CN111495419A - A metal-supported multi-stage porous ZSM-5 molecular sieve and its preparation method and application - Google Patents

Abstract

The application discloses a metal-loaded hierarchical pore ZSM-5 molecular sieve, which contains mesopores, wherein the average pore diameter of the mesopores is 2-20 nm, the pore volume of the mesopores is 0.2-0.6 m L/g, metal elements in the metal-loaded hierarchical pore ZSM-5 molecular sieve are selected from at least one of Sn, Mg and Zn, the metal element loading amount is 0.1-10 wt%, and the metal loading amount is calculated by the metal element loading amount.

Description

A metal-supported multi-stage porous ZSM-5 molecular sieve and its preparation method and application

technical field

The present application relates to a metal-supported hierarchical porous ZSM-5 molecular sieve and a preparation method thereof, as well as the preparation of 2,5-furandimethanol by catalyzing the etherification of 2,5-furandimethanol and ethanol as a catalyst in a fixed bed reactor The application in the method of ethyl ether belongs to the field of molecular sieves.

Background technique

5-Ethoxymethylfurfural (EMF) is a product of etherification of 5-hydroxymethylfurfural (HMF) with ethanol, due to its high energy density (8.7kW h L ^-1 ) and good fuel mixability, Considered a potential bio-based fuel additive. At present, there have been many reports on the etherification of HMF with ethanol and other monohydric alcohols to prepare monoethers, and the relationship between this reaction and catalyst acidity has also been deeply understood. However, there is still an aldehyde group in the EMF molecule, which reduces the stability of the molecule. 2,5-Furandimethanol diethyl ether (BEMF) is first prepared by catalytic hydrogenation of HMF to 2,5-furandimethanol (BHMF), which is then prepared by etherification with ethanol. Compared with EMF, BEMF not only has higher stability, but also has a wider carbon number range and wider application range. Solid acid catalysts, especially molecular sieves and Amberlyst-15, are widely used to catalyze the etherification of BHMF with monohydric alcohols to prepare 2,5-furandimethanol dialkyl ether (BAMF). The literature [AppliedCatalysis A: General 481, 49-53 (2014)] reported that ZSM-5 molecular sieve was used as a catalyst to catalyze the etherification reaction of 2,5-furandimethanol with methanol. Under the optimized reaction conditions, 2,5-furan The highest yield of dimethanol dimethyl ether was 70%. Literature [Synlett, 28, 2299-2302 (2017)] reported the performance of Amberlyst-15 catalyzing the etherification of 2,5-furandimethanol and ethanol to prepare 2,5-furandimethanol diethyl ether, 2,5-furan The yield of dimethanol diethyl ether reached 70%. It is worth noting that the above documents are all carried out in batch reactors. Compared with the tank reactor, the fixed bed reactor can greatly shorten the production time, and the operation is simple, which is more suitable for continuous production. However, due to the shorter reaction time of reactant molecules in contact with the catalyst in the fixed-bed reaction, higher requirements are placed on the activity, selectivity and stability of the catalyst. Both ZSM-5 molecular sieves and Amberlyst-15 reported in the literature are reacted at lower temperature (<80°C) for 3-24 hours. Although increasing the reaction temperature can speed up the reaction rate, it also greatly reduces the selectivity of the target product.

Therefore, a high-performance fixed-bed catalyst that can be effectively used in the etherification reaction of 2,5-furandimethanol and ethanol to prepare 2,5-furandimethanol diethyl ether was developed to achieve high 2,5-furandimethanol diethyl ether. Diethyl ether yield and excellent catalyst stability are of great interest.

SUMMARY OF THE INVENTION

According to one aspect of the present application, there is provided a metal-supported hierarchically porous ZSM-5 molecular sieve, the molecular sieve is hierarchically porous, has high activity, selectivity and excellent stability, and has good application in the field of catalysts prospect.

The metal-loaded multi-stage porous ZSM-5 molecular sieve is characterized in that the metal-loaded multi-stage porous ZSM-5 molecular sieve contains mesopores;

The average pore diameter of the mesopores is 2-20 nm, and the mesopore pore volume is 0.2-0.6 mL/g;

The metal element in the metal-loaded multi-stage porous ZSM-5 molecular sieve is selected from at least one of Sn, Mg, and Zn, and the metal element loading is 0.1wt% to 10wt%;

The metal loading is calculated as the loading of metal elements.

Optionally, the metal element in the metal-loaded multi-stage porous ZSM-5 molecular sieve is one of Sn, Mg, and Zn, and the metal element loading is 1wt% to 5wt%;

The metal loading is calculated as the loading of metal elements.

Optionally, the multi-stage porous ZSM-5 molecular sieve has a particle size of 100-400 nm, a specific surface area of 400-700 m ² /g, and a silicon-aluminum atomic ratio of 10-500.

Optionally, the lower limit of the range of the Si/Al atomic ratio (the atomic molar ratio of Si/Al) of the hierarchically porous ZSM-5 molecular sieve is selected from 10, 20 or 30, and the upper limit is selected from 50, 300 or 500.

Optionally, the atomic ratio of silicon to aluminum (atomic ratio of Si/Al) of the hierarchically porous ZSM-5 molecular sieve is 30-300.

Optionally, the silicon-alumina ratio (atomic ratio of Si/Al) of the hierarchically porous ZSM-5 molecular sieve is 30-150.

According to another aspect of the present application, there is provided a preparation method of the metal-supported multi-stage porous ZSM-5 molecular sieve, which is simple, low in energy consumption and suitable for industrial production.

The described method for preparing metal-loaded multi-stage porous ZSM-5 molecular sieve is characterized in that comprising the following steps:

1) making the raw material containing silicon source, aluminum source, template agent and alcohol compound into xerogel;

2) Under airtight conditions, the xerogel is crystallized in an atmosphere containing water vapor to obtain a multi-level porous ZSM-5 molecular sieve;

3) Impregnating the hierarchically porous ZSM-5 molecular sieve in a solution containing a metal element precursor, and then drying and calcining to obtain the metal-supported hierarchically porous ZSM-5 molecular sieve.

Optionally, the silicon source is selected from at least one of ethyl orthosilicate, methyl orthosilicate, hexadecyltrimethoxysilane, and octadecyltrimethoxysilane.

Optionally, the aluminum source is selected from at least one of organoaluminum compounds.

Optionally, the aluminum source is aluminum isopropoxide.

Optionally, the templating agent is selected from at least one of the compounds with the chemical structural formula shown in formula II:

In formula II, R ₅ , R ₆ , R ₇ , R ₈ are independently selected from methyl, ethyl, propyl or butyl;

X ^— is selected from at least one of OH ^— , F ^— , Cl ^— , Br ^— and I ^— .

Optionally, the templating agent is tetrapropylammonium hydroxide (abbreviated as TPAOH).

Optionally, the alcohol compound is selected from at least one of ethanol and isopropanol.

Optionally, the alcohol compound is ethanol.

Optionally, the molar ratio of silicon source, aluminum source, templating agent and alcohol compound in the raw material of step 1) is:

Silicon source: aluminum source: templating agent: alcohol compound = 1.01-1.1: 0.002-0.1: 0.1-0.3: 10-1000.

Optionally, the molar ratio of silicon source, aluminum source, templating agent and alcohol compound in the raw material is:

Silicon source: aluminum source: templating agent: alcohol compound=1.05:0.002～0.1:0.2:20.

Optionally, the molar ratio of silicon source, aluminum source, templating agent and alcohol compound in the raw material is:

Silicon source: aluminum source: templating agent: alcohol compound = 1.05:0.0035:0.2:20.

Among them, the mole number of silicon source is calculated as SiO ₂ , the mole number of aluminum source is calculated as Al ₂ O ₃ , the number of moles of template agent is calculated as the number of moles of template agent itself, and the number of moles of alcohol compound is calculated as the number of moles of alcohol compound itself. mole count.

Optionally, the xerogel described in step 1) is prepared by a method comprising the following steps:

Mixing silicon source, aluminum source, templating agent and alcohol compound to obtain raw gel;

The obtained raw gel is dried at 20-40° C. for not less than 24 hours to obtain the xerogel.

Optionally, the gel drying time is 72h to form a dry gel.

Optionally, step 1) includes: stirring the raw material containing the silicon source, the aluminum source, the templating agent and the alcohol compound at 25° C. to form a gel, and then drying to form a xerogel.

Optionally, in the step 2), the crystallization time of the xerogel in the atmosphere containing water vapor is 48-120 h, and the crystallization temperature is 150°C-200°C.

Optionally, the atmosphere containing water vapor is a water vapor atmosphere.

Optionally, the crystallization time in the step 2) is 60-96 h.

Optionally, the crystallization temperature in the step 2) is 160°C to 190°C.

Optionally, the crystallization in the step 2) is crystallization at 150°C to 200°C for 60 to 96 hours.

Optionally, the crystallization in the step 2) is crystallization at 160°C to 190°C for 70 to 80 hours.

Optionally, step 2) includes: under airtight conditions, crystallization of the xerogel in an atmosphere containing water vapor, and washing, drying and calcining after the crystallization is completed to obtain a multi-stage porous ZSM-5 molecular sieve.

Optionally, the drying conditions in step 2) are drying at 110° C. for 2-4 hours.

Optionally, the calcination condition in step 2) is calcination at 550° C. for 5-12 h.

Optionally, the metal in the metal precursor in step 3) is selected from at least one of Sn, Mg, and Zn;

The impregnation is an equal volume impregnation method, and the metal loading is 0.1 wt % to 10 wt %.

Optionally, the metal element precursor is selected from Sn chloride, Sn sulfate, Sn nitrate, Mg chloride, Mg sulfate, Mg nitrate, Zn chloride, Zn sulfuric acid At least one of salt and Zn nitrate.

Optionally, the metal element precursor is selected from at least one of stannous chloride dihydrate, magnesium nitrate hexahydrate, and zinc nitrate hexahydrate.

Optionally, the metal loading in step 3) is 1 wt % to 5 wt %.

Optionally, the drying conditions in step 3) are drying at 110° C. for 2-4 hours.

Optionally, the calcination condition in step 3) is calcination at 550° C. for 5-12 h.

According to another aspect of the present application, a catalyst is provided, which has high activity and selectivity and excellent stability, and whose hierarchical pore structure and suitable surface acidity can improve the efficiency of the target product.

The catalyst is characterized in that it comprises a metal-supported multi-level porous ZSM-5 molecular sieve;

The metal-supported hierarchical porous ZSM-5 molecular sieve is selected from at least one of the metal-supported hierarchical porous ZSM-5 molecular sieve and the metal-supported hierarchical porous ZSM-5 molecular sieve prepared according to the method .

Optionally, the particle size of the catalyst is 20-40 meshes.

According to another aspect of the present application, a method for synthesizing 2,5-furandimethanol dialkyl ether is provided. The catalyst of the reaction method has the characteristics of high conversion rate, high yield of target product and good stability.

The method for synthesizing the 2,5-furandimethanol dialkyl ether is characterized in that the reaction raw material containing 2,5-furandimethanol and an alkyl alcohol is passed into a fixed bed reactor equipped with a catalyst, and the reaction raw material is Contact reaction with catalyst to prepare 2,5-furandimethanol dialkyl ether;

The alkyl alcohol has the structural formula shown in formula I: R-OH formula I; wherein, R is a C ₂ -C ₁₀ alkyl group;

The catalyst is selected from at least one of the metal-supported hierarchical porous ZSM-5 molecular sieve, the metal-supported hierarchical porous ZSM-5 molecular sieve prepared according to the method, and the catalyst.

Optionally, the alkyl alcohol is ethanol.

Optionally, the method for synthesizing the 2,5-furandimethanol dialkyl ether is characterized in that the reaction raw materials containing 2,5-furandimethanol and alkyl alcohol are passed into a fixed bed reaction equipped with a catalyst The reaction raw material is contacted and reacted with the catalyst to continuously prepare 2,5-furandimethanol dialkyl ether;

The alkyl alcohol has the structural formula shown in formula I: R-OH formula I; wherein, R is a C ₁ -C ₁₀ alkyl group;

The catalyst is selected from at least one of the metal-supported hierarchical porous ZSM-5 molecular sieve, the metal-supported hierarchical porous ZSM-5 molecular sieve prepared according to the method, and the catalyst.

Optionally, the alkyl alcohol is ethanol.

Optionally, the concentration of 2,5-furandimethanol in the reaction raw material is 1-50 g/L.

Optionally, the concentration of 2,5-furandimethanol in the material is 5 g/L.

Optionally, the upper limit of the concentration of 2,5-furandimethanol in the reaction raw material is selected from 2g/L, 3g/L, 4g/L, 5g/L, 10g/L, 15g/L, 20g/L, 30g /L, 40g/L or 50g/L; the lower limit is selected from 1g/L, 2g/L, 3g/L, 4g/L, 5g/L, 10g/L, 15g/L, 20g/L, 30g/L or 40g/L.

Optionally, the mass space velocity of the 2,5-furandimethanol is 0.1˜3 h ⁻¹ .

Optionally, the upper limit of the mass space velocity of the 2,5-furandimethanol is selected from 0.2h ^-1 , 0.3h ^-1 , 0.5h ^-1 , 1h ^-1 , 1.5h ^-1 , 2h ^-1 , 2.5h ^-1 or 3h ^-1 ; the lower limit is selected from 0.1h ^-1 , 0.2h ^-1 , 0.3h ^-1 , 0.5h ^-1 , 1h ^-1 , 1.5h ^-1 , 2h ^-1 or 2.5h ^-1 .

Optionally, the mass space velocity of the 2,5-furandimethanol is 0.3 h ⁻¹ .

Optionally, the mass space velocity of the 2,5-furandimethanol is 0.2 h ⁻¹ .

Optionally, the reaction temperature for the contact reaction between the reaction raw material containing 2,5-furandimethanol and monohydric alcohol and the catalyst is 100-160°C.

Optionally, the upper limit of the reaction temperature of the contact reaction between the reaction raw materials containing 2,5-furandimethanol and monohydric alcohol and the catalyst is selected from 110°C, 120°C, 130°C, 140°C, 150°C or 160°C; the lower limit Selected from 100°C, 110°C, 120°C, 130°C, 140°C or 150°C.

Optionally, the reaction temperature for the contact reaction of the reaction raw material containing 2,5-furandimethanol and monohydric alcohol with the catalyst is 140°C.

Optionally, the reaction pressure for the contact reaction between the reaction raw material containing 2,5-furandimethanol and monohydric alcohol and the catalyst is 0.1-3 MPa.

Optionally, the upper limit of the reaction pressure for the contact reaction between the reaction raw materials containing 2,5-furandimethanol and monohydric alcohol and the catalyst is selected from 0.5MPa, 1MPa, 1.5MPa, 2MPa, 2.5MPa or 3MPa; the lower limit is selected from 0.1 MPa, 0.5MPa, 1MPa, 1.5MPa, 2MPa or 2.5MPa.

Optionally, the reaction pressure for the contact reaction between the reaction raw material containing 2,5-furandimethanol and monohydric alcohol and the catalyst is 2 MPa.

Optionally, the reacted catalyst is calcined to obtain a regenerated catalyst.

As an embodiment, a method for synthesizing 2,5-furandimethanol diethyl ether is provided. The catalyst of the reaction method has the characteristics of high conversion rate, high yield of target product and good stability.

The method for synthesizing 2,5-furandimethanol diethyl ether is characterized in that the catalyst is placed in a fixed-bed reactor, and then the mixed solution of 2,5-furandimethanol and ethanol is mixed with a high-pressure constant-flow pump After the reactant and the catalyst are contacted and reacted under certain reaction conditions, 2,5-furandimethanol diethyl ether is prepared.

Optionally, the concentration of 2,5-furandimethanol in the material is 1-50 g/L.

Optionally, the concentration of 2,5-furandimethanol in the material is 5 g/L.

Optionally, the mass space velocity of the 2,5-furandimethanol is 0.1˜3 h ⁻¹ .

Optionally, the mass space velocity of the 2,5-furandimethanol is 0.3 h ⁻¹ .

Optionally, the reaction temperature for the contact reaction between the mixed solution and the catalyst is 100-160°C.

Optionally, the reaction pressure for the contact reaction between the mixed solution and the catalyst is 0.1-3 MPa.

In this application, tetrapropylammonium hydroxide is abbreviated as TPAOH.

In this application, hexadecyltrimethoxysilane is abbreviated as HTS.

In this application, 2,5-furandimethanol diethyl ether is abbreviated as BEMF.

In this application, 2,5-furandimethanol is abbreviated as BHMF.

In the present application, C ₂ to C ₁₀ refer to the number of carbon atoms contained. For example, "C ₂ -C ₁₀ alkyl group" refers to an alkyl group containing 2-10 carbon atoms.

In this application, "alkyl" is a group formed by the loss of any hydrogen atom on the molecule of an alkane compound. The alkane compounds include straight-chain alkanes, branched-chain alkanes, cycloalkanes, and cycloalkanes with branched chains.

The beneficial effects that this application can produce include:

1) The metal-supported hierarchical porous ZSM-5 molecular sieve provided by this application has both mesopores and micropores, and has excellent catalytic performance. The existence of mesopores can effectively improve the utilization rate of catalyst acid sites and promote the production of macromolecular products. Diffusion, which has good application prospects in the field of catalysts;

2) The preparation method of the metal-loaded multi-stage porous ZSM-5 molecular sieve provided by the present application has the characteristics of simplicity, low energy consumption, and suitability for industrial production.

3) The metal-supported hierarchical porous ZSM-5 molecular sieve catalyst provided by the present application can effectively inhibit the occurrence of side reactions such as ring opening and polymerization in the process of catalyzing the etherification of molecules such as 2,5-furandimethanol.

4) The method for the etherification reaction of 2,5-furandimethanol and ethanol provided in this application has high conversion activity of 2,5-furandimethanol, high yield of 2,5-furandimethanol diethyl ether and Excellent stability; the metal-supported hierarchical porous ZSM-5 molecular sieve catalyst of the reaction method is not easy to be deactivated, and can be calcined and regenerated.

Description of drawings

Figure 1 is the XRD pattern of the sample CAT-2 ^# .

Fig. 2 is the catalytic performance test result of the sample CAT-2 ^# in Example 9.

Detailed ways

The present application will be described in detail below with reference to the examples, but the present application is not limited to these examples.

Unless otherwise specified, the raw materials, solvents and microporous molecular sieve catalysts in the examples of the present application are all purchased through commercial channels, wherein the microporous molecular sieve catalysts are purchased from Nankai University Catalyst Factory.

In the examples, the X-ray powder diffraction of the samples was carried out with a D8ADVANCE powder diffractometer from Bruker, using a Cu Kα radiation source.

In the embodiment, the product in the synthesis reaction of 2,5-furandimethanol diethyl ether was analyzed by using Agilent's 1260 high performance liquid chromatograph.

The conversion rate and yield in the synthesis reaction of 2,5-furandimethanol diethyl ether are calculated as follows:

The purity of the 2,5-furandimethanol diethyl ether product is the weight percentage content of the target product 2,5-furandimethanol dimethyl ether in the reaction product. Both BHMF conversion and BMMF yield are calculated based on moles of carbon:

Example 1 Sample 1 ^# Preparation

Mix 0.12g of aluminum isopropoxide, 12g of tetrapropylammonium hydroxide, 14mL of ethyl orthosilicate, 1.6mL of hexadecyltrimethoxysilane and 50mL of ethanol in a beaker, and stir at 25°C until a gel is formed; The gel was dried at 25 °C for 48 h and placed in a 50 mL liner, which was then transferred to a 250 mL stainless steel hydrothermal kettle containing a Teflon liner, and 60 mL of deionized water was added between the two liners to provide In the water vapor atmosphere required for crystallization, crystallize at 180 °C for 72 hours; after filtering, washing, drying at 110 °C for 3 hours, and calcining at 550 °C for 7 hours, the hierarchical porous ZSM-5 molecular sieve sample is obtained. for sample 1 ^# .

Example 2 Sample 2 ^# Preparation

Mix 0.12g of aluminum isopropoxide, 12g of tetrapropylammonium hydroxide, 14mL of ethyl orthosilicate, 1.6mL of hexadecyltrimethoxysilane and 50mL of ethanol in a beaker, and stir at 25°C until a gel is formed; The gel was dried at 25 °C for 48 h and placed in a 50 mL liner, which was then transferred to a 250 mL stainless steel hydrothermal kettle containing a Teflon liner, and 60 mL of deionized water was added between the two liners to provide In the water vapor atmosphere required for crystallization, crystallize at 180 °C for 72 hours; after filtering, washing, drying at 110 °C for 3 hours, and calcining at 550 °C for 7 hours, the hierarchical porous ZSM-5 molecular sieve 1 ^# sample is obtained . Take 0.1g of stannous chloride dihydrate and add it to 4g of deionized water, then add 4g of multi-level porous ZSM-5 molecular sieve 1 ^# to soak for 48h, and after drying and calcining at 550 ° C for 7 hours, the metal tin-supported multi-component is obtained. The graded pore ZSM-5 molecular sieve sample is denoted as sample 2 ^# .

Example 3 Preparation of Sample 3 ^#

Mix 0.10 g of aluminum isopropoxide, 12 g of tetrapropylammonium hydroxide, 14 mL of ethyl orthosilicate, 1.6 mL of hexadecyltrimethoxysilane and 50 mL of ethanol in a beaker, and stir at 25°C until a gel is formed; The gel was dried at 25 °C for 48 h and placed in a 50 mL liner, which was then transferred to a 250 mL stainless steel hydrothermal kettle containing a Teflon liner, and 50 mL of deionized water was added between the two liners to provide The water vapor atmosphere required for crystallization was crystallized at 175°C for 72h; after filtration, washing, drying at 110°C for 2h, and calcination at 550°C for 6h, the hierarchical porous ZSM-5 molecular sieve sample was obtained. for sample 3 ^# .

Example 4 Preparation of Sample 4 ^#

Mix 0.10 g of aluminum isopropoxide, 12 g of tetrapropylammonium hydroxide, 14 mL of ethyl orthosilicate, 1.6 mL of hexadecyltrimethoxysilane and 50 mL of ethanol in a beaker, and stir at 25°C until a gel is formed; The gel was dried at 25 °C for 48 h and placed in a 50 mL liner, which was then transferred to a 250 mL stainless steel hydrothermal kettle containing a Teflon liner, and 50 mL of deionized water was added between the two liners to provide The water vapor atmosphere required for crystallization was crystallized at 175°C for 72h; after filtration, washing, drying at 110°C for 2h, and calcination at 550°C for 6h, the hierarchical porous ZSM-5 molecular sieve 3 ^# sample was obtained . Take 0.85g of magnesium nitrate hexahydrate and add it to 3g of deionized water, then add 3g of multi-porous ZSM-5 molecular sieve 3 ^# to soak for 24h, dry at 110°C for 2h and calcinate at 550°C for 8h to obtain the metal magnesium supported type The multi-stage porous ZSM-5 molecular sieve sample is recorded as sample 4 ^# .

Example 5 Preparation of Sample 5 ^#

Mix 0.06 g of aluminum isopropoxide, 12 g of tetrapropylammonium hydroxide, 14 mL of ethyl orthosilicate, 1.6 mL of octadecyltrimethoxysilane and 50 mL of ethanol in a beaker, and stir at 25°C until a gel is formed; The gel was dried at 25 °C for 72 h and placed in a 50 mL liner, which was then transferred to a 250 mL stainless steel hydrothermal kettle containing a Teflon liner, and 40 mL of deionized water was added between the two liners to provide The water vapor atmosphere required for crystallization was crystallized at 180 °C for 70 hours; after filtration, washing, drying at 110 °C for 4 hours, and calcination at 550 °C for 8 hours, the hierarchical porous ZSM-5 molecular sieve sample was obtained. Recorded as sample 5 ^# .

Example 6 Preparation of Sample 6 ^#

Mix 0.06 g of aluminum isopropoxide, 12 g of tetrapropylammonium hydroxide, 14 mL of ethyl orthosilicate, 1.6 mL of octadecyltrimethoxysilane and 50 mL of ethanol in a beaker, and stir at 25°C until a gel is formed; The gel was dried at 25 °C for 72 h and placed in a 50 mL liner, which was then transferred to a 250 mL stainless steel hydrothermal kettle containing a Teflon liner, and 40 mL of deionized water was added between the two liners to provide The water vapor atmosphere required for crystallization is crystallized at 180°C for 70h; after filtration, washing, drying at 110°C for 4h, and calcination at 550°C for 8h, the hierarchical porous ZSM-5 molecular sieve 5 ^# sample. Take 0.1g of zinc nitrate hexahydrate and add it to 4g of deionized water, then add 4g of multi-level porous ZSM-5 molecular sieve 5 ^# to soak for 36 hours, dry at 110 °C for 2 hours, and bake at 550 °C for 6 hours to obtain the metal zinc-supported multistage Pore ZSM-5 molecular sieve sample, denoted as sample 6 ^# .

Example 7 Preparation of samples 7 ^# to 9 ^#

The preparation method of sample 7 ^# is the same as that of embodiment 1, the difference is that the addition amount of aluminum isopropoxide is 0.4g.

The preparation method of sample 8 ^# is the same as that of Example 2, except that the addition amount of stannous chloride dihydrate is 0.5 g.

The preparation method of sample 9 ^# is the same as that of Example 6, except that the addition amount of zinc nitrate hexahydrate is 0.5 g.

Characterization of Example 8 Samples

The samples 1 ^# ~ 9 ^# and CAT-1 ^# ~ CAT-9 ^# were characterized by X-ray powder diffraction, and the results showed that the samples 1 ^# ~ 9 ^# and CAT-1 ^# ~ CAT-9 ^# were all ZSM-5 Molecular sieve, represented by CAT-2 ^# , its XRD pattern is shown in Figure 1, the results of samples 1 ^# ~ 9 ^# and CAT-1 ^# , CAT-3 ^# ~ CAT-9 ^# are similar to Figure 1, the diffraction peaks The peak positions were substantially the same, and the peak intensity of each diffraction peak varied within a range of ±10% depending on the preparation conditions.

Samples 1 ^# to 9 ^# were characterized by X-ray fluorescence spectroscopy (XRF) and an automatic specific surface area and porosity analyzer. The atomic ratio of molecular sieve to silicon and aluminum was 30 to 200, and the mesopore diameter was 2 to 20 nm. The mesoporous pore volume is 0.2-0.6 mL/g.

The samples 1 ^# to 9 ^# of the examples were characterized by scanning electron microscopy (SEM), and the particle size of the molecular sieve was 100 to 400 nm.

The samples 1 ^# to 9 ^# of the examples were characterized by an automatic specific surface analyzer, and the specific surface area of the molecular sieve was 400 to 700 m ² /g.

Example 9 Preparation of CAT-1 ^# to CAT-9 ^#

The obtained samples 1 ^# to 9 ^# were ground, tableted, crushed and sieved, and the particle sizes of 20 to 40 mesh were taken as catalyst samples, which were recorded as CAT-1 ^# to CAT-9 ^# respectively.

Comparative Example 1 Preparation of DCAT-1 ^# and DCAT-2 ^#

ZSM-5 (Si/Al=50), MCM-22 (Si/Al=25) and Mordenite (Si/Al=11) molecular sieves purchased from Nankai Catalyst Factory were placed at 550 ° C for calcination for 8h, respectively. The catalyst was ground, tableted, crushed and sieved, and the particle size of 20-40 mesh was taken as catalyst samples, which were recorded as DCAT-1 ^# , DCAT-2 ^# and DCAT-3 ^# respectively.

Example 10 Application of catalyst sample in the synthesis of 2,5-furandimethanol diethyl ether

CAT-1 ^# to CAT-9 ^# , DCAT-1 ^# , DCAT-2 ^# and DCAT-3 ^# were respectively used for the synthesis reaction of 2,5-furandimethanol diethyl ether, and the specific steps were as follows:

Weigh 5g of 2,5-furandimethanol and make up to 1L with ethanol. Weigh 2g of catalyst and place it in the fixed-bed reactor, feed hydrogen as the carrier gas, the pressure is 2Mpa, heat up to 140°C and hold for 30min; then use the high-pressure constant-flow pump to pump the raw material into the fixed-bed reactor, 2,5- The mass space velocity of furandimethanol was 0.3 h ⁻¹ ; sampling was started after 1 h of reaction, and then every 1 h was sampled, and feeding was stopped after 6 h of reaction. The samples taken were diluted with methanol and the concentrations of reactants and products were analyzed by high performance liquid chromatography, and then the conversion rate of 2,5-furandimethanol and the yield of 2,5-furandimethanol diethyl ether were calculated, as shown in Table 1 shown. Samples 1 ^# , 3 ^# and 5 ^# are unsupported multi-stage porous molecular sieves, while samples 2 ^# , 4 ^# and 6 ^# are metal loaded on the corresponding unsupported multi-stage porous molecular sieves. It can be seen from Table 1 that the load The performance of the catalysts was better than that of the unsupported catalysts. In this application, metal-supported hierarchical porous ZSM-5 molecular sieve is used to synthesize 2,5-furandimethanol dialkyl ether with 2,5-furandimethanol and methanol as raw materials, and the conversion rate of 2,5-furandimethanol Achieving 100%, the yield of 2,5-furandimethanol diethyl ether was as high as 90%.

Table 1 Catalytic performance of microporous ZSM-5 and hierarchically porous ZSM-5 molecular sieves

BHMF: 2,5-furandimethanol; BEMF: 2,5-furandimethanol diethyl ether

Example 11 Stability of catalyst samples

The catalyst sample CAT-2 ^# was used as a catalyst for the synthesis of 2,5-furandimethanol diethyl ether. The specific steps and conditions were the same as those in Example 10, except that the reaction was continued after 6h of reaction, and sampling was performed every one hour. , the feeding was stopped after 100h of reaction. Fig. 2 is a graph showing the catalytic activity and stability of the fixed-bed reactor for 100 hours of continuous feeding reaction. Fig. 2 shows that the catalyst maintains good catalytic activity and stability during the investigated reaction time. When a fixed-bed reactor is used, the catalyst is fixedly packed in the reaction tube, and the reaction material is continuously injected by the high-pressure constant-flow pump, and the reaction product can be continuously obtained. The 100h in the stability study is the target product after 100h of continuous feeding. The yield remained above 90% and even reached 96% in the later stage. Therefore, the present invention adopts the metal-supported multi-stage porous molecular sieve to realize continuous production on the fixed bed reactor.

The stability effects of catalysts CAT-1 ^# , CAT-3 ^# ~ CAT-9 ^# and catalyst CAT-2 ^# are similar.

The above are only a few embodiments of the present application, and are not intended to limit the present application in any form. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Without departing from the scope of the technical solution of the present application, any changes or modifications made by using the technical content disclosed above are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims (10)

1. A metal-loaded multi-stage hole ZSM-5 molecular sieve, wherein the metal-loaded multi-stage hole ZSM-5 molecular sieve contains mesopores; The average pore diameter of the mesopores is 2-20 nm, and the mesopore pore volume is 0.2-0.6 mL/g; The metal element in the metal-loaded multi-stage porous ZSM-5 molecular sieve is selected from at least one of Sn, Mg, and Zn, and the metal element loading is 0.1wt% to 10wt%; The metal loading is calculated as the loading of metal elements. 2 . The metal-supported multi-stage porous ZSM-5 molecular sieve according to claim 1 , wherein the multi-stage porous ZSM-5 molecular sieve has a particle size of 100-400 nm and a specific surface area of 400-700 m ² /g , the atomic ratio of silicon to aluminum is 10 to 500. 3. a method for preparing metal-loaded multi-stage porous ZSM-5 molecular sieve, is characterized in that, comprises the following steps: 1) making the raw material containing silicon source, aluminum source, template agent and alcohol compound into xerogel; 2) Under airtight conditions, the xerogel is crystallized in an atmosphere containing water vapor to obtain a multi-level porous ZSM-5 molecular sieve; 3) Impregnating the hierarchically porous ZSM-5 molecular sieve in a solution containing a metal element precursor, and then drying and calcining to obtain the metal-supported hierarchically porous ZSM-5 molecular sieve. 4. method according to claim 3, is characterized in that, the mol ratio of silicon source, aluminium source, templating agent and alcohol compound in the described raw material of step 1) is: Silicon source: aluminum source: template agent: alcohol compound = 1.01-1.1: 0.002-0.1: 0.1-0.3: 10-1000; Among them, the mole number of silicon source is calculated as SiO ₂ , the mole number of aluminum source is calculated as Al ₂ O ₃ , the number of moles of template agent is calculated as the number of moles of template agent itself, and the number of moles of alcohol compound is calculated as the number of moles of alcohol compound itself. mole count; Preferably, the xerogel in step 1) is prepared by a method comprising the following steps: Mixing silicon source, aluminum source, templating agent and alcohol compound to obtain raw gel; The obtained raw gel is dried at 20-40° C. for not less than 24 hours to obtain the xerogel. 5 . The method according to claim 3 , wherein the crystallization time in the step 2) is 48-120 h, and the crystallization temperature is 150° C. to 200° C. 6 . Preferably, the crystallization time in the step 2) is 60-96h; Preferably, the temperature of the crystallization in the step 2) is 160°C to 190°C. 6. method according to claim 3, is characterized in that, described metal element in described step 3) is selected from at least one in Sn, Mg, Zn; Preferably, the metal element precursor is selected from Sn chloride, Sn sulfate, Sn nitrate, Mg chloride, Mg sulfate, Mg nitrate, Zn chloride, Zn sulfate , at least one of the nitrates of Zn; The impregnation in step 3) is an equal volume impregnation method, and the metal loading is 0.1wt% to 10wt%; Preferably, in step 3), the metal loading is 1wt% to 5wt%; The metal loading is calculated as the loading of metal elements. 7. a catalyzer is characterized in that, comprises metal-loaded multi-stage porous ZSM-5 molecular sieve; The metal-supported multi-stage pore ZSM-5 molecular sieve is selected from the metal-supported multi-stage pore ZSM-5 molecular sieve according to claim 1 or 2, and the metal-supported molecular sieve prepared according to the method of any one of claims 3 to 6. At least one of the multi-stage porous ZSM-5 molecular sieves. 8. a synthetic method of 2,5-furandimethanol dialkyl ether, is characterized in that, the reaction raw material that contains 2,5-furandimethanol and alkyl alcohol is passed into the fixed bed reactor equipped with catalyst, The reaction raw material is contacted and reacted with the catalyst to prepare 2,5-furandimethanol dialkyl ether; The alkyl alcohol has the structural formula shown in formula I: R-OH formula I; wherein, R is a C ₂ -C ₁₀ alkyl group; The catalyst is selected from the metal-supported hierarchically porous ZSM-5 molecular sieve according to claim 1 or 2, the metal-supported hierarchically porous ZSM-5 molecular sieve prepared according to the method of any one of claims 3 to 6, At least one of the catalysts of claim 7. 9 . The method for synthesizing 2,5-furandimethanol dialkyl ether according to claim 8 , wherein the alkyl alcohol is ethanol. 10 . 10. The method for synthesizing 2,5-furandimethanol dialkyl ether according to claim 8, wherein the concentration of 2,5-furandimethanol in the reaction raw material is 1-50 g/L; Preferably, the mass space velocity of the 2,5-furandimethanol is 0.1～3h ⁻¹ ; Preferably, the reaction temperature for the contact reaction between the reaction raw material containing 2,5-furandimethanol and alkyl alcohol and the catalyst is 100-160°C; Preferably, the reaction pressure for the contact reaction of the reaction raw material containing 2,5-furandimethanol and alkyl alcohol with the catalyst is 0.1-3 MPa.

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