Preparation method of Ag-MoOx bimetallic catalyst, Ag-MoOx bimetallic catalyst and application

Abstract

The application discloses an Ag-MoO x A preparation method of a bimetallic catalyst, an Ag-MoO x A bimetallic catalyst and application, the preparation method comprises the following steps: after a mixture containing a molecular sieve, an alkali source, a silver source and a molybdenum source is impregnated, dried and calcined, the Ag-MoO x A bimetallic catalyst; wherein the impregnation comprises the following steps: the molecular sieve and the alkali source are first impregnated and treated, and then impregnated with a solution containing the silver source and the molybdenum source, or the molecular sieve, the silver source and the molybdenum source are first impregnated and treated, and then impregnated with the alkali source. The application is greatly improved in the production efficiency of 2-methylpropenol by being matched with a continuous reactor-fixed bed. Under the condition that hydrogen is used as a reducing agent and without a solvent, the conversion rate of methylpropenal on the bimetallic catalyst reaches 82%, the selectivity of 2-methylpropenol is 89%, and meanwhile, the catalyst can be stably operated for a longer time.

Description

TECHNICAL FIELD

[0001] The application relates to an Ag-MoO x Preparation method of bimetallic catalyst, Ag-MoO x Bimetallic catalyst and application, and belongs to the technical field of chemical industry. BACKGROUND

[0002] 2-methyl propenol is widely used in the production of polymer monomers, surfactants, synthetic resin additives, and polycarboxylic acid superplasticizer, and is an important fine chemical product.

[0003] According to the process of the reaction, the current production method of 2-methyl propenol is divided into four kinds: 1, chlor-alkali method, 2, hydrogen transfer method, 3, selective hydrogenation method and 4, dehydration method. Among them, the chlor-alkali method is the most widely used method in the actual industrial production. The method first generates isobutylene chloride through the substitution reaction of isobutylene and chlorine, and then generates 2-methyl propenol through the hydroxyl substitution reaction in a strong alkali environment. Compared with the above three methods, the selective hydrogenation is a more efficient and environmentally friendly method. Although some invention patents (CN102167657B, CN106631691A, CN107056566A) based on the method have been reported, the use of a large amount of solvent in the process, the use of a batch reactor, and the high cost of catalyst preparation highlight the problem, which causes certain obstacles to the actual industrial application.

[0004] The C4 by-product isobutylene in coal chemical industry and petroleum chemical industry is low in price, and with the development of the process of preparing aldehyde by oxidation, it has been successfully applied in the industrial field. The application of the technology makes the process of preparing methyl propenol from methyl propenal develop rapidly. Under the action of the catalyst, the hydroxyl H atom on the small molecule alcohol is transferred to the carbonyl group of methyl propenal to generate methyl propenol and the corresponding aldehyde or ketone. Some literatures and patents show that the greater the polarity of the alcohol, the more conducive to the generation of unsaturated alcohol, and generally the activity order is as follows: isopropyl alcohol>ethanol>2-butanol>2-pentanol>methyl alcohol. At present, the two-step process of preparing methyl propenol from isobutylene developed by the Institute of Process of Chinese Academy of Sciences and Shandong Yidali Chemical Co., Ltd. has realized industrialized production. The first step of the process is to oxidize isobutylene into methyl propenal, and the second step is to produce methyl propenol by using the hydrogen transfer method. Chinese patent CN103664526A discloses the technology in detail.

[0005] Compared with the above three methods, the selective hydrogenation is a more efficient and environmentally friendly method. Although some invention patents (CN102167657B, CN106631691A, CN107056566A) based on the method have been reported, the use of a large amount of solvent in the process, the use of a batch reactor, and the high cost of catalyst preparation highlight the problem, which causes certain obstacles to the actual industrial application. SUMMARY

[0006] In view of the deficiencies in the actual industrial application, the application induces selective hydrogenation reaction by innovating the structure design of the catalyst, and generally enhances the mass transfer capacity of the molecular sieve by post-processing. The catalyst is coupled with a continuous reactor, effectively improving the production capacity, using hydrogen as a reducing agent to realize the continuous production of 2-methylpropenol under the condition of no solvent.

[0007] The application takes the catalyst as the core, and realizes the better method by optimizing the design and preparation method of the catalyst.

[0008] The molecular sieve has the advantages of low cost, easy availability, stable structure and large specific surface area, and is widely used in petroleum chemical industry, gas separation and other fields.

[0009] The application relates to a molecular sieve loaded with Ag-MoO x The bimetallic catalyst has good activity, high selectivity and strong stability, and has great potential industrial application value.

[0010] According to one aspect of the application, an Ag-MoO x The preparation method of the bimetallic catalyst comprises:

[0011] (1) the molecular sieve and the alkali source are first immersed and treated, and then immersed with a solution containing a silver source and a molybdenum source, or the molecular sieve, the silver source and the molybdenum source are first immersed and treated, and then immersed with the alkali source, to obtain an immersion solution;

[0012] (2) the obtained immersion solution is dried and calcined to obtain the Ag-MoO x bimetallic catalyst.

[0013] Optionally, the alkali source is selected from at least one of sodium hydroxide, sodium bicarbonate and sodium carbonate.

[0014] Optionally, the mass ratio of the alkali source to the molecular sieve is 5:1-20:1.

[0015] Optionally, the concentration of the alkali source is 0.1-0.9M.

[0016] Optionally, the silver source is selected from at least one of silver nitrate, silver nitrite and silver acetate.

[0017] Optionally, the molybdenum source is selected from at least one of ammonium molybdate and molybdenum acetate.

[0018] Optionally, the molecular sieve is selected from at least one of Hbeta molecular sieve, ZSM-22 molecular sieve and ZSM-5 molecular sieve.

[0019] Optionally, the silicon-aluminum atomic ratio of the molecular sieve is 10-300.

[0020] Optionally, the molar ratio of the molecular sieve: base source: silver source: molybdenum source is: 1:10-1:10-1:10-1;

[0021] wherein the amount of the molecular sieve is in terms of its own molar amount, the amount of the base source is in terms of its own molar amount, the amount of the silver source is in terms of its own molar amount, and the amount of the molybdenum source is in terms of its own molar amount.

[0022] Optionally, the base source further comprises an auxiliary agent selected from the group consisting of triblock polymer F127 and / or cetyltrimethylammonium bromide.

[0023] Optionally, the mass ratio of the auxiliary agent to the base source is 100:1-1:100.

[0024] Optionally, the drying temperature is 25-150°C, and the drying time is 24-48h.

[0025] Optionally, the upper limit of the drying temperature is independently selected from the group consisting of 75°C, 100°C, 125°C, 150°C, and the lower limit is independently selected from the group consisting of 25°C, 50°C, 75°C, 100°C.

[0026] Optionally, the upper limit of the drying time is independently selected from the group consisting of 36h, 40h, 45h, 48h, and the lower limit is independently selected from the group consisting of 24h, 28h, 30h, 36h.

[0027] Optionally, the calcination temperature is 150-950°C, and the calcination time is 1-5h.

[0028] Optionally, the upper limit of the calcination temperature is independently selected from the group consisting of 400°C, 500°C, 800°C, 900°C, 950°C, and the lower limit is independently selected from the group consisting of 150°C, 200°C, 300°C, 400°C, 500°C.

[0029] Optionally, the upper limit of the calcination time is independently selected from the group consisting of 3h, 4h, 5h, and the lower limit is independently selected from the group consisting of 1h, 2h, 3h.

[0030] Optionally, the calcination atmosphere is at least one selected from the group consisting of a nitrogen atmosphere, an air atmosphere, and a carbon dioxide atmosphere.

[0031] According to another aspect of the present application, there is provided an Ag-MoO x The loading amount of the Ag and Mo metals in the bimetallic catalyst is 5-15wt.% of the mass of the Ag-MoO x The loading amount of the Ag and Mo metals in the bimetallic catalyst is 5-15wt.% of the mass of the Ag-MoO

[0032] Optionally, the Ag-MoO x The atomic ratio of the metal Ag to the metal Mo in the bimetallic catalyst is 1:1-20:1.

[0033] According to still another aspect of the present application, there is provided a method for preparing the Ag-MoO x The bimetallic catalyst, the Ag-MoO x The bimetallic catalyst is used in the selective hydrogenation of methylacrolein to prepare 2-methylallyl alcohol.

[0034] Optionally, the Ag-MoO x The bimetallic catalyst is used in the selective hydrogenation of methylacrolein to prepare 2-methylallyl alcohol.

[0035] Optionally, the reducing atmosphere is selected from at least one of hydrogen, carbon monoxide.

[0036] Optionally, the pre-reduction time is 2h-3h, and the pre-reduction temperature is 300-800°C.

[0037] Optionally, the pre-reduction time is selected from any value of 2h, 2.5h, 3h, or a range between any two of the above values.

[0038] Optionally, the upper limit of the pre-reduction temperature is independently selected from 500°C, 600°C, 700°C, 800°C, and the lower limit is independently selected from 300°C, 400°C, 500°C.

[0039] Optionally, the molar ratio of hydrogen to methylacrolein is 1:1-20:1.

[0040] Optionally, the mass space velocity of methylacrolein is 0.5-5h -1 .

[0041] Optionally, the reaction pressure is 0.1-5.0MPa, and the reaction temperature is 50-250°C.

[0042] Optionally, the upper limit of the molar ratio of hydrogen to methylacrolein is independently selected from 10:1, 15:1, 20:1, and the lower limit is independently selected from 1:1, 5:1, 7:1, 10:1.

[0043] Optionally, the upper limit of the mass space velocity of methylacrolein is independently selected from 2h -1 , 3h -1 , 4h -1 , 5h -1 , and the lower limit is independently selected from 0.5h -1 , 1h -1 , 2h -1 , 3h -1 .

[0044] As a specific embodiment, the present application is implemented by the following technical solutions:

[0045] The present application adopts the following scheme one:

[0046] (1) One or several of sodium hydroxide, sodium carbonate, sodium bicarbonate and ammonia are configured into an aqueous solution with a concentration of 0.1-0.9M.

[0047] (2) One kind of ZSM-5 molecular sieve with a silica-alumina ratio of 10-300 is added into the above solution, and the mass ratio of the solution to the molecular sieve is 5-20.

[0048] (3) The above solution is stirred vigorously, and the temperature is kept at 30-90℃ for 10-120min.

[0049] (4) The treated sample is centrifuged and washed for 7 times, and filtered.

[0050] (5) The filtered sample is dried at 25-150℃ for 24h.

[0051] (6) The sample is calcined in one or several of nitrogen, argon and air, the calcination temperature is 150-950℃, and the calcination time is 1-5h.

[0052] (7) Silver nitrate and ammonium molybdate are configured into an aqueous solution, and impregnated into the above sample, the loading amount of metal Ag is 5-15wt.%, and the atomic ratio of metal Ag to metal Mo in the catalyst is 20:1-1:1.

[0053] (8) The sample is dried at 25-150℃ for 24h.

[0054] (9) The sample is calcined in one or several of nitrogen, argon and air, the calcination temperature is 150-950℃, and the calcination time is 1-5h.

[0055] (10) The calcined catalyst is pressed, crushed into particles with a size of 20-40 mesh, and loaded into a fixed bed reactor, and the catalyst is reduced in situ using hydrogen at a temperature of 300-750℃.

[0056] (11) The reaction temperature is 50-250℃, the space velocity is 0.5-5h -1 , and the ratio of hydrogen to methylacrolein is 1-20.

[0057] The present application adopts the following scheme two:

[0058] (1) One or several of sodium hydroxide, sodium carbonate, sodium bicarbonate and ammonia are configured into an aqueous solution with a concentration of 0.1-0.9M, and 0.5g of CTAB and / or triblock polymer F127 is added.

[0059] (2) Add one of Hβ type molecular sieves with a silica-alumina ratio of 1-15 to the above solution, and the mass ratio of the solution to the molecular sieve is between 5-20.

[0060] (3) Stir the above solution vigorously, and keep the temperature between 30-90℃ for 10-120 min.

[0061] (4) Centrifuge and wash the treated sample for 7 times, and filter.

[0062] (5) Dry the filtered sample at 25-150℃ for 24 h.

[0063] (6) Calcine the sample in one or more of nitrogen, argon, and air, at a temperature of 150-950℃ for 1-5 h.

[0064] (7) Prepare an aqueous solution of silver nitrate and ammonium molybdate, and immerse the above sample in the solution, with a metal loading of 5-15 wt.%, and the atomic ratio of Ag to Mo in the catalyst is between 20:1 and 1:1.

[0065] (8) Dry the sample at 25-150℃ for 24 h.

[0066] (9) Calcine the sample in one or more of nitrogen, argon, and air, at a temperature of 150-950℃ for 1-5 h.

[0067] (10) Press the calcined catalyst into a tablet, crush it into particles of 20-40 mesh, and load it into a fixed bed reactor for in-situ reduction using hydrogen at a temperature of 300-750℃.

[0068] (11) The reaction temperature is between 50-250℃, the space velocity is between 0.5-5 h -1 , and the ratio of hydrogen to methylacrolein is between 1-20.

[0069] The third scheme adopted by the present application is:

[0070] (1) Prepare an aqueous solution with a concentration of 0.1-0.9 M using one or more of sodium hydroxide, sodium carbonate, sodium bicarbonate, and ammonia water, and add 0.5 g of CTAB and / or triblock polymer F127 to the solution.

[0071] (2) Add one of ZSM-5 molecular sieves with a silica-alumina ratio of 10-300 to the silver nitrate and ammonium molybdate solution, and the mass ratio of the solution to the molecular sieve is between 5-20, the mass of silver nitrate is added according to the loading of 5-15 wt.%, and the atomic ratio of Ag to Mo in the catalyst is between 20:1 and 1:1.

[0072] (3) Stir the above solution vigorously and keep the temperature between 30-90°C, and slowly add the base solution in (1) to it, and keep it for 10-120 min after the addition is complete.

[0073] (4) Centrifuge and wash the treated sample 7 times and filter it.

[0074] (5) Dry the filtered sample at 25-150°C for 24 h.

[0075] (6) Calcine the sample in one or more of nitrogen, argon, air, at a temperature between 150-950°C for a time between 1-5 h.

[0076] (7) Press the calcined catalyst, crush it to 20-40 mesh, and load it into a fixed bed reactor, and reduce the catalyst in situ using hydrogen at 300-750°C.

[0077] (8) The reaction temperature is between 50-250°C, the space velocity is between 0.5-5 h -1 , and the ratio of hydrogen to methylacrolein is between 1-20.

[0078] The fourth scheme adopted by the present application is:

[0079] (1) Use one or more of sodium hydroxide, sodium carbonate, sodium bicarbonate, and ammonia water to prepare an aqueous solution with a concentration of 0.1-0.9 M, and add 0.5 g of CTAB and / or triblock polymer F127 to it.

[0080] (2) Add silver nitrate and ammonium molybdate solution to one of the ZSM-22 molecular sieves with a silica-alumina ratio of 10-300, with a mass ratio of solution to molecular sieve of 5-20, and the mass of silver nitrate added according to the loading is between 5-15 wt.%, and the atomic ratio of metal Ag to metal Mo in the solution is between 20:1-1:1.

[0081] (3) Stir the above solution vigorously and keep the temperature between 30-90°C, and slowly add the base solution in (1) to it, and keep it for 10-120 min after the addition is complete.

[0082] (4) Centrifuge and wash the treated sample 7 times and filter it.

[0083] (5) Dry the filtered sample at 25-150°C for 24 h.

[0084] (6) Calcine the sample in one or more of nitrogen, argon, air, at a temperature between 150-950°C for a time between 1-5 h.

[0085] (7) The calcined catalyst is pressed into a tablet, crushed into particles of 20-40 mesh, and loaded into a fixed bed reactor for in-situ reduction at 300-750°C using hydrogen.

[0086] (8) The reaction temperature is between 50-250°C, the space velocity is between 0.5-5h -1 , and the ratio of hydrogen to methylacrolein is between 1-20.

[0087] The beneficial effects that can be produced by the present application include:

[0088] The present application has relatively low preparation cost, high reaction activity, high selectivity of target product, and strong stability, relative to noble metal Pt, Pd, Ir catalysts, and molecular sieve loaded Ag and Mo catalysts; a continuous reactor is used for production, and the reaction is carried out under solvent-free, relatively mild reaction conditions; the heterogeneous catalyst facilitates separation from the product, and effective improvement of the mass transfer capacity of the catalytic system through post-treatment of the molecular sieve makes the reaction more easily carried out; under the conditions of hydrogen as a reducing agent and solvent-free, the conversion rate of methylacrolein on the bimetallic catalyst reaches 82%, the selectivity of 2-methylallyl alcohol is 89%, and the catalyst can be stably operated for a relatively long time. BRIEF DESCRIPTION OF DRAWINGS

[0089] Figure 1 H2-TPR graph in Example 1 of the present application.

[0090] Figure 2 H2-TPR graph in Example 2 of the present application. DETAILED DESCRIPTION

[0091] The present application will be described in detail below with reference to examples, but the present application is not limited to these examples.

[0092] Unless otherwise specified, the raw materials in the examples of the present application are purchased through commercial channels.

[0093] Conversion rate = 1 - amount of unconverted reactant / total amount of reactant.

[0094] Selectivity = amount of generated product / amount of converted reactant.

[0095] The present application uses a Mac autochemisoption 2 instrument to characterize the catalyst.

[0096] Example 1

[0097] Take 10 g NaOH, 0.5 g cetyltrimethylammonium bromide (CTAB) and 100 ml water, mix them to form a solution and put them into a bottle made of polytetrafluoroethylene. Put the solution into a water bath and keep the temperature at 80°C. Take 10 g Hβ zeolite with a Si / Al atomic ratio of 10 and add it into the solution, keep it for 40 min, then centrifuge and wash the sample 7 times. Put the filtered sample into an oven at 100°C and dry it for 24 h. Then put the dried sample into a nitrogen atmosphere and calcine it at 600°C for 5 h. Take 1 g silver nitrate and 0.1 g ammonium molybdate and dissolve them in 4 ml deionized water. Take 3 g of the treated zeolite sample and immerse the metal salt solution into the zeolite. Keep it at 25°C for 24 h, then dry it at 120°C for 24 h and finally calcine it at 500°C for 5 h. Crush the calcined catalyst into particles with a size of 20-40 mesh, put it into a fixed bed reactor and reduce it in situ with hydrogen at 750°C. When the fixed bed reactor cools down to 180°C, pass in methylpropylal at a space velocity of 2 h -1 , where the ratio of hydrogen to methylpropylal is 10, and the selectivity of methylpropylal and isobutyral is shown in Table 1. The results of the characterization of the calcined catalyst are shown in Table 2, and it can be seen from Table 2 that the reduction temperature of the metal Ag lags behind and the metal grain size is large. Figure 1 Figure 1 It can be seen from Table 2 that the reduction temperature of the metal Ag is low and the dispersion degree is high.

[0098] Example 2

[0099] Take 10 g NaOH, 0.5 g cetyltrimethylammonium bromide (CTAB) and 100 ml water, mix them to form a solution and put them into a bottle made of polytetrafluoroethylene. Put the solution into a water bath and keep the temperature at 80°C. Take 10 g Hβ zeolite with a Si / Al atomic ratio of 10 and add it into the solution, keep it for 40 min, then centrifuge and wash the sample 7 times. Put the filtered sample into an oven at 100°C and dry it for 24 h. Then put the dried sample into a nitrogen atmosphere and calcine it at 600°C for 5 h. Take 1 g silver nitrate and 0.1 g ammonium molybdate and dissolve them in 4 ml deionized water. Take 3 g of the treated zeolite sample and immerse the metal salt solution into the zeolite. Keep it at 25°C for 24 h, then dry it at 120°C for 24 h and finally calcine it at 500°C for 5 h. Crush the calcined catalyst into particles with a size of 20-40 mesh, put it into a fixed bed reactor and reduce it in situ with hydrogen at 750°C. When the fixed bed reactor cools down to 180°C, pass in methylpropylal at a space velocity of 2 h -1 , where the ratio of hydrogen to methylpropylal is 10, and the selectivity of methylpropylal and isobutyral is shown in Table 1. Figure 2 It can be seen from Table 2 that the reduction temperature of the metal Ag is low and the dispersion degree is high.

[0100] Example 3

[0101] ​Dissolve 4g sodium carbonate, 6g sodium hydroxide, and 0.5g F127 in 100ml of water to prepare solution A. Add 10g of ZSM-5 molecular sieve with a silicon-to-aluminum ratio of 30, 1g silver nitrate, and 0.1g ammonium molybdate to a polytetrafluoroethylene bottle containing 100ml of water and maintain a constant temperature of 60℃. Slowly add solution A to the molecular sieve suspension using a constant flow pump and maintain the temperature for 60min. Centrifuge and wash the treated sample seven times and filter. Dry the filtered sample at 120℃ for 24h. Finally, calcine at 500℃ for 5h. Press the calcined catalyst into tablets, crush them to 20-40 mesh, and load them into a fixed-bed reactor. Reduce the catalyst in situ using hydrogen at 750℃. After the fixed-bed reactor cools to 180℃, purge with methacrolein at a space velocity of 2h. -1 The ratio of hydrogen to methacrolein is 10, and the selectivity of methacrolein and isobutyraldehyde is shown in Table 1.

[0102] Example 4

[0103] Dissolve 4g sodium carbonate, 6g sodium hydroxide, and 0.5g F127 in 100ml of water to prepare solution A. Add 10g of ZSM-22 molecular sieve with a silicon-to-aluminum ratio of 30, 1g silver nitrate, and 0.1g ammonium molybdate to a polytetrafluoroethylene bottle containing 100ml of water and maintain a constant temperature of 60℃. Slowly add solution A to the molecular sieve suspension using a constant flow pump and maintain the temperature for 60min. Centrifuge and wash the treated sample seven times and filter. Dry the filtered sample at 120℃ for 24h. Finally, calcine at 500℃ for 5h. Press the calcined catalyst into tablets, crush them to 20-40 mesh, and load them into a fixed-bed reactor. Reduce the catalyst in situ using hydrogen at 750℃. After the fixed-bed reactor cools to 180℃, purge with methacrolein at a space velocity of 2h. -1 The ratio of hydrogen to methacrolein is 10, and the selectivity of methacrolein and isobutyraldehyde is shown in Table 1.

[0104] Comparative Example

[0105] Dissolve 1g of silver nitrate in 4ml of deionized water. Weigh 3g of untreated ZSM-5 molecular sieve (silicon-to-aluminum atomic ratio 30) sample and impregnate the molecular sieve with silver nitrate and ammonium molybdate solution. Let stand at 25℃ for 24h, then dry at 120℃ for 24h, and finally calcine at 500℃ for 5h. Compress and crush the calcined catalyst into 20-40 mesh particles, and load them into a fixed-bed reactor. Reduce the catalyst in situ using hydrogen at 750℃. After the fixed-bed reactor cools to 180℃, purge with methacrolein at a space velocity of 2h. -1 The ratio of hydrogen to methacrolein is 10, and the selectivity of methacrolein and isobutyraldehyde is shown in Table 1.

[0106] Table 1 Activity evaluation results in the examples

[0107]

[0108]

[0109] From Table 1 it can be seen that Example 3 shows good activity and selectivity to the target product in the particular preparation method described.

[0110] The above is only a few embodiments of the present application, not any form of the present application to limit, although the preferred embodiments disclosed as above, however, not to limit the present application, any skilled in the art, without departing from the scope of the present application, using the above disclosed technical content to make some changes or modifications are equivalent to equivalent embodiments, are within the scope of the technical solutions.

Claims

1. A method for selectively hydrogenating methacrolein to prepare 2-methylpropenol, characterized in that, The Ag-MoO x After the bimetallic catalyst is pre-reduced under a reducing atmosphere, it is then contacted with methacrolein and hydrogen to react and generate 2-methylpropenol. The loading of Ag and Mo metals is that of Ag-MoO x 5-15 wt% of the bimetallic catalyst; The Ag-MoO x The preparation of bimetallic catalysts includes the following steps: (1) After impregnating the molecular sieve and the alkali source, the molecular sieve and the alkali source are impregnated with a solution containing silver source and molybdenum source; (2) The obtained impregnation solution is dried and calcined to obtain the Ag-MoO. x Bimetallic catalysts; The molecular sieve is selected from at least one of Hβ type molecular sieve, ZSM-22 molecular sieve, and ZSM-5 molecular sieve; The molar ratio of the molecular sieve, alkali source, silver source, and molybdenum source is 1:10~1:10~1:10~1; Wherein, the amount of the molecular sieve is measured in its own molar quantity, the amount of the alkali source is measured in its own molar quantity, the amount of the silver source is measured in its own molar quantity, and the amount of the molybdenum source is measured in its own molar quantity. The alkali source also includes an auxiliary agent selected from triblock polymer F127 and / or hexadecyltrimethylammonium bromide.

2. The method according to claim 1, characterized in that, The alkali source is selected from at least one of sodium hydroxide, sodium bicarbonate, and sodium carbonate. The mass ratio of the alkali source to the molecular sieve is 5:1 to 20:1; The concentration of the alkali source is 0.1~0.9M.

3. The method according to claim 1, characterized in that, The silver source is selected from at least one of silver nitrate, silver nitrite, and silver acetate; The molybdenum source is selected from at least one of ammonium molybdate and molybdenum acetate; The molecular sieve has a silicon-to-aluminum atomic ratio of 10 to 300.

4. The method according to claim 1, characterized in that, The mass ratio of the auxiliary agent to the alkali source is 100:1 to 1:

100.

5. The method according to claim 1, characterized in that, The drying temperature is 25~150 ℃, and the drying time is 24~48 h; The calcination temperature is 150~950 ℃, and the calcination time is 1~5 h; The roasting atmosphere is selected from at least one of nitrogen atmosphere, air atmosphere, and carbon dioxide atmosphere.

6. The method according to claim 1, characterized in that, The Ag-MoO x In bimetallic catalysts, the atomic ratio of Ag to Mo is 1:1 to 20:

1.

7. The method according to claim 1, characterized in that, The Ag-MoO x After the bimetallic catalyst is pre-reduced under a reducing atmosphere, it is then contacted with methacrolein and hydrogen to react and generate 2-methylpropenol. The reducing atmosphere is selected from at least one of hydrogen and carbon monoxide; The pre-reduction time is 2 h to 3 h, and the pre-reduction temperature is 300 to 800 ℃.

8. The method according to claim 1, characterized in that, The molar ratio of hydrogen to methacrolein is 1:1 to 20:1; The mass hourly space velocity (MSV) of the methacrolein is 0.5–5 h⁻¹. -1 ; The reaction pressure is 0.1~5.0 MPa, and the reaction temperature is 50~250 ℃.

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