Preparation method of methanol synthesis catalyst by precipitation method and methanol synthesis catalyst

Abstract

The invention relates to a preparation method of a methanol synthesis catalyst by a precipitation method and the methanol synthesis catalyst, and relates to the technical field of catalysts, the preparation method comprises the following steps: preparing a mixed solution containing Cu < 2 + >, Zn < 2 + > and Al < 3 + >; dropwise adding a precipitant solution into the mixed solution, and controlling the reaction temperature to be maintained at 60-70 DEG C and the pH value of a reaction system to be 7.5-8.5; after dropwise adding, continuously stirring and reacting to obtain a reaction mixture; and aging the reaction mixture, filtering, washing and drying the obtained precipitate, and the like. The preparation process of the catalyst is simple, the prepared catalyst is used for methanol synthesis reaction and shows excellent catalytic performance, the initial activity reaches 1.38 g / (mL.h), the activity after heat resistance reaches 1.23 g / (mL.h), and remarkable economic benefits and social benefits can be generated.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts, and in particular to a preparation method of a methanol synthesis catalyst using a precipitation method and the methanol synthesis catalyst. Background Art

[0002] Methanol, as an important chemical raw material and clean energy carrier, plays a crucial role in industrial production. The performance of methanol synthesis catalysts plays a key role in the efficiency, quality, and cost of methanol production. Conventional methanol synthesis catalysts have limitations in activity, selectivity, and stability, failing to meet the growing industrial demand. Therefore, developing a method for preparing high-performance methanol synthesis catalysts is of great practical significance.

[0003] Currently, the main preparation methods for methanol synthesis catalysts include precipitation, impregnation, combined coprecipitation-impregnation, and solution-gel methods. The precipitation method regulates the catalyst's microstructure and performance by controlling precipitation conditions (such as temperature, pH, and type of precipitant). Highly active methanol synthesis catalysts are typically prepared using copper nitrate, zinc nitrate, or aluminum nitrate as raw materials and sodium bicarbonate as a precipitant. The advantages of the precipitation method are its relative simplicity, low cost, and ability to better control the catalyst's composition and particle size distribution. The impregnation method typically involves immersing a support in a solution containing the active component, loading the active component onto the support to produce a highly efficient methanol synthesis catalyst. The advantages of the impregnation method are its ability to precisely control the loading of the active component and its simplicity. The combined coprecipitation-impregnation method first prepares the catalyst precursor via coprecipitation, followed by the introduction of additives or further modification of the catalyst's performance via impregnation. This method combines the advantages of both methods, resulting in the preparation of catalysts with superior performance. The sol-gel method forms a sol through the hydrolysis and condensation reaction of metal alkoxides, and then prepares the catalyst through steps such as gelation, drying and calcination. This method can prepare catalysts with high specific surface area and uniform dispersion, but the process is relatively complex and the cost is high.

[0004] Many methanol synthesis reactions require higher temperatures to achieve a considerable reaction rate, but high temperature conditions may lead to an increase in side reactions, reduce methanol selectivity, and also affect the service life of the catalyst. Therefore, the development of catalysts with high activity, especially high activity at low temperatures, is one of the key challenges. This can achieve efficient methanol synthesis at lower temperatures, reduce the occurrence of side reactions, and improve energy efficiency and product selectivity. Methanol synthesis reactions are usually carried out at higher temperatures and pressures, which makes the catalyst prone to sintering, resulting in a decrease in the specific surface area of the catalyst and a decrease in active sites, thereby reducing the activity and selectivity of the catalyst. In addition, high temperatures may also cause phase changes in the catalyst, change the crystal structure and surface properties of the catalyst, and further affect its catalytic performance. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides a method for preparing a methanol synthesis catalyst by a precipitation process and a methanol synthesis catalyst.

[0006] In a first aspect, the present invention provides a method for preparing a catalyst for methanol synthesis by precipitation, such as Figure 1 As shown, the preparation method comprises the following steps:

[0007] Formulated with Cu 2+ 、Zn 2+ 、Al 3+ A mixed solution;

[0008] Adding a precipitant solution dropwise to the mixed solution, controlling the reaction temperature to maintain at 60-70° C. and the pH value of the reaction system to maintain at 7.5-8.5; continuing to stir the reaction after the addition is complete to obtain a reaction mixture;

[0009] The reaction mixture is aged and then filtered, and the resulting precipitate is washed and dried, and then roasted, mixed with auxiliary powder, ground, granulated and tableted to obtain the catalyst; or,

[0010] The reaction mixture is aged, and then an auxiliary agent solution is added and stirred. The obtained precipitate is washed and dried, and then calcined, granulated and tableted to obtain the catalyst.

[0011] Furthermore, the Cu 2+ 、Zn 2+ 、Al 3+ The molar ratio is (2~6):(2~4.5):(1~3).

[0012] Furthermore, the total concentration of metal ions in the mixed solution is 1.0 mol / L.

[0013] Furthermore, the preparation contains Cu 2+ 、Zn 2+ 、Al 3+ The steps of mixing the solution include the following process:

[0014] Copper nitrate, zinc nitrate and aluminum nitrate were weighed separately, and dissolved in an appropriate amount of deionized water to prepare the mixed solution.

[0015] Furthermore, the precipitant solution includes at least one of a sodium bicarbonate precipitant solution, a sodium carbonate precipitant solution and an ammonia precipitant solution.

[0016] Furthermore, the preparation of the sodium bicarbonate precipitant solution includes the following process: weighing 168 g of sodium bicarbonate and dissolving it in 1000 mL of deionized water to prepare a sodium bicarbonate solution with a concentration of 2.0 mol / L;

[0017] The preparation of the sodium carbonate precipitant solution includes the following steps: weighing 106 g of sodium carbonate and dissolving it in 1000 mL of deionized water to prepare a sodium carbonate solution with a concentration of 1.0 mol / L;

[0018] The preparation of the ammonia precipitant solution includes the following steps: measuring 700 mL of concentrated ammonia with a mass fraction of 25%, diluting it to 1000 mL with deionized water, and preparing an ammonia solution with a concentration of 2.0 mol / L.

[0019] Furthermore, the additives include silicon oxide, magnesium oxide, zirconium oxide and manganese oxide; the silicon oxide is added in an amount of 2%-4% of the total mass of the catalyst, the magnesium oxide is added in an amount of 1%-3% of the total mass of the catalyst, the zirconium oxide is added in an amount of 1%-3% of the total mass of the catalyst, and the manganese oxide is added in an amount of 2%-4% of the total mass of the catalyst.

[0020] Furthermore, the auxiliary agent can be added in the form of powder by mixing and grinding and then directly added, or in the form of auxiliary agent solution.

[0021] In a second aspect, the present invention provides a methanol synthesis catalyst, which is prepared by the preparation method of the methanol synthesis catalyst by the precipitation method described in any one of the first aspects.

[0022] The above technical solution provided by the embodiment of the present invention has at least the following advantages compared with the prior art:

[0023] The present invention provides a method for preparing a methanol synthesis catalyst using a precipitation process and a methanol synthesis catalyst. Compared with the prior art, the catalyst preparation process of the present invention is simple. The catalyst prepared exhibits excellent catalytic performance for methanol synthesis reactions, with an initial activity of 1.38 g / (mL·h) and a heat-resistant activity of 1.23 g / (mL·h), which can generate significant economic and social benefits. Specifically:

[0024] (1) The active ingredients are more evenly dispersed;

[0025] (2) The carrier has better thermal conductivity and heat can be removed in time;

[0026] (3) Adding metal additives can effectively promote the synergistic effect of metal carriers, inhibit the sintering and agglomeration of active components during the reaction process, and enhance the stability of the catalyst. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0029] Figure 1 The present invention provides a flow chart of a method for preparing a methanol synthesis catalyst by a precipitation method. DETAILED DESCRIPTION

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0031] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0032] The technical solutions provided by the present invention are as follows:

[0033] The purpose of the present invention is to provide a method for preparing a methanol synthesis catalyst by a precipitation process, wherein a methanol synthesis catalyst with high activity, high selectivity and good stability is prepared by optimizing the raw material ratio, the selection of the precipitant, and the addition form and content of the auxiliary agent.

[0034] Preparation of mixed solution

[0035] Weigh a certain amount of copper nitrate [Cu(NO3)2·3H2O], zinc nitrate [Zn(NO3)2·6H2O] and aluminum nitrate [Al(NO3)3·9H2O], dissolve them in appropriate amount of deionized water to prepare a mixed solution, in which Cu 2+ 、Zn 2+ 、Al 3+ The molar ratio is (2-6):(2-4.5):(1-3), and the total concentration of metal ions in the mixed solution is 1.0 mol / L.

[0036] Preparation of precipitant solution

[0037] (1) Sodium bicarbonate precipitant solution: Weigh 168 g of sodium bicarbonate (NaHCO3) and dissolve it in 1000 mL of deionized water to prepare a sodium bicarbonate solution with a concentration of 2.0 mol / L.

[0038] (2) Sodium carbonate precipitant solution: Weigh 106 g of sodium carbonate (Na2CO3) and dissolve it in 1000 mL of deionized water to prepare a sodium carbonate solution with a concentration of 1.0 mol / L.

[0039] (3) Ammonia precipitant solution: Measure 700 mL of 25% concentrated ammonia water and dilute it to 1000 mL with deionized water to prepare an ammonia solution with a concentration of 2.0 mol / L.

[0040] Preparation of additives

[0041] (1) Silica additive:

[0042] Direct addition form: Prepare nano-silica powder with a particle size of 30-50nm.

[0043] Solution addition form: prepare silica sol with a silica content of 30% (mass fraction).

[0044] (2) Magnesium oxide additive:

[0045] Direct addition form: Prepare light magnesium oxide powder with a purity of 99%.

[0046] Solution addition method: Weigh 128.2 g of magnesium nitrate [Mg(NO3)2·6H2O], dissolve it in an appropriate amount of deionized water, and dilute the volume to 1000 mL to prepare a magnesium nitrate solution with a concentration of 0.5 mol / L.

[0047] (3) Zirconia additives:

[0048] Direct addition form: Prepare manganese dioxide powder with a purity of 99%.

[0049] Solution addition method: Weigh 214.7 g of zirconium nitrate [Zr(NO3)4·5H2O], dissolve it in an appropriate amount of deionized water, and dilute the volume to 1000 mL to prepare a zirconium nitrate solution with a concentration of 0.5 mol / L.

[0050] (4) Manganese oxide additive:

[0051] Direct addition form: Prepare manganese dioxide powder with a purity of 98%.

[0052] Solution addition method: Weigh 143.5 g of manganese nitrate [Mn(NO3)2·6H2O], dissolve it in an appropriate amount of deionized water, and dilute to 1000 mL to prepare a manganese nitrate solution with a concentration of 0.5 mol / L.

[0053] Catalyst preparation steps

[0054] (1) Prepare a mixed solution of copper nitrate, zinc nitrate and aluminum nitrate, where Cu 2+、Zn 2+ 、Al 3+ The molar ratio is (2-6):(2-4.5):(1-3), and the total metal ion concentration is 1.0 mol / L;

[0055] (2) selecting one of sodium bicarbonate, sodium carbonate, and ammonia water as a precipitant, and preparing precipitant solutions with concentrations of 2.0 mol / L, 1.0 mol / L, and 2.0 mol / L, respectively;

[0056] (3) Under stirring conditions, the precipitant solution was added dropwise to the mixed solution at a rate of 3-5 mL / min, the reaction temperature was controlled at 60-70°C, the pH value was between 7.5-8.5, and the reaction was stirred for 1.5 hours;

[0057] (4) The reaction mixture was aged at 80°C for 2 hours, then filtered and washed until there was no NO3 in the washing liquid. - , dried at 120°C for 12 hours, and calcined at 450°C for 4 hours to obtain a catalyst precursor;

[0058] (5) adding silicon oxide, magnesium oxide, zirconium oxide or manganese oxide additives to the aged mixture or catalyst precursor in the form of direct powder addition or solution impregnation, wherein the amount of silicon oxide added is 2%-4% of the total mass of the catalyst, the amount of magnesium oxide added is 1%-3%, the amount of zirconium oxide added is 1%-3%, and the amount of manganese oxide added is 2%-4%;

[0059] (6) If direct addition is adopted, the auxiliary agent powder and the catalyst precursor are fully ground and mixed; if solution impregnation is adopted, the catalyst precursor is immersed in the auxiliary agent solution, stirred and impregnated at 60°C for 3 hours, filtered, dried at 120°C for 6 hours, and calcined at 400°C for 2 hours.

[0060] The silicon oxide additive is directly added in the form of nano-silicon dioxide powder with a particle size of 30-50nm, and the solution addition form is a silica sol with a silicon dioxide content of 30% (mass fraction); the magnesium oxide additive is directly added in the form of light magnesium oxide powder with a purity of 99%, and the solution addition form is a magnesium nitrate solution with a concentration of 0.5mol / L; the zirconium oxide additive is directly added in the form of zirconium oxide powder with a purity of 99%, and the solution addition form is a zirconium nitrate solution with a concentration of 0.5mol / L; the manganese oxide additive is directly added in the form of manganese dioxide powder with a purity of 98%, and the solution addition form is a manganese nitrate solution with a concentration of 0.5mol / L.

[0061] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are intended to illustrate the present invention only and are not intended to limit the scope of the invention. The experimental methods in the following examples where specific conditions are not specified are generally measured in accordance with national standards. If there are no corresponding national standards, then the methods are carried out in accordance with general international standards, conventional conditions, or the conditions recommended by the manufacturer.

[0062] Example 1

[0063] (1) Prepare a mixed solution, wherein Cu 2+ 、Zn 2+ 、Al 3+ The molar ratio is 2.5:4.5:3.

[0064] (2) Precipitant: sodium bicarbonate.

[0065] (3) Additives: None.

[0066] While stirring, a sodium bicarbonate precipitant solution was added dropwise to the mixed solution at a rate of 5 mL / min. The reaction temperature was controlled at 65°C and the pH was 8.0. The precipitation reaction and subsequent aging, filtration, washing, drying, calcination, granulation, and tableting steps were completed to obtain catalyst sample C1.

[0067] Example 2

[0068] (1) Prepare a mixed solution, wherein Cu 2+ 、Zn 2+ 、Al 3+ The molar ratio is 3:4:3.

[0069] (2) Precipitant: sodium bicarbonate.

[0070] (3) Auxiliary agent: silicon oxide (directly added).

[0071] After the catalyst precursor was prepared, nano-silicon dioxide powder accounting for 2% of the total mass of the catalyst was directly added thereto, fully ground and mixed, and calcined again (400° C., 2 hours). Catalyst sample C2 was obtained through granulation and tableting.

[0072] Example 3

[0073] (1) Prepare a mixed solution, wherein Cu 2+ 、Zn 2+ 、Al 3+ The molar ratio is 4:3:3.

[0074] (2) Precipitant: sodium bicarbonate.

[0075] (3) Auxiliary agent: silicon oxide (added in solution).

[0076] Silica sol was added to the aged mixture, and the mixture was operated so that the silicon oxide content in the final catalyst was 4%. After completion, the mixture was filtered, dried, calcined, granulated and tableted to obtain catalyst sample C3.

[0077] Example 4

[0078] (1) Prepare a mixed solution, wherein Cu 2+ 、Zn 2+ 、Al 3+ The molar ratio is 5:3:2.

[0079] (2) Precipitant: sodium carbonate.

[0080] (3) Additives: None.

[0081] The sodium carbonate precipitant solution was added dropwise to the mixed solution at a rate of 3 mL / min, and the reaction temperature was controlled at 62° C. and the pH value was 7.8. After completing the conventional preparation steps, catalyst sample C4 was obtained.

[0082] Example 5

[0083] (1) Prepare a mixed solution, wherein Cu 2+ 、Zn 2+ 、Al 3+ The molar ratio is 6:3:1.

[0084] (2) Precipitant: sodium carbonate.

[0085] (3) Auxiliary agent: magnesium oxide (directly added).

[0086] After the catalyst precursor was prepared, light magnesium oxide powder accounting for 3% of the total mass of the catalyst was directly added thereto, ground and mixed, and then calcined again (400° C., 2 hours), granulated and tableted to obtain catalyst sample C5.

[0087] Example 6

[0088] (1) Prepare a mixed solution, wherein Cu 2+ 、Zn 2+ 、Al 3+ The molar ratio is 4:4:2.

[0089] (2) Precipitant: sodium carbonate.

[0090] (3) Auxiliary agent: magnesium oxide (added in solution).

[0091] A magnesium nitrate solution was added to the aged mixture to adjust the magnesium oxide content in the final catalyst to 5%. The mixture was then filtered, dried, calcined, granulated and tableted to obtain catalyst sample C6.

[0092] Example 7

[0093] (1) Prepare a mixed solution, wherein Cu 2+ 、Zn 2+ 、Al 3+ The molar ratio is 3:4.5:2.5.

[0094] (2) Precipitant: ammonia water.

[0095] (3) Additive: manganese oxide (directly added).

[0096] While stirring, aqueous ammonia solution was added dropwise to the mixed solution at a rate of 4 mL / min. The reaction temperature was controlled at 68°C and the pH was 8.2. After obtaining the catalyst precursor, manganese dioxide powder (4% by weight of the total catalyst) was directly added. After mixing thoroughly, the mixture was calcined (400°C for 2 hours), granulated, and tableted to obtain Catalyst Sample C7.

[0097] Example 8

[0098] (1) Prepare a mixed solution, wherein Cu 2+ 、Zn 2+ 、Al 3+ The molar ratio is 6:2:2.

[0099] (2) Precipitant: ammonia water.

[0100] (3) Additives: silicon oxide (added in solution), magnesium oxide (added directly), and manganese oxide (added in solution).

[0101] First, silica sol was added to the aged mixture to achieve a silica content of 3%. Then, light magnesium oxide powder, accounting for 2% of the total catalyst mass, was directly added. Zirconium nitrate solution was then added to achieve a zirconium oxide content of 2%. Finally, manganese nitrate solution was added to achieve a manganese oxide content of 3%. After completing each step, catalyst sample C8 was obtained.

[0102] Test Case

[0103] Activity testing: A micro-fixed-bed continuous flow reactor was used with a catalyst loading of 2 mL and a particle size of 16-40 mesh. The catalyst was reduced in a low-hydrogen atmosphere (H₂:N₂ = 5:95) at a programmed temperature (20°C / h) for 10 hours to 230°C. The reducing gas was switched to the feed gas for activity testing.

[0104] The activity test conditions are reaction pressure 8.0MP, space velocity 10000h -1The catalyst was heat-treated at 350°C for 20 hours at a temperature of 230°C and a syngas composition of H₂:CO:CO₂:N₂ = 65:14:4:17 (v / v). The post-heat-resistant activity of the catalyst was measured under the above conditions. The activity value is expressed as the space-time yield of methanol produced (g / (mL·h)). The ratio of the post-heat-resistant activity to the initial activity was used to compare the thermal stability of the samples. Specific data are shown in Table 1 below.

[0105] Table 1

[0106]

[0107]

[0108] The data in the table show that the addition of additives significantly improves both the initial and post-heat-resistant activities of the catalysts. The different methods and amounts of precipitants and additives significantly influence catalyst performance. Sample C8 exhibits the best catalytic performance, achieving an initial activity of 1.38 g / (mL·h) and a post-heat-resistant activity of 1.23 g / (mL·h), thanks to the synergistic effect of multiple additives.

[0109] Various embodiments of the present invention may be presented in the form of a range; it should be understood that the description in a range format is only for convenience and brevity and should not be construed as an inflexible limitation on the scope of the invention; therefore, the range description should be considered to have specifically disclosed all possible subranges and single numerical values within the range. For example, the description of a range from 1 to 6 should be considered to have specifically disclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. In addition, whenever a numerical range is indicated herein, it is intended to include any cited numeral (fractional or integer) within the indicated range.

[0110] The foregoing description is intended only to provide specific embodiments of the present invention, which will enable those skilled in the art to understand and implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not intended to be limited to the embodiments shown herein, but is intended to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for preparing a methanol synthesis catalyst by a precipitation process, characterized in that: The preparation method comprises the following steps: Formulated with Cu 2+ 、Zn 2+ 、Al 3+ a mixed solution; Adding a precipitant solution dropwise to the mixed solution, controlling the reaction temperature to maintain at 60-70° C. and the pH value of the reaction system to maintain at 7.5-8.5; continuing to stir the reaction after the addition is complete to obtain a reaction mixture; The reaction mixture is aged and then filtered, and the resulting precipitate is washed and dried, and then roasted, mixed with auxiliary powder, ground, granulated and tableted to obtain the catalyst; or, The reaction mixture is aged, and then an auxiliary agent solution is added and stirred. The obtained precipitate is washed and dried, and then calcined, granulated and tableted to obtain the catalyst.

2. The method for preparing a catalyst for methanol synthesis by precipitation according to claim 1, wherein The molar ratio of Cu2+, Zn2+ and Al3+ in the mixed solution is (2-6):(2-4.5):(1-3).

3. The method for preparing a methanol synthesis catalyst by precipitation method according to claim 1, characterized in that: The total concentration of metal ions in the mixed solution is 1.0 mol / L.

4. The method for preparing a catalyst for methanol synthesis by precipitation according to claim 1, wherein: Formulated with Cu 2 + 、Zn 2+ 、Al 3+ The steps of mixing the solution include the following process: Copper nitrate, zinc nitrate and aluminum nitrate were weighed separately, and dissolved in an appropriate amount of deionized water to prepare the mixed solution.

5. The method for preparing a catalyst for methanol synthesis by precipitation according to claim 1, wherein: The precipitant solution includes at least one of a sodium bicarbonate precipitant solution, a sodium carbonate precipitant solution and an ammonia precipitant solution.

6. The method for preparing a catalyst for methanol synthesis by precipitation according to claim 1, wherein: The preparation of the sodium bicarbonate precipitant solution includes the following steps: weighing 168 g of sodium bicarbonate and dissolving it in 1000 mL of deionized water to prepare a sodium bicarbonate solution with a concentration of 2.0 mol / L; The preparation of the sodium carbonate precipitant solution includes the following steps: weighing 106 g of sodium carbonate and dissolving it in 1000 mL of deionized water to prepare a sodium carbonate solution with a concentration of 1.0 mol / L; The preparation of the ammonia precipitant solution includes the following steps: measuring 700 mL of concentrated ammonia with a mass fraction of 25%, diluting it to 1000 mL with deionized water, and preparing an ammonia solution with a concentration of 2.0 mol / L.

7. The method for preparing a catalyst for methanol synthesis by precipitation according to claim 1, wherein: The additives include silicon oxide, magnesium oxide, zirconium oxide and manganese oxide; the silicon oxide is added in an amount of 2% to 4% of the total mass of the catalyst, the magnesium oxide is added in an amount of 1% to 3% of the total mass of the catalyst, the zirconium oxide is added in an amount of 1% to 3% of the total mass of the catalyst, and the manganese oxide is added in an amount of 2% to 4% of the total mass of the catalyst.

8. The method for preparing a catalyst for methanol synthesis by precipitation according to claim 7, characterized in that: The auxiliary agent can be added in the form of powder by mixing and grinding and then directly added, or in the form of auxiliary agent solution.

9. A methanol synthesis catalyst, characterized in that: The methanol synthesis catalyst is prepared by the preparation method of the methanol synthesis catalyst by precipitation method according to any one of claims 1 to 8.

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