3, the drying temperature is 80-120℃ and the drying time is 10-12h; the calcination temperature is 500-600℃ and the calcination time is 3-6h.

[0060] In one specific embodiment of the present invention, in step 4, the reduction time is 3-6 hours, the reducing atmosphere includes hydrogen and argon, wherein hydrogen accounts for 1%-10% of the gas mass, and the gas flow rate in the reducing atmosphere is 5-15 mL / h. It should be noted that in step 4, the control of the reduction temperature and the control of the gas flow rate in the reducing atmosphere ensures that the nickel oxide is fully reduced to elemental nickel, while cerium remains in its oxide state.

[0061] As a specific embodiment of the present invention, the total amount of Ni-containing precursor and Ce-containing precursor (calculated as Ni) to the mass ratio of mordenite molecular sieve is (2-20):(80-98), preferably (5-15):(85-95), and more preferably (10-15):(85-90).

[0062] As a specific embodiment of the present invention, the mass ratio of the Ni-containing precursor to the mordenite molecular sieve is (1-10):(90-99), preferably (5-10):(90-95).

[0063] As a specific embodiment of the present invention, the mass ratio of Ce-containing precursor to mordenite molecular sieve is (1-10):(90-99), preferably (5-10):(90-95).

[0064] It should be noted that zeolite catalysts supported by a single metal are prone to carbon deposition and deactivation due to their strong acidity, and the metal is also prone to sintering, which leads to catalyst deactivation. The method for preparing the metal-modified mordenite molecular sieve catalyst provided by this invention employs an impregnation method combined with calcination and high-temperature reduction. This results in a catalyst where Ni exists as a metallic element and Ce exists as an oxide. Numerous coupling interfaces exist between Ni and Ce oxides, exhibiting rich electronic interaction effects. This not only helps to improve electron movement but also plays a crucial role in stabilizing the metal composition. This strong interaction between the metal and oxides allows the Ce oxides to effectively inhibit the aggregation of Ni metal particles and improve metal dispersion, thereby significantly enhancing the synergistic effect between the metal sites and the acidic sites of the molecular sieve. This, in turn, greatly improves the catalyst activity and the selectivity and stability of diisopropylnaphthalene.

[0065] Secondly, the present invention provides a metal-modified mordenite molecular sieve catalyst prepared by the above preparation method.

[0066] As a specific embodiment of the present invention, the total amount of Ni and Ce, based on the total weight of the catalyst, accounts for 2wt%-20wt% of the catalyst weight, such as 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 11wt%, 12wt%, 13wt%, 14wt%, 15wt%, 16wt%, 17wt%, 18wt%, 19wt%, etc., preferably 5wt%-15wt%, more preferably 10wt%-15wt%; the mordenite molecular sieve catalyst accounts for 80wt%-98wt% of the catalyst weight, preferably 85wt%-95wt%, more preferably 85wt%-90wt%.

[0067] As a specific embodiment of the present invention, the Ni content accounts for 1wt%-10wt% of the total weight of the catalyst, for example, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, etc., preferably 5wt%-10wt%.

[0068] As a specific embodiment of the present invention, the Ce content accounts for 1wt%-10wt% of the total weight of the catalyst, for example 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, etc., preferably 5wt%-10wt%.

[0069] Thirdly, the present invention provides a method for regenerating a catalyst, comprising subjecting a deactivated catalyst to sequential polar solvent reflux treatment, nonpolar solvent ultrasonic treatment, and calcination treatment; wherein the deactivated catalyst is the metal-modified mordenite molecular sieve catalyst provided in the second aspect of the present invention.

[0070] In one specific embodiment of the present invention, the polar solvent is selected from at least one of petroleum ether, ethanol, and ethyl acetate.

[0071] As a specific embodiment of the present invention, the nonpolar solvent is selected from at least one of carbon tetrachloride, cyclohexane, and dichloroethane.

[0072] In this invention, the concentrations of the polar and non-polar solvents are not particularly limited. For example, the concentrations of the polar and non-polar solvents in this invention can be 10wt% to 100wt%, and the polar and non-polar solvents in this invention can be diluted with conventional solvents in the art.

[0073] As a specific embodiment of the present invention, the conditions for the reflux treatment include: reflux temperature of 60℃~120℃ and reflux time of 2h~5h.

[0074] In one specific embodiment of the present invention, the mass ratio of the polar solvent to the deactivated catalyst is (1-10):1.

[0075] As a specific embodiment of the present invention, the reflux treatment includes centrifugation and a first drying step; preferably, the centrifugation conditions include: a rotation speed of 7000 rpm to 10000 rpm and a centrifugation time of 5 min to 20 min; the first drying conditions include: a first drying temperature of 80℃ to 120℃ and a first drying time of 10 h to 12 h.

[0076] In this invention, polar solvents are easily volatilized upon heating. During the reflux process, the volatilization of polar solvents can be reduced or eliminated. At the same time, carbon deposits on the outer surface and pores of the molecular sieve can be dissolved and removed. However, since the reflux treatment is relatively mild, carbon deposits on the inner surface of the pores may remain and cannot be completely dissolved and removed. After the reflux treatment, the pores of the molecular sieve are reopened, which is beneficial for subsequent ultrasonic treatment and calcination.

[0077] In one specific embodiment of the present invention, the conditions for ultrasonic treatment include: an ultrasonic temperature of 25℃ to 120℃ and an ultrasonic power density of 0.1 W / cm². 2 ~15W / cm 2 The ultrasound time is 1 hour to 10 hours.

[0078] In one specific embodiment of the present invention, the mass ratio of the nonpolar solvent to the deactivated catalyst is (1-10):1.

[0079] As a specific embodiment of the present invention, the ultrasonic treatment includes a second drying step; preferably, the conditions for the second drying include: a second drying temperature of 80℃~120℃ and a second drying time of 10h~12h.

[0080] During the ultrasonic process described in this invention, a non-polar solvent with strong solubility enters the inner surface of the molecular sieve pores through high-speed oscillation to remove carbon deposits.

[0081] As a specific embodiment of the present invention, the calcination conditions include: a calcination temperature of 500℃~650℃ and a calcination time of 3h~5h.

[0082] The calcination process described in this invention can remove the solvent remaining in the molecular sieve and burn off impurities that cannot be dissolved in the solvent.

[0083] Fourthly, the present invention provides the application of the above-mentioned metal-modified mordenite molecular sieve catalyst or the catalyst regenerated by the above-mentioned regeneration method in the preparation method of diisopropylnaphthalene.

[0084] Fifthly, the present invention provides a method for preparing diisopropylnaphthalene, which involves producing diisopropylnaphthalene by disproportionation reaction of monoisopropylnaphthalene under the action of a modified catalyst or a catalyst obtained by regeneration method.

[0085] As a specific embodiment of the present invention, the preparation method of diisopropylnaphthalene includes the following steps: the raw material includes monoisopropylnaphthalene, and under the condition of the above-mentioned metal modified molecular sieve catalyst or the catalyst obtained by the above-mentioned regeneration method, pressurized gas is introduced and heated to carry out the reaction to obtain diisopropylnaphthalene.

[0086] It should be noted that the metal-modified molecular sieve catalysts provided by this invention, namely Ce oxide and Ni-modified mordenite molecular sieve catalysts, exhibit high activity in alkylation, especially in the disproportionation of monoisopropylnaphthalene to produce diisopropylnaphthalene, showing high activity and selectivity for diisopropylnaphthalene.

[0087] In one specific embodiment of the present invention, the diisopropylnaphthalene preparation method is carried out in a reactor, which includes at least one of a fixed-bed reactor, a fluidized-bed reactor, and a batch reactor.

[0088] In a specific embodiment of the present invention, the reaction temperature in the method for preparing diisopropylnaphthalene is 150-400℃, preferably 150-320℃, more preferably 150-300℃, the reaction pressure is 1.0-3.5MPa, the reaction space velocity is 1000-12000mL / h / g, and the reaction stirring speed is 500-1000r / min.

[0089] As a specific embodiment of the present invention, in the method for preparing diisopropylnaphthalene, the amount of catalyst used is 0.5-10 wt% of the mass of monoisopropylnaphthalene.

[0090] In one specific embodiment of the present invention, the catalyst particle size in the method for preparing diisopropylnaphthalene is 40-60 mesh.

[0091] In one specific embodiment of the present invention, in the method for preparing diisopropylnaphthalene, monoisopropylnaphthalene includes at least one of 1-isopropylnaphthalene and 2-isopropylnaphthalene.

[0092] It should be noted that the metal-modified mordenite molecular sieve catalyst, its preparation method, regeneration method, and application provided by this invention have the following advantages:

[0093] (1) The catalyst provided by the present invention has a simple preparation method, easy-to-control conditions, and high reproducibility.

[0094] (2) The catalyst provided by the present invention does not contain precious metals, which can reduce the cost of catalyst preparation for the production of diisopropylnaphthalene;

[0095] (3) The catalyst provided by this invention does not contain any components that pollute the environment and is an environmentally friendly catalyst;

[0096] (4) The catalyst provided by the present invention has higher catalytic activity and diisopropylnaphthalene selectivity in the production of diisopropylnaphthalene compared with the unmodified catalyst;

[0097] (5) The catalyst provided by the present invention does not use organic solvents such as cyclohexane in the production of diisopropylnaphthalene, which simplifies the separation process and reduces costs.

[0098] (6) The regeneration method for deactivated catalysts provided by the present invention is simple to operate, highly repeatable, and inexpensive to regenerate.

[0099] (7) The present invention first dissolves the carbon deposits on the outer surface and in the pores of the molecular sieve by reflux treatment with a polar solvent, and opens up the pores inside the molecular sieve. Then, the carbon deposits on the surface of the pores inside the molecular sieve can be removed by ultrasonic treatment with a non-polar solvent. Finally, the solvent and other impurities are burned off by calcination. After the above three steps, the deactivated catalyst can continue to expose active sites and be restored to the level of a fresh catalyst. It can be used again in the disproportionation reaction to produce diisopropylnaphthalene, which greatly extends the life of the catalyst and reduces the cost of catalyst preparation.

[0100] The following detailed description of preferred embodiments of the present invention illustrates the principles of the invention and is not intended to limit the scope of the invention.

[0101] Ethyl acetate was purchased from Shanghai Lingfeng Chemical Reagent Co., Ltd., with a purity of ≥99.5%.

[0102] Cyclohexane was purchased from Shanghai Lingfeng Chemical Reagent Co., Ltd., with a purity of ≥99.7%.

[0103] Ethanol was purchased from Jiangsu Yongfeng Chemical Reagent Co., Ltd., with a purity of ≥95%;

[0104] Carbon tetrachloride was purchased from Shanghai Maclean Biochemical Technology Co., Ltd., with a purity of ≥98%.

[0105] Petroleum ether was purchased from Shanghai Lingfeng Chemical Reagent Co., Ltd., with a boiling range of 60℃~90℃;

[0106] Dichloroethane was purchased from Jiangsu Qiangsheng Functional Chemical Co., Ltd., with a purity of ≥99.0%.

[0107] 2-Isopropylnaphthalene was purchased from Chemical Book, with a purity of 98%.

[0108] In the experiments conducted in the embodiments and comparative examples of this invention, the deactivated modified zeolite molecular sieve catalyst selected was the 5Ni-10Ce / HM catalyst prepared in Example 3 of this invention.

[0109] In the experimental examples of this invention, the performance of the regenerated catalyst was evaluated using a batch reactor method, and the products were analyzed using gas chromatography.

[0110] Unless otherwise specified, the raw materials and hydrogen-type mordenite molecular sieves used in the embodiments of this application were all obtained through commercial channels, with the hydrogen-type mordenite molecular sieves purchased from the Nankai University Catalyst Factory.

[0111] The formula for calculating the conversion rate (X) of monoisopropylnaphthalene is: X = (n0 - n1) / n0

[0112] Where: n0: the amount of monoisopropylnaphthalene added before the reaction.

[0113] n1: Amount of monoisopropylnaphthalene after the reaction

[0114] The formula for calculating the selectivity (S) of diisopropylnaphthalene is: S = m2 / (m + m2 + m3 + m4)

[0115] Where: m: the amount of naphthalene produced

[0116] m2: The amount of all diisopropylnaphthalene produced

[0117] m3: The amount of all triisopropylnaphthalene produced

[0118] m4: The amount of all tetraisopropylnaphthalene produced

[0119] Product qualitative analysis: To determine the peak assignments, the chromatographic retention times of each substance were determined using a pure substance injection method. Naphthalene, 2-isopropylnaphthalene, and 2,6-diisopropylnaphthalene were used to determine the retention times of the pure substances. Furthermore, the product composition of the monoisopropylnaphthalene disproportionation reaction was investigated using gas chromatography / mass spectrometry (GC / MS), combined with computer mass spectrometry library searching and manual spectral analysis.

[0120] Quantitative Analysis: Literature indicates that all isopropylnaphthalened derivatives of naphthalene possess the same response factor. Therefore, pure naphthalene, 2-isopropylnaphthalene, and 2,6-diisopropylnaphthalene were used to determine the GC response factor. Peak area correction and normalization were employed for quantitative determination of various samples.

[0121] Example 1

[0122] (1) Catalyst preparation method

[0123] Step 1: Weigh 0.25g Ni(NO3)2·6H2O, 0.15g Ce(NO3)3·6H2O and 0.06g ethylenediamine (the molar ratio of ethylenediamine to the total amount of Ni and Ce is 0.8) and dissolve them in 20mL of deionized water. Stir the precursor solution magnetically at room temperature for 10min at a speed of 500r / min to form a mixed solution.

[0124] Step 2: Weigh 4.90g of hydrogen-type mordenite molecular sieve (HM) (silicon-to-aluminum ratio of 15) and add it to the mixed solution. Stir at room temperature for 10 hours at a speed of 500r / min.

[0125] Step 3: Remove the product at room temperature, filter and wash with water, and dry at 100℃ for 12 hours; calcinate at 550℃ for 5 hours.

[0126] Step 4: After cooling to room temperature, remove the catalyst and transfer it to a small tube furnace. The temperature is increased to 600℃ at a rate of 2℃ / min. Then, 5% H2 / Ar is introduced at a flow rate of 10mL / h and calcined for 5h to obtain a modified mordenite molecular sieve catalyst of 1wt% Ni and 1wt% Ce (based on the total weight of the catalyst), denoted as 1Ni-1Ce / HM.

[0127] (2) Application of catalysts

[0128] The prepared 1Ni-1Ce / HM catalyst was ground, compressed, and shaped to 40-60 mesh. 3g of the shaped catalyst was added to a 300mL reactor, followed by 50g of 2-isopropylnaphthalene for the preparation of diisopropylnaphthalene. Nitrogen gas at 2.5MPa was introduced and then released to purge air. The temperature was programmed to rise to 250℃ at a rate of 10℃ / min. Timing was started at 250℃, and the reaction was carried out for 7 hours. Gas chromatography analysis was then performed on a sample. The conversion rate of 2-isopropylnaphthalene was 50.2%, and the selectivity for diisopropylnaphthalene was 40.5%.

[0129] Example 2

[0130] (1) Catalyst preparation method

[0131] Step 1: Weigh 1.24g Ni(NO3)2·6H2O, 0.77g Ce(NO3)3·6H2O and 0.29g ethylenediamine (the molar ratio of ethylenediamine to the total amount of Ni and Ce is 0.8) and dissolve them in 20mL of deionized water. Stir the precursor solution magnetically at room temperature for 10min at a speed of 500r / min to form a mixed solution.

[0132] Step 2: Weigh 4.50g of hydrogen-type mordenite molecular sieve (HM) (silicon-to-aluminum ratio of 15) and add it to the mixed solution. Stir at room temperature for 10 hours at a speed of 500r / min.

[0133] Step 3: Remove the product at room temperature, filter and wash with water, and dry at 100℃ for 12 hours; calcinate at 550℃ for 5 hours.

[0134] Step 4: After cooling to room temperature, remove the catalyst and transfer it to a small tube furnace. The temperature is increased to 600℃ at a rate of 2℃ / min. Then, 5% H2 / Ar is introduced at a flow rate of 10mL / h and calcined for 5h to obtain a modified mordenite molecular sieve catalyst of 5wt% Ni and 5wt% Ce (based on the total weight of the catalyst), denoted as 5Ni-5Ce / HM.

[0135] (2) Application of catalysts

[0136] The prepared 5Ni-5Ce / HM catalyst was ground, compressed, and shaped to 40-60 mesh. 3g of the shaped catalyst was added to a 300mL reactor, followed by 50g of 2-isopropylnaphthalene for the preparation of diisopropylnaphthalene. Nitrogen gas at 2.5MPa was introduced and then released to purge air. The temperature was programmed to rise to 250℃ at a rate of 10℃ / min. Timing was started at 250℃, and the reaction was carried out for 7 hours. Gas chromatography analysis was then performed on a sample. The conversion rate of 2-isopropylnaphthalene was 58.1%, and the selectivity for diisopropylnaphthalene was 45.8%.

[0137] Example 3

[0138] (1) Catalyst preparation method

[0139] Step 1: Weigh 1.24g Ni(NO3)2·6H2O, 1.55g Ce(NO3)3·6H2O and 0.38g ethylenediamine (the molar ratio of ethylenediamine to the total amount of Ni and Ce is 0.8) and dissolve them in 20mL of deionized water. Stir the precursor solution magnetically at room temperature for 10min at a speed of 500r / min to form a mixed solution.

[0140] Step 2: Weigh 4.25g of hydrogen-type mordenite molecular sieve (HM) (silicon-to-aluminum ratio of 15) and add it to the mixed solution. Stir at room temperature for 10 hours at a speed of 500 r / min.

[0141] Step 3: Remove the product at room temperature, filter and wash with water, and dry at 100℃ for 12 hours; calcinate at 550℃ for 5 hours.

[0142] Step 4: After cooling to room temperature, remove the catalyst and transfer it to a small tube furnace. The temperature is increased to 600℃ at a rate of 2℃ / min. Then, calcine it with 5% H2 / Ar at a flow rate of 10mL / h for 5h to obtain a modified mordenite molecular sieve catalyst of 5wt% Ni and 10wt% Ce (based on the total weight of the catalyst), denoted as 5Ni-10Ce / HM.

[0143] (2) Application of catalysts

[0144] The prepared 5Ni-10Ce / HM catalyst was ground, compressed, and shaped to 40-60 mesh. 3g of the shaped catalyst was added to a 300mL reactor, followed by the addition of 50g of 2-isopropylnaphthalene for the preparation of diisopropylnaphthalene. Nitrogen gas at 2.5MPa was introduced and then released to purge air. The temperature was programmed to rise to 250℃ at a rate of 10℃ / min. Timing was started at 250℃, and the reaction was carried out for 7 hours. Gas chromatography analysis was then performed on a sample. The conversion rate of 2-isopropylnaphthalene was 60.3%, and the selectivity for diisopropylnaphthalene was 49.6%.

[0145] Example 4

[0146] (1) Catalyst preparation method

[0147] Step 1: Weigh 2.48g Ni(NO3)2·6H2O, 1.55g Ce(NO3)3·6H2O and 0.58g ethylenediamine (the molar ratio of ethylenediamine to the total amount of Ni and Ce is 0.8) and dissolve them in 20mL of deionized water. Stir the precursor solution magnetically at room temperature for 10min at a speed of 500r / min to form a mixed solution.

[0148] Step 2: Weigh 4.00g of hydrogen-type mordenite molecular sieve (HM) (silicon-to-aluminum ratio of 15) and add it to the mixed solution. Stir at room temperature for 10 hours at a speed of 500r / min.

[0149] Step 3: Remove the product at room temperature, filter and wash with water, and dry at 100℃ for 12 hours; calcinate at 550℃ for 5 hours.

[0150] Step 4: After cooling to room temperature, remove the catalyst and transfer it to a small tube furnace. The temperature is increased to 600℃ at a rate of 2℃ / min. Then, 5% H2 / Ar is introduced at a flow rate of 10mL / h and calcined for 5h to obtain a modified mordenite molecular sieve catalyst with 10wt% Ni and 10wt% Ce (based on the total weight of the catalyst), denoted as 10Ni-10Ce / HM.

[0151] (2) Application of catalysts

[0152] The prepared 10Ni-10Ce / HM catalyst was ground, compressed, and shaped to 40-60 mesh. 3g of the shaped catalyst was added to a 300mL reactor, followed by 50g of 2-isopropylnaphthalene for the preparation of diisopropylnaphthalene. Nitrogen gas at 2.5MPa was introduced and then released to purge air. The temperature was programmed to rise to 250℃ at a rate of 10℃ / min. Timing was started at 250℃, and the reaction was carried out for 7 hours. Gas chromatography analysis was then performed on a sample. The conversion rate of 2-isopropylnaphthalene was 62.2%, and the selectivity for diisopropylnaphthalene was 44.5%.

[0153] Example 5

[0154] This embodiment is basically the same as Example 1, except that in the catalyst preparation method, a modified mordenite molecular sieve catalyst of 10wt% Ni and 5wt% Ce (based on the total weight of the catalyst) is prepared, denoted as 10Ni-5Ce / HM.

[0155] The conversion rate of 2-isopropylnaphthalene was 58.4%, and the selectivity of diisopropylnaphthalene was 47.7%.

[0156] Example 6

[0157] This embodiment is basically the same as Example 1, except that in the catalyst preparation method, the molar ratio of ethylenediamine to the total amount of Ni and Ce is 1.

[0158] The conversion rate of 2-isopropylnaphthalene was 51.7%, and the selectivity of diisopropylnaphthalene was 43.9%.

[0159] Example 7

[0160] This embodiment is basically the same as Embodiment 3, except that ethylenediamine is replaced with urea.

[0161] The conversion rate of 2-isopropylnaphthalene was 59.5%, and the selectivity of diisopropylnaphthalene was 49.1%.

[0162] Example 8

[0163] (1) Catalyst preparation method

[0164] Step 1: Weigh 1.24g Ni(NO3)2·6H2O and 1.55g Ce(NO3)3·6H2O of the precursor and dissolve them in 20mL of deionized water. Stir the precursor solution magnetically at room temperature for 10min at a speed of 500r / min to form a mixed solution.

[0165] Step 2: Weigh 4.25g of hydrogen-type mordenite molecular sieve (HM) (silicon-to-aluminum ratio of 15) and add it to the mixed solution. Stir at room temperature for 10 hours at a speed of 500 r / min.

[0166] Step 3: After cooling to room temperature, remove the catalyst and transfer it to a small tube furnace. The temperature is increased to 600℃ at a rate of 2℃ / min. Then, 5% H2 / Ar is introduced at a flow rate of 10mL / h and calcined for 5h to obtain a modified mordenite molecular sieve catalyst of 5wt% Ni and 10wt% Ce (based on the total weight of the catalyst), denoted as 5Ni-10Ce / HM.

[0167] (2) Application of catalysts

[0168] The prepared catalyst was ground, compressed, and shaped to 40-60 mesh. 3g of the shaped catalyst was added to a 300mL reactor, followed by 50g of 2-isopropylnaphthalene for the preparation of diisopropylnaphthalene. Nitrogen gas at 2.5MPa was introduced and then released to purge air. The temperature was programmed to rise to 250℃ at a rate of 10℃ / min. Timing was started at 250℃, and the reaction was carried out for 7 hours. Samples were then analyzed by gas chromatography. The conversion rate of 2-isopropylnaphthalene was 50.3%, and the selectivity for diisopropylnaphthalene was 40.6%.

[0169] Comparative Example 1

[0170] Weigh 5.00g of unmodified hydrogen-type mordenite molecular sieve (HM) (silicon-to-aluminum ratio of 15), grind, press into tablets and shape to 40-60 mesh.

[0171] 3g of the pre-formed catalyst was added to a 300mL reactor, followed by 50g of 2-isopropylnaphthalene for the preparation of diisopropylnaphthalene. Nitrogen gas at 2.5MPa was introduced and then released to purge air. The temperature was programmed to rise to 250℃ at a rate of 10℃ / min. Timing was started at 250℃, and the reaction was carried out for 7 hours. Samples were then analyzed by gas chromatography. The conversion rate of 2-isopropylnaphthalene was 28.1%, and the selectivity for diisopropylnaphthalene was 21.7%.

[0172] Comparative Example 2

[0173] (1) Catalyst preparation method

[0174] Step 1: Weigh 0.50g Ni(NO3)2·6H2O and 0.08g ethylenediamine (the molar ratio of ethylenediamine to Ni is 0.8) and dissolve them in 20mL of deionized water. Stir the precursor solution magnetically at room temperature for 10min at a speed of 500r / min to form a mixed solution.

[0175] Step 2: Weigh 4.80g of hydrogen-type mordenite molecular sieve (HM) (silicon-to-aluminum ratio of 15) and add it to the mixed solution. Stir at room temperature for 10 hours at a speed of 500r / min.

[0176] Step 3: Remove the product at room temperature, filter and wash with water, and dry at 100℃ for 12 hours; calcinate at 550℃ for 5 hours.

[0177] Step 4: After cooling to room temperature, remove the catalyst and transfer it to a small tube furnace. The temperature is increased to 600℃ at a rate of 2℃ / min. 5% H2 / Ar is introduced at a flow rate of 10mL / h and calcined for 5h to obtain 2wt% Ni (based on the total weight of the catalyst) modified mordenite molecular sieve catalyst, denoted as 2Ni / HM.

[0178] (2) Application of catalysts

[0179] The prepared catalyst was ground, compressed, and shaped to 40-60 mesh. 3g of the shaped catalyst was added to a 300mL reactor, followed by 50g of 2-isopropylnaphthalene for the preparation of diisopropylnaphthalene. Nitrogen gas at 2.5MPa was introduced and then released to purge air. The temperature was programmed to rise to 250℃ at a rate of 10℃ / min. Timing was started at 250℃, and the reaction was carried out for 7 hours. Gas chromatography analysis was then performed on a sample. The conversion rate of 2-isopropylnaphthalene was 43.5%, and the selectivity for diisopropylnaphthalene was 38.7%.

[0180] Comparative Example 3

[0181] (1) Catalyst preparation method

[0182] Step 1: Weigh 0.31g Ce(NO3)3·6H2O and 0.03g ethylenediamine (the molar ratio of ethylenediamine to total Ce is 0.8) and dissolve them in 20mL of deionized water. Stir the precursor solution magnetically at room temperature for 10min at a speed of 500r / min to form a mixed solution.

[0183] Step 2: Weigh 4.80g of hydrogen-type mordenite molecular sieve (HM) (silicon-to-aluminum ratio of 15) and add it to the mixed solution. Stir at room temperature for 10 hours at a speed of 500r / min.

[0184] Step 3: Remove the product at room temperature, filter and wash with water, and dry at 100℃ for 12 hours; calcinate at 550℃ for 5 hours.

[0185] Step 4: After cooling to room temperature, remove the catalyst and transfer it to a small tube furnace. The temperature is increased to 600℃ at a rate of 2℃ / min. Then, 5% H2 / Ar is introduced at a flow rate of 10mL / h and calcined for 5h to obtain 2wt% Ce (based on the total weight of the catalyst) modified mordenite molecular sieve catalyst, denoted as 2Ce / HM.

[0186] (2) Application of catalysts

[0187] The prepared catalyst was ground, compressed, and shaped to 40-60 mesh. 3g of the shaped catalyst was added to a 300mL reactor, followed by 50g of 2-isopropylnaphthalene for the preparation of diisopropylnaphthalene. Nitrogen gas at 2.5MPa was introduced and then released to purge air. The temperature was programmed to rise to 250℃ at a rate of 10℃ / min. Timing was started at 250℃, and the reaction was carried out for 7 hours. Gas chromatography analysis was then performed on a sample. The conversion rate of 2-isopropylnaphthalene was 42.0%, and the selectivity for diisopropylnaphthalene was 37.9%.

[0188] Comparative Example 4

[0189] (1) Catalyst preparation method

[0190] Step 1: Weigh 1.24g Ni(NO3)2·6H2O, 1.55g Ce(NO3)3·6H2O and 0.38g ethylenediamine (the molar ratio of ethylenediamine to the total amount of Ni and Ce is 0.8) and dissolve them in 20mL of deionized water. Stir the precursor solution magnetically at room temperature for 10min at a speed of 500r / min to form a mixed solution.

[0191] Step 2: Weigh 4.25g of hydrogen-type mordenite molecular sieve (HM) (silicon-to-aluminum ratio of 15) and add it to the mixed solution. Stir at room temperature for 10 hours at a speed of 500 r / min.

[0192] Step 3: Remove the product, filter and wash with water, dry at 100℃ for 12 hours; calcine at 550℃ for 5 hours. A modified mordenite molecular sieve catalyst of 5wt% Ni and 10wt% Ce (based on the total weight of the catalyst) is obtained, denoted as 5Ni-10Ce / HM.

[0193] (2) Application of catalysts

[0194] The prepared catalyst was ground, compressed, and shaped to 40-60 mesh. 3g of the shaped catalyst was added to a 300mL reactor, followed by 50g of 2-isopropylnaphthalene for the preparation of diisopropylnaphthalene. Nitrogen gas at 2.5MPa was introduced and then released to purge air. The temperature was programmed to rise to 250℃ at a rate of 10℃ / min. Timing was started at 250℃, and the reaction was carried out for 7 hours. Samples were then analyzed by gas chromatography. The conversion rate of 2-isopropylnaphthalene was 45.3%, and the selectivity for diisopropylnaphthalene was 41.6%.

[0195] Comparative Example 5

[0196] This comparative example is basically the same as Example 3, except that in the preparation method of the catalyst, the mordenite molecular sieve is replaced with USY-35.

[0197] The conversion rate of 2-isopropylnaphthalene was 10.3%, and the selectivity of diisopropylnaphthalene was 38.2%.

[0198] Comparative Example 6

[0199] This comparative example is basically the same as Example 1, except that Ce(NO3)3·6H2O is replaced with Mg(NO3)2·6H2O in the catalyst preparation method to prepare a 1wt% Ni and 1wt% Mg (based on the total weight of the catalyst) modified mordenite molecular sieve catalyst, denoted as 1Ni-1Mg / HM.

[0200] The conversion rate of 2-isopropylnaphthalene was 44.2%, and the selectivity of diisopropylnaphthalene was 38.7%.

[0201] Example 9

[0202] This embodiment illustrates the method for regenerating the catalyst described in this invention.

[0203] The specific steps are as follows:

[0204] The deactivated modified zeolite molecular sieve catalyst was added to ethyl acetate at a solid-liquid mass ratio of 1:5, heated to 80℃ and refluxed for 2 hours, then centrifuged at 8000 rpm for 10 minutes. The mixture was filtered to separate the solid and liquid phases, obtaining a filter residue. The residue was dried in an oven at 100℃ for 10 hours to obtain the S1 semi-finished product. The S1 semi-finished product was then added to cyclohexane at a solid-liquid mass ratio of 1:5 and treated with an ultrasonic machine at 100℃ and an ultrasonic power density of 2.0 W / cm³. 2 The processing time was 5 hours. The residue was then filtered and dried in a drying oven at 100°C for 10 hours to obtain the S2 semi-finished product. The dried S2 semi-finished product was then calcined in a muffle furnace at 550°C for 5 hours. After natural cooling for 12 hours, the regenerated molecular sieve catalyst was obtained, denoted as catalyst Z1.

[0205] Example 10

[0206] This embodiment illustrates the method for regenerating the catalyst described in this invention.

[0207] The specific steps are as follows:

[0208] The deactivated modified zeolite molecular sieve catalyst was added to ethanol at a solid-liquid mass ratio of 1:5, heated to 80℃ and refluxed for 2 hours, then centrifuged at 8000 rpm for 10 minutes. The mixture was filtered to separate the solid and liquid phases, obtaining a filter residue. The filter residue was dried in an oven at 100℃ for 10 hours to obtain the S1 semi-finished product. The S1 semi-finished product was then added to carbon tetrachloride at a solid-liquid mass ratio of 1:5 and treated using an ultrasonic machine at 100℃ and an ultrasonic power density of 2.0 W / cm³. 2 The processing time was 5 hours. The residue was then filtered and dried in a drying oven at 100°C for 10 hours to obtain the S2 semi-finished product. The dried S2 semi-finished product was then calcined in a muffle furnace at 550°C for 5 hours. After natural cooling for 12 hours, the regenerated molecular sieve catalyst was obtained, denoted as Z2 catalyst.

[0209] Example 11

[0210] This embodiment illustrates the method for regenerating the catalyst described in this invention.

[0211] The specific steps are as follows:

[0212] The deactivated modified zeolite molecular sieve catalyst was added to petroleum ether at a solid-liquid mass ratio of 1:5, heated to 60℃~90℃ and refluxed for 2 hours, then centrifuged at 8000 rpm for 10 minutes. The mixture was filtered to separate the solid and liquid phases, obtaining a filter residue. The filter residue was dried in an oven at 100℃ for 10 hours to obtain the S1 semi-finished product. The S1 semi-finished product was then added to dichloroethane at a solid-liquid mass ratio of 1:5 and treated ultrasonically at 100℃ and an ultrasonic power density of 2.0 W / cm³. 2 The processing time was 5 hours. The residue was then filtered and dried in a drying oven at 100°C for 10 hours to obtain the S2 semi-finished product. The dried S2 semi-finished product was then calcined in a muffle furnace at 550°C for 5 hours. After natural cooling for 12 hours, the regenerated molecular sieve catalyst was obtained, denoted as catalyst Z3.

[0213] Example 12

[0214] This embodiment illustrates the method for regenerating the catalyst described in this invention.

[0215] The specific steps are as follows:

[0216] The deactivated modified zeolite molecular sieve catalyst was added to ethyl acetate at a solid-liquid mass ratio of 1:5, heated to 80℃ and refluxed for 2 hours, then centrifuged at 8000 rpm for 10 minutes. The mixture was filtered to separate the solid and liquid phases, obtaining a filter residue. The residue was dried in an oven at 100℃ for 10 hours to obtain the S1 semi-finished product. The S1 semi-finished product was then added to dichloroethane at a solid-liquid mass ratio of 1:5 and treated with an ultrasonic machine at 100℃ and an ultrasonic power density of 2.0 W / cm³. 2 The processing time was 5 hours. The residue was then filtered and dried in a drying oven at 100°C for 10 hours to obtain the S2 semi-finished product. The dried S2 semi-finished product was then calcined in a muffle furnace at 550°C for 5 hours. After natural cooling for 12 hours, the regenerated molecular sieve catalyst was obtained, denoted as catalyst Z4.

[0217] Example 13

[0218] This embodiment illustrates the method for regenerating the catalyst described in this invention.

[0219] The specific steps are as follows:

[0220] The deactivated modified zeolite molecular sieve catalyst was added to a mixed solvent of ethyl acetate and ethanol (mass ratio 1:1) at a solid-liquid ratio of 1:5. The mixture was heated to 80°C and refluxed for 2 hours, followed by centrifugation at 8000 rpm for 10 minutes. The mixture was then filtered to separate the solid and liquid phases, yielding a filter residue. This residue was dried in an oven at 100°C for 10 hours to obtain the S1 semi-finished product. The S1 semi-finished product was then added to dichloroethane at a solid-liquid ratio of 1:5 and treated using an ultrasonic machine at 100°C and an ultrasonic power density of 2.0 W / cm³. 2 The processing time was 5 hours. The residue was then filtered and dried in a drying oven at 100°C for 10 hours to obtain the S2 semi-finished product. The dried S2 semi-finished product was then calcined in a muffle furnace at 550°C for 5 hours. After natural cooling for 12 hours, the regenerated molecular sieve catalyst was obtained, denoted as Z5 catalyst.

[0221] Example 14

[0222] This embodiment illustrates the method for regenerating the catalyst described in this invention.

[0223] The specific steps are as follows:

[0224] The deactivated modified zeolite molecular sieve catalyst was added to ethyl acetate at a solid-liquid mass ratio of 1:5, heated to 80℃ and refluxed for 2 hours, then centrifuged at 8000 rpm for 10 minutes. The mixture was filtered to separate the solid and liquid phases, obtaining a filter residue. The filter residue was dried in an oven at 100℃ for 10 hours to obtain the S1 semi-finished product. The S1 semi-finished product was then added to a mixed solvent of dichloroethane and cyclohexane (mass ratio of dichloroethane to cyclohexane 1:1) at a solid-liquid mass ratio of 1:5, and treated in an ultrasonic machine at a temperature of 100℃ and an ultrasonic power density of 2.0 W / cm³. 2 The processing time was 5 hours. The residue was then filtered and dried in a drying oven at 100°C for 10 hours to obtain the S2 semi-finished product. The dried S2 semi-finished product was then calcined in a muffle furnace at 550°C for 5 hours. After natural cooling for 12 hours, the regenerated molecular sieve catalyst was obtained, denoted as Z6 catalyst.

[0225] Comparative Example 7

[0226] This comparative example is used to illustrate the catalyst regeneration method described in this invention.

[0227] The specific steps are as follows:

[0228] The deactivated modified zeolite molecular sieve catalyst was added to ethyl acetate at a solid-liquid mass ratio of 1:5, allowed to stand at 25°C for 2 hours, and then centrifuged at 8000 rpm for 10 minutes. The mixture was filtered to separate the solid and liquid phases, obtaining a filter residue. The residue was dried in an oven at 100°C for 10 hours and then calcined in a muffle furnace at 550°C for 5 hours. After natural cooling for 12 hours, the regenerated molecular sieve catalyst was obtained, denoted as catalyst DZ1.

[0229] Comparative Example 8

[0230] This comparative example is used to illustrate the catalyst regeneration method described in this invention.

[0231] The specific steps are as follows:

[0232] The deactivated modified zeolite molecular sieve catalyst was added to ethyl acetate at a solid-liquid mass ratio of 1:5, heated to 80°C and refluxed for 2 hours, then centrifuged at 8000 rpm for 10 minutes. The mixture was filtered to separate the solid and liquid phases, obtaining a filter residue. The residue was dried in an oven at 100°C for 10 hours, then calcined in a muffle furnace at 550°C for 5 hours. After natural cooling for 12 hours, the regenerated molecular sieve catalyst was obtained, denoted as catalyst DZ2.

[0233] Comparative Example 9

[0234] This comparative example is used to illustrate the catalyst regeneration method described in this invention.

[0235] The specific steps are as follows:

[0236] The deactivated modified zeolite molecular sieve catalyst was added to cyclohexane at a solid-liquid mass ratio of 1:5, allowed to stand at 25°C for 2 hours, and then filtered to obtain filter residue. The filter residue was dried in a drying oven at 100°C for 10 hours and then calcined in a muffle furnace at 550°C for 5 hours. After natural cooling for 12 hours, the regenerated molecular sieve catalyst was obtained, denoted as catalyst DZ3.

[0237] Comparative Example 10

[0238] This embodiment illustrates the method for regenerating the catalyst described in this invention.

[0239] The specific steps are as follows:

[0240] The deactivated modified zeolite molecular sieve catalyst was added to cyclohexane at a solid-liquid mass ratio of 1:5 and then treated in an ultrasonic machine at a temperature of 100℃ and an ultrasonic power density of 2.0 W / cm³. 2 The processing time was 5 hours. The residue was then filtered and dried in a drying oven at 100°C for 10 hours, followed by calcination in a muffle furnace at 550°C for 5 hours. After natural cooling for 12 hours, the regenerated molecular sieve catalyst was obtained, denoted as catalyst DZ4.

[0241] Comparative Example 11

[0242] This comparative example is used to illustrate the catalyst regeneration method described in this invention.

[0243] The specific steps are as follows:

[0244] The deactivated modified zeolite molecular sieve catalyst was added to ethyl acetate at a solid-liquid mass ratio of 1:5, heated to 80℃ and refluxed for 2 hours, then centrifuged at 8000 rpm for 10 minutes. The mixture was filtered to separate the solid and liquid phases, obtaining a filter residue. The filter residue was dried in an oven at 100℃ for 10 hours to obtain the S1 semi-finished product. The S1 semi-finished product was then added to cyclohexane at a solid-liquid mass ratio of 1:5 and allowed to stand at 25℃ for 5 hours. The mixture was then filtered to obtain a filter residue, which was dried in a drying oven at 100℃ for 10 hours to obtain the S2 semi-finished product. The dried S2 semi-finished product was calcined in a muffle furnace at 550℃ for 5 hours. After natural cooling for 12 hours, the regenerated molecular sieve catalyst was obtained, denoted as catalyst DZ5.

[0245] Comparative Example 12

[0246] This comparative example is used to illustrate the catalyst regeneration method described in this invention.

[0247] The specific steps are as follows:

[0248] The deactivated modified zeolite molecular sieve catalyst was added to ethyl acetate at a solid-liquid mass ratio of 1:5, allowed to stand at 25°C for 5 hours, filtered, and the solid and liquid were separated to obtain filter residue. The filter residue was dried in an oven at 100°C for 10 hours to obtain the S1 semi-finished product. The S1 semi-finished product was added to dichloroethane at a solid-liquid mass ratio of 1:5 and treated in an ultrasonic machine at a temperature of 100°C and an ultrasonic power density of 2.0 W / cm³. 2 The processing time was 5 hours. The residue was then filtered and dried in a drying oven at 100°C for 10 hours to obtain the S2 semi-finished product. The dried S2 semi-finished product was then calcined in a muffle furnace at 550°C for 5 hours. After natural cooling for 12 hours, the regenerated molecular sieve catalyst was obtained, denoted as DZ6 catalyst.

[0249] Comparative Example 13

[0250] This comparative example is used to illustrate the catalyst regeneration method described in this invention.

[0251] The specific steps are as follows:

[0252] The S1 semi-finished product was added to cyclohexane at a solid-liquid mass ratio of 1:5, and then treated in an ultrasonic machine at a temperature of 100℃ and an ultrasonic power density of 2.0 W / cm³. 2The processing time was 5 hours. The residue was then filtered and dried in a drying oven at 100°C for 10 hours to obtain the S1 semi-finished product. The deactivated modified zeolite molecular sieve catalyst was added to ethyl acetate at a solid-liquid mass ratio of 1:5, heated to 80°C and refluxed for 2 hours, then centrifuged at 8000 rpm for 10 minutes. The residue was filtered to separate the solid and liquid phases. This residue was then dried in an oven at 100°C for 10 hours to obtain the S2 semi-finished product. The dried S2 semi-finished product was calcined in a muffle furnace at 550°C for 5 hours. After natural cooling for 12 hours, the regenerated molecular sieve catalyst was obtained, denoted as catalyst DZ7.

[0253] Comparative Example 14

[0254] This comparative example is used to illustrate the catalyst regeneration method described in this invention.

[0255] The specific steps are as follows:

[0256] The deactivated modified zeolite molecular sieve catalyst was added to ethyl acetate at a solid-liquid mass ratio of 1:5, heated to 80℃ and refluxed for 2 hours, then centrifuged at 8000 rpm for 10 minutes. The mixture was filtered to separate the solid and liquid phases, obtaining a filter residue. The residue was dried in an oven at 100℃ for 10 hours to obtain the S1 semi-finished product. The S1 semi-finished product was then added to cyclohexane at a solid-liquid mass ratio of 1:5 and treated with an ultrasonic machine at 100℃ and an ultrasonic power density of 2.0 W / cm³. 2 The processing time was 5 hours. Then, the filter residue was obtained by filtration and dried in a drying oven at 100°C for 10 hours to obtain the regenerated molecular sieve catalyst, denoted as DZ8 catalyst.

[0257] Comparative Example 15

[0258] This comparative example is used to illustrate the catalyst regeneration method described in this invention.

[0259] The specific steps are as follows:

[0260] The deactivated modified zeolite molecular sieve catalyst was first calcined in a muffle furnace at 550°C for 5 hours. After natural cooling for 12 hours, the calcined modified zeolite molecular sieve catalyst was obtained.

[0261] Then, the calcined modified zeolite molecular sieve catalyst was added to ethyl acetate at a solid-liquid mass ratio of 1:5, heated to 80℃~120℃ and refluxed for 2 hours, followed by centrifugation at 8000 rpm for 10 minutes. The mixture was filtered to separate the solid and liquid phases, obtaining a filter residue. The filter residue was dried in an oven at 100℃ for 10 hours to obtain the S1 semi-finished product. The S1 semi-finished product was then added to cyclohexane at a solid-liquid mass ratio of 1:5 and treated with an ultrasonic machine at 100℃ and an ultrasonic power density of 2.0 W / cm³. 2The processing time was 5 hours. Then, the filter residue was obtained by filtration and dried in a drying oven at 100°C for 10 hours to obtain the regenerated molecular sieve catalyst, denoted as DZ9 catalyst.

[0262] Application of regenerated catalysts

[0263] The catalysts regenerated using the methods described in Examples 9-14 and Comparative Examples 7-15 were ground, compressed, and shaped to 40-60 mesh. 3g of the shaped catalyst was added to a 300mL reactor, followed by 50g of 2-isopropylnaphthalene for the preparation of diisopropylnaphthalene. Nitrogen gas at 2.5MPa was introduced and then released to purge air. The temperature was programmed to rise to 250℃ at a rate of 10℃ / min. Timing was started at 250℃, and the reaction was carried out for 7 hours. Samples were then analyzed by gas chromatography. The experimental results are shown in Table 1.

[0264] Table 1. Catalytic performance of the regenerated catalyst described in this invention in the disproportionation of 2-isopropylnaphthalene to diisopropylnaphthalene.

[0265]

[0266]

[0267] As can be seen from the experimental data in Table 1, the 5Ni-10Ce / HM catalyst prepared in Example 3 of this invention, after deactivation, can be effectively regenerated by sequentially performing polar solvent reflux treatment, non-polar solvent ultrasonic treatment, and calcination treatment, and exhibits high catalytic performance after regeneration. Furthermore, compared with Comparative Examples 7-15, it can be found that the regeneration methods in Examples 9-14, which involve polar solvent reflux treatment and non-polar solvent ultrasonic treatment, can restore the activity of the deactivated catalyst to more than 95% of that of the fresh catalyst, essentially achieving the catalytic performance of the fresh catalyst.

[0268] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

Claims

1. A method for preparing a metal-modified mordenite molecular sieve catalyst, characterized in that, Includes the following steps: Step 1: Obtain a mixture comprising a Ni-containing precursor, a Ce-containing precursor, and water; Step 2: Mix the mixture obtained in Step 1 with the mordenite molecular sieve and perform an impregnation treatment; Step 3: Roasting; Step 4: Carry out the reduction reaction in a reducing atmosphere at a temperature of 500-700℃ to obtain the metal-modified mordenite molecular sieve catalyst.

2. The preparation method according to claim 1, characterized in that, In step 1, a dispersant is also added to the mixture. Preferably, the dispersant includes at least one of ethylenediamine and urea; Preferably, the molar ratio of the amount of the dispersant to the total amount of the Ni-containing precursor (calculated as Ni) and the Ce-containing precursor (calculated as Ce) is 0.5-1.

3. The preparation method according to claim 1 or 2, characterized in that, In step 3, the roasting temperature is 500-600℃; And / or, in step 4, the reducing atmosphere includes hydrogen and argon. Preferably, the mass percentage of hydrogen in the reducing atmosphere is 1%-10%. More preferably, the flow rate of the reducing atmosphere is 5-15 mL / h.

4. The preparation method according to any one of claims 1-3, characterized in that, The total amount of Ni-containing precursors and Ce-containing precursors (calculated as Ni) to the mass ratio of the mordenite molecular sieve is (2-20):(80-98), preferably (5-15):(85-95), and more preferably (10-15):(85-90).

5. The preparation method according to any one of claims 1-4, characterized in that, The mass ratio of the Ni-containing precursor (calculated as Ni) to the mordenite molecular sieve is (1-10):(90-99), preferably (5-10):(90-95); And / or, the mass ratio of the Ce-containing precursor to the mordenite molecular sieve, calculated as Ce, is (1-10):(90-99), preferably (5-10):(90-95).

6. The preparation method according to any one of claims 1-5, characterized in that, In step 1, the Ni-containing precursor includes at least one of Ni nitrate, acetate, halide, sulfate, and acetate. And / or, in step 1, the Ce-containing precursor includes at least one of Ce nitrate, acetate, halide, sulfate, and acetate; And / or, in step 2, the mordenite molecular sieve is a hydrogen-type mordenite molecular sieve, preferably, the silica-alumina ratio of the mordenite molecular sieve is 10-30.

7. A metal-modified mordenite molecular sieve catalyst prepared by the method according to any one of claims 1-6. Preferably, the total amount of Ni and Ce accounts for 2wt%-20wt% of the total weight of the catalyst, more preferably 5wt%-15wt%, and more preferably 10wt%-15wt% based on the total weight of the catalyst. Preferably, The Ni content, based on the total weight of the catalyst, is 1 wt% to 10 wt% of the catalyst weight, preferably 5 wt% to 10 wt%. And / or, based on the total weight of the catalyst, the Ce content accounts for 1 wt% to 10 wt% of the weight of the catalyst, preferably 5 wt% to 10 wt%.

8. A method for regenerating a catalyst, characterized in that, The process includes sequentially subjecting the deactivated catalyst to polar solvent reflux treatment, non-polar solvent ultrasonic treatment, and calcination treatment; the deactivated catalyst is the metal-modified mordenite molecular sieve catalyst as described in claim 7. Preferably, the polar solvent includes at least one of petroleum ether, ethanol, and ethyl acetate; And / or, the nonpolar solvent includes at least one of carbon tetrachloride, cyclohexane, and dichloroethane; More preferably, the reflux treatment conditions include: a reflux temperature of 60℃~120℃ and a reflux time of 2h~5h; And / or, the mass ratio of the polar solvent to the deactivated catalyst is (1-10):1; And / or, the reflux treatment includes centrifugation and a first drying step; preferably, the centrifugation conditions include: a rotation speed of 7000 rpm to 10000 rpm and a centrifugation time of 5 min to 20 min; the first drying conditions include: a first drying temperature of 80℃ to 120℃ and a first drying time of 10 h to 12 h; More preferably, the conditions for the ultrasonic treatment include: an ultrasonic temperature of 25℃~120℃ and an ultrasonic power density of 0.1W / cm². 2 ~15W / cm 2 The ultrasound time is 1 hour to 10 hours; And / or, the mass ratio of the nonpolar solvent to the deactivated catalyst is (1-10):1; And / or, the ultrasonic treatment includes a second drying step; preferably, the conditions for the second drying include: a second drying temperature of 80℃~120℃ and a second drying time of 10h~12h; More preferably, the calcination conditions include: a calcination temperature of 500℃~650℃ and a calcination time of 3h~5h.

9. The application of the metal-modified mordenite molecular sieve catalyst of claim 7 or the catalyst regenerated by the regeneration method of claim 8 in the preparation method of diisopropylnaphthalene.

10. A method for preparing diisopropylnaphthalene, characterized in that, The steps include: reacting monoisopropylnaphthalene in the presence of the metal-modified mordenite molecular sieve catalyst of claim 7 or the catalyst regenerated by the regeneration method of claim 8 to obtain diisopropylnaphthalene; Preferably, The reaction temperature is 150-400℃. And / or, the reaction pressure is 1.0-3.5 MPa. And / or, the space velocity of the reaction is 1000-12000 mL / h / g. And / or, the amount of the metal-modified mordenite molecular sieve catalyst or the catalyst regenerated by the regeneration method is 0.5-10 wt% of the mass of monoisopropylnaphthalene.

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