Hydrophobic copper bismuth catalyst and preparation method thereof

Abstract

The invention belongs to the technical field of catalysts, and particularly relates to a hydrophobic copper bismuth catalyst and a preparation method thereof. The method comprises the following steps: carrying out coprecipitation on active components to obtain a precursor 1, (2) carrying out hydrophobic modification on the precursor 1 to obtain an intermediate 2, and (3) carrying out spray drying on the intermediate 2 to obtain the catalyst. The copper-bismuth catalyst is a carrier-free catalyst, after the surface of the copper-bismuth catalyst is subjected to hydrophobic modification, enrichment of raw materials acetylene and formaldehyde on the surface of the catalyst can be promoted, the reaction rate is increased, diffusion of a hydrophilic reaction product 1, 4-butynediol to a water phase is facilitated, and generation of side reaction polyacetylene is inhibited. The catalyst has the characteristics of high activity, high selectivity and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of catalysts, and in particular relates to a hydrophobic copper-bismuth catalyst and a preparation method thereof. Background Art

[0002] 1,4-Butynediol (BYD), a colorless or slightly yellow flaky crystal, is an important chemical organic product. It is mainly used to produce tetrahydrofuran, butylene terephthalate, γ-butyrolactone, polyurethane resin, polybutylene terephthalate-adipate-butylene terephthalate, coatings and plasticizers, etc. It has a wide range of uses and a large demand. There are three industrial production process routes for BYD, the acetylene aldehyde method, the maleic anhydride method and the bioconversion method. Among them, the acetylene aldehyde method using formaldehyde and acetylene as raw materials is the most widely used.

[0003] Copper bismuth catalyst is a commonly used catalyst in the acetylene aldehyde method, which can be divided into unsupported copper bismuth catalyst and supported copper bismuth catalyst. Patents CN106669697B, CN106669698B and CN108067239B disclose a variety of unsupported catalysts. Researchers mainly regulate the catalyst particle size and particle size distribution by adding surfactants during secondary precipitation, precipitation and spray drying. However, these methods have failed to solve the problem that the unsupported catalyst has large grains, resulting in low activity and the reactants are difficult to enter and exit the catalyst particles, resulting in more side reactions. Supported catalysts are generally prepared by deposition precipitation, impregnation and co-calcination. Common carriers include magnesium silicate, silicon dioxide and aluminum oxide. Although the supported catalyst has small grains, the introduction of a carrier also brings other problems. For example, patent CN115007163B discloses a catalyst with magnesium silicate as a carrier. The introduction of a large amount of silicon in the catalyst will cause the problem of silicon ion loss. The loss of silicon ions in the copper-bismuth catalyst will poison the subsequent 1,4-butynediol hydrogenation catalyst Raney nickel, increasing the cost of product purification. 2 O 3 The patent reports that Al 2 O 3 There will be no ion loss within the reaction pH conditions, but Al 2 O 3 A high density will increase catalyst wear. Patent CN113813973B discloses a nano-gold confined copper-based core-shell structure catalyst. 2+ and Fe 3+ The active site Cu can be stabilized by electronic effects + However, the catalyst has high raw material cost and complicated preparation process.

[0004] In summary, unsupported catalysts have the problems of low activity and high side reactions. Although the introduction of a carrier can improve the dispersion of the active components of the catalyst and thus improve the activity, it will bring other problems, such as ion loss, increased attrition and complex process. Summary of the invention

[0005] The object of the present invention is to provide a hydrophobic copper-bismuth catalyst and a preparation method for the problem that unsupported copper-bismuth catalysts have low activity and more side reactions. The catalyst strengthens the reaction mass transfer process by hydrophobically modifying the catalyst surface without introducing a carrier, thereby improving the activity and selectivity of the catalyst. According to the principle of like dissolves like, the polarity of 1,4-butynediol is greater than that of formaldehyde, so 1,4-butynediol is more soluble in water. After the catalyst is hydrophobically modified by an alkylsilane coupling agent, it is beneficial for the raw gas acetylene and formaldehyde to be enriched on the catalyst surface, thereby increasing the reaction rate. At the same time, it is beneficial for 1,4-butynediol to be more easily transferred from the catalyst surface to the water phase, which can reduce the occurrence of side reactions and thus improve the catalyst activity. The selected alkylsilane coupling agent has a small molecular weight and a small amount, and will not cause ion loss and excessive coverage of active sites. In addition, a small amount of alkylsilane coupling agent preferentially combines with high-energy active sites that are prone to side reactions, which can further improve the catalyst selectivity.

[0006] In order to achieve the purpose of the present invention, the specific technical scheme of the present invention is as follows:

[0007] A hydrophobic copper-bismuth catalyst is a carrier-free catalyst, wherein the mass fraction of copper basic carbonate is 90% to 99% (specifically 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, etc.), the mass fraction of bismuth basic carbonate is 1% to 10% (specifically 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc.), and the sum of the total mass percentages is 100%.

[0008] A method for preparing a hydrophobic copper-bismuth catalyst comprises the following steps:

[0009] (1) preparing a salt solution containing copper ions and bismuth ions, which is referred to as solution A; preparing a precipitant solution, which is referred to as solution B; preparing a solution containing a surface hydrophobic modifier, which is referred to as solution C; and preparing a hydrolysis aid, which is referred to as solution D;

[0010] As a better embodiment of the present application, the copper ion concentration of the solution 1 is 0.6-1.0 mol / L (specifically 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L, 1.0 mol / L, etc.), and the bismuth ion concentration is 0.01-0.05 mol / L (specifically 0.01 mol / L, 0.02 mol / L, 0.03 mol / L, 0.04 mol / L, 0.05 mol / L, etc.).

[0011] The step is specifically as follows: dissolving copper salt and bismuth salt in quantitative deionized water, and adding quantitative acid to prevent bismuth salt from hydrolyzing, to obtain a mixed salt solution A with a total salt ion concentration of 0.5 to 1.2 mol / L (specifically 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L, 1.0 mol / L, 1.1 mol / L, 1.2 mol / L, etc.) and a pH of 0.1 to 2 (specifically 0.1, 0.5, 1.0, 1.5, 2, etc.); preparing the same volume of alkaline solution, with a salt-alkali molar ratio of 1:1 to 1:1.3, to obtain alkaline solution B. Dissolving a hydrophobic agent in a quantitative solvent to obtain solution C; and preparing a small amount of alkaline solution as a hydrolysis aid solution D.

[0012] (2) Add deionized water into the reaction kettle 1, stir and heat to the reaction temperature;

[0013] Furthermore, the reaction temperature is 20-80°C (specifically 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, etc.).

[0014] (3) adding solution A (salt solution) and solution B (alkaline solution) to reaction kettle 1 in parallel under stirring conditions for co-precipitation, and aging the reaction solution after the addition is completed; after aging, filtering, washing, and drying to obtain a precursor;

[0015] Furthermore, during the coprecipitation reaction, the pH is controlled to be 5.0-9.0 (specifically 5, 6, 7, 8, 9, etc.), the stirring speed is 100-600 rpm, and the aging time is 0.5-4 h (specifically 0.5 h, 1 h, 1.5 h, 2 h, 2.5 h, 3 h, 3.5 h, 4 h, etc.). The mixture is washed 1-3 times (specifically 1, 2 or 3 times) with deionized water of the same temperature and volume as the aging reaction.

[0016] As a better implementation mode in the present application, the drying temperature is 80-120°C (specifically 80°C, 90°C, 100°C, 110°C, 120°C, etc.), and the drying time is 4-8h (specifically 4h, 5h, 6h, 7h, 8h, etc.).

[0017] (4) Add the precursor and solution C into reactor 2, stir and heat to the same reaction temperature as the coprecipitation, add solution D, adjust the pH, react for a period of time (preferably 1 to 4 hours, specifically 1 hour, 2 hours, 3 hours, 4 hours, etc.), filter and wash to obtain the intermediate.

[0018] (5) After adding deionized water to the intermediate, stir evenly, then add a dispersant (preferably sodium tripolyphosphate), slurry, and spray-dry after re-slurry to obtain intermediate e.

[0019] As a preferred embodiment of the present application, in step (1), the copper salt used is any one of copper nitrate, copper sulfate, copper chloride or copper acetate, or a mixture of several thereof; more preferably copper nitrate.

[0020] As a preferred embodiment of the present application, in step (1), the bismuth salt used is any one of bismuth nitrate, bismuth sulfate, bismuth chloride or bismuth acetate, or a mixture of several of them; more preferably, it is bismuth nitrate.

[0021] As a preferred embodiment of the present application, in step (1), the acid used is any one of nitric acid, sulfuric acid or hydrochloric acid or a mixture of several thereof; more preferably nitric acid.

[0022] As a preferred embodiment of the present application, in step (1), the base used is any one or a mixture of sodium hydroxide, sodium carbonate, sodium bicarbonate, ammonium carbonate or ammonium bicarbonate; more preferably, it is sodium carbonate.

[0023] As a better embodiment of the present application, in step (1), the solvent of the surface hydrophobic modifier solution is any one or two of methanol and ethanol, and a mixture of water; the surface hydrophobic modifier is any one or a mixture of several of methyltrimethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, octyltrimethoxysilane, dodecyltrimethoxysilane, hexadecyltrimethoxysilane and octadecyltrimethoxysilane.

[0024] As a better embodiment of the present application, the molar concentration of the precipitant is 0.6-2.4 mol / L (specifically 0.6 mol / L, 0.8 mol / L, 1.0 mol / L, 1.2 mol / L, 1.4 mol / L, 1.6 mol / L, 1.8 mol / L, 2.0 mol / L, 2.4 mol / L, etc.); the molar concentration of the hydrolysis aid is 0.1-0.5 mol / L (specifically 0.1 mol / L, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L, 0.5 mol / L, etc.).

[0025] Furthermore, in step (3), the coprecipitation is carried out by a dropwise addition method of parallel addition, forward addition or reverse addition, preferably parallel addition.

[0026] As a preferred embodiment of the present application, in step (4), the stirring speed is 100 to 400 rpm.

[0027] As a better implementation mode of the present application, in step (5), the solid mass fraction of the re-slurry is 20% to 50% (specifically 20%, 30%, 40%, 50%, etc.), and the spray drying temperature is 140 to 180°C (specifically 140°C, 150°C, 160°C, 170°C, 180°C, etc.).

[0028] The present invention protects a hydrophobic copper-bismuth catalyst obtained by using any one of the above methods or a reasonable combination of the methods.

[0029] The present invention also protects the use of the hydrophobic copper-bismuth catalyst described above in the synthesis of 1,4-butynediol.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) The preparation process of the hydrophobic unsupported copper-bismuth catalyst in the present invention is simple and is conducive to industrialization.

[0032] (2) After the catalyst is hydrophobically modified, it is beneficial for the reaction raw materials acetylene and formaldehyde to be enriched on the catalyst surface, thereby increasing the macroscopic reaction rate. At the same time, the hydrophilic product 1,4-butynediol is more easily desorbed from the catalyst surface to the liquid phase, thereby inhibiting the formation of the side reaction polyacetylene.

[0033] (3) The present invention uses alkyl trimethoxysilane with a relatively small molecular weight as a hydrophobic modifier. The silicon element exists in the form of a hydrophobic organic matter, which is insoluble in water and is used in a low amount, so there will be no problem of silicon ion loss. A small amount of hydrophobic modifier preferentially combines with high-energy active sites that are prone to side reactions, and will not over-cover other active sites, thereby avoiding affecting the activity of the catalyst and also improving selectivity. DETAILED DESCRIPTION

[0034] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0035] Any feature disclosed in this specification (including claims and abstract), unless otherwise stated, may be replaced by other equivalent or alternative features having similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0036] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0037] All the following raw materials are commercially available products; % not otherwise specified indicates the mass percentage, i.e. wt%.

[0038] The catalyst activity was evaluated on a slurry bed: the specific steps were as follows: 800 mL of a 37% formaldehyde aqueous solution was added to a 2 L slurry bed reactor, 50 g of the prepared copper bismuth catalyst was slurried with 100 g of water and added to the slurry bed reactor and stirring was started, an appropriate amount of sodium bicarbonate was added to adjust the solution pH to 7, acetylene and nitrogen were introduced at 80 ° C at flow rates of 14 L / h and 6 L / h, respectively, to activate the catalyst for 9 hours, and then the acetylation reaction was carried out for 7 hours, and the product composition was analyzed online using an Agilent 8890 gas chromatograph.

[0039] Embodiment 1:

[0040] A method for preparing a hydrophobic copper-bismuth catalyst comprises the following steps:

[0041] (1) Weigh 571.05 g of copper nitrate, 17.64 g of bismuth nitrate and 24.91 g of nitric acid and dissolve them in 2 L of deionized water; at the same time, weigh 297.86 g of sodium carbonate and dissolve them in 2 L of deionized water, stir to dissolve, and heat to 60°C.

[0042] (2) Add 0.3 L of deionized water to the reactor and heat to 60° C. At the same time, adjust the stirring speed of the reactor to 300 rpm / min.

[0043] (3) Add the prepared salt solution and alkali solution to the reactor 1 in parallel. After the addition is completed, reduce the speed of the stirring blade to 150 rpm / min and age for 1 hour. After aging, filter and wash the reaction slurry, and then dry it at 80° C. for 8 hours to obtain a precursor.

[0044] (4) Take 0.5 mL of methyltrimethoxysilane and dissolve it in 750 mL of ethanol, put it in reactor 2, adjust the stirring paddle of the reactor to 200 rpm, put the precursor in, then heat it to 60° C., add 10 mL of 0.1 mol / L sodium carbonate solution and react for 4 hours, then filter and wash to obtain a filter cake.

[0045] (5) 7 g of sodium tripolyphosphate was added to 340 g of deionized water, and the filter cake was added to make a slurry. The catalyst was spray-dried at 170° C. using an OMLG spray dryer to obtain a catalyst, sample number A.

[0046] Embodiment 2:

[0047] A method for preparing a hydrophobic copper-bismuth catalyst comprises the following steps:

[0048] (1) Weigh 475.28 g of copper nitrate, 15.90 g of bismuth nitrate and 22.83 g of nitric acid and dissolve them in 2 L of deionized water. At the same time, weigh 124.84 g of sodium carbonate and 94.13 g of sodium hydroxide and dissolve them in 2 L of deionized water. Stir to dissolve and heat to 70°C.

[0049] (2) Add 0.3 L of deionized water to the reactor and heat to 70° C. At the same time, adjust the stirring speed of the reactor to 400 rpm / min.

[0050] (3) Add the prepared salt solution and alkali solution to the reactor 1 in parallel. After the addition is completed, reduce the speed of the stirring blade to 200 rpm / min and age for 2 hours. After the aging is completed, filter and wash the reaction slurry, and then dry it at 100° C. for 6 hours to obtain a precursor.

[0051] (4) Take 0.4 mL of ethyltrimethoxysilane and dissolve it in 600 mL of ethanol. Place it in reactor 2. Adjust the stirring paddle of the reactor to 200 rpm and put the precursor in. Then raise the temperature to 70° C., add 4 mL of 0.2 mol / L sodium carbonate solution and react for 3 h. Filter and wash to obtain a filter cake.

[0052] (5) 7 g of sodium tripolyphosphate was added to 360 g of deionized water, and the filter cake was added to the mixture for slurrying. The mixture was spray dried at 160° C. using an OMLG spray dryer to obtain a catalyst, sample number B.

[0053] Embodiment 3:

[0054] A method for preparing a hydrophobic copper-bismuth catalyst comprises the following steps:

[0055] (1) Weigh 379.66 g of copper nitrate, 13.86 g of bismuth nitrate and 19.57 g of nitric acid and dissolve them in 2 L of deionized water. At the same time, weigh 218.97 g of sodium carbonate and dissolve them in 2 L of deionized water. Stir and dissolve them, and heat them to 80° C.

[0056] (2) Add 0.3 L of deionized water into the reactor and heat to 80°C.

[0057] (3) Adjust the stirring speed of the reactor to 500 rpm / min. Add the prepared salt solution and alkali solution to the reactor 1 in parallel. After the addition is completed, reduce the stirring speed to 200 rpm / min and age for 1.5 hours. After aging, filter and wash the reaction slurry, and then dry it at 120°C for 4 hours to obtain a precursor.

[0058] (4) Take 0.32 mL of propyltrimethoxysilane and dissolve it in 480 mL of ethanol. Place it in reactor 2. Adjust the stirring paddle of the reactor to 300 rpm and put the precursor in. Then raise the temperature to 80° C., add 8 mL of 0.2 mol / L sodium carbonate solution and react for 2 h. Filter and wash to obtain a filter cake.

[0059] (5) 7 g of sodium tripolyphosphate was added to 370 g of deionized water, and the filter cake was added to make a slurry. The catalyst was spray-dried at 150° C. using an OMLG spray dryer to obtain a catalyst, sample number C.

[0060] Embodiment 4:

[0061] A method for preparing a hydrophobic copper-bismuth catalyst comprises the following steps:

[0062] (1) Weigh 522.81 g of copper nitrate, 17.49 g of bismuth nitrate and 24.70 g of nitric acid and dissolve them in 2 L of deionized water. At the same time, weigh 149.67 g of sodium carbonate and 112.96 g of sodium hydroxide and dissolve them in 2 L of deionized water. Stir to dissolve and heat to 60°C.

[0063] (2) Add 0.3 L of deionized water into the reactor and heat to 60° C. while adjusting the stirring speed of the reactor to 300 rpm / min.

[0064] (3) Add the prepared salt solution and alkali solution to the reactor 1 in parallel. After the addition is completed, reduce the speed of the stirring blade to 150 rpm / min and age for 1 hour. After the aging is completed, filter and wash the reaction slurry, and then dry it at 105° C. for 5 hours to obtain a precursor.

[0065] (4) Take 0.5 mL of octyltrimethoxysilane and dissolve it in 750 mL of ethanol. Place it in reactor 2. Adjust the stirring paddle of the reactor to 200 rpm and put the precursor in. Then raise the temperature to 60° C., add 3 mL of 0.3 mol / L sodium carbonate solution and react for 4 h. Filter and wash to obtain a filter cake.

[0066] (5) 8 g of sodium tripolyphosphate was added to 400 g of deionized water, and the filter cake was added to make a slurry. The catalyst was spray-dried at 160° C. using an OMLG spray dryer to obtain a catalyst, sample number D.

[0067] Embodiment 5:

[0068] A method for preparing a hydrophobic copper-bismuth catalyst comprises the following steps:

[0069] (1) Weigh 428.29 g of copper nitrate, 13.23 g of bismuth nitrate and 18.68 g of nitric acid and dissolve them in 2 L of deionized water. At the same time, weigh 253.86 g of sodium carbonate and dissolve them in 2 L of deionized water. Stir to dissolve and heat to 70°C.

[0070] (2) Add 0.3 L of deionized water into the reactor and heat to 70° C. while adjusting the stirring speed of the reactor to 300 rpm / min.

[0071] (3) Add the prepared salt solution and alkali solution to the reactor 1 in parallel. After the addition is completed, reduce the speed of the stirring blade to 150 rpm / min and age for 2 hours. After the aging is completed, filter and wash the reaction slurry, and then dry it at 110° C. for 4 hours to obtain a precursor.

[0072] (4) Take 0.4 mL of hexadecyltrimethoxysilane and dissolve it in 600 mL of ethanol. Place it in reactor 2. Adjust the stirring paddle of the reactor to 200 rpm and put the precursor in. Then raise the temperature to 70° C., add 8 mL of 0.1 mol / L sodium carbonate solution and react for 4 h. Filter and wash to obtain a filter cake.

[0073] (5) 8 g of sodium tripolyphosphate was added to 420 g of deionized water, and the filter cake was added to make a slurry. The catalyst was spray-dried at 150° C. using an OMLG spray dryer to obtain a catalyst, sample number E.

[0074] Comparative Example 1:

[0075] The preparation of the catalyst was the same as in Example 2, except that sodium tripolyphosphate was not added in step (5). That is, the filter cake was directly added to 420 g of deionized water for slurrying, and spray-dried at 150° C. using an OMLG spray dryer to obtain a catalyst, sample number F.

[0076] Comparative Example 2:

[0077] The preparation of the catalyst is the same as in Example 5, except that step 4 is omitted, and the remaining steps are the same. The catalyst sample obtained is numbered G.

[0078] The samples obtained in Examples 1-5 and Comparative Examples 1-2 were subjected to catalyst activity evaluation, and the specific results are shown in Table 1.

[0079] Table 1: Catalyst activity evaluation results

[0080] Sample No. Formaldehyde conversion rate (%) 1,4-Butynediol selectivity (%) A 93.0％ 96％ B 95.2％ 98.2％ C 97.4％ 98.3％ D 93.0％ 98.2％ E 89.3％ 98.0％ F 94.5％ 96.2％ G 92.8％ 94.5％

[0081] The above-mentioned embodiments only express the specific implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the protection scope of the present application. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the technical solution concept of the present application, and these all belong to the protection scope of the present application.

[0082] This background section is provided to generally present the context of the invention, and the work of the presently named inventors, the work to the extent described in this background section, and aspects of this section that did not constitute prior art at the time of application are neither explicitly nor implicitly admitted to be prior art to the present invention.

Claims

1. A method for preparing a hydrophobic copper-bismuth catalyst, characterized in that: The synthesis steps include: (1) preparing a salt solution containing copper ions and bismuth ions, denoted as solution A; A precipitant solution is prepared, which is referred to as solution B; a solution containing a surface hydrophobic modifier is prepared, which is referred to as solution C; Prepare a hydrolysis aid, which is called solution D; (2) adding ionized water into the reaction kettle 1, stirring and heating to the reaction temperature; (3) adding solution A and solution B to the reactor 1 in parallel for reaction; after the addition is completed, the reaction solution is aged; After aging, filtering, washing and drying are performed to obtain a precursor; (4) Add the precursor and solution C to reactor 2, stir and heat to the reaction temperature, then add solution D, adjust the pH, and after reacting for a period of time, filter and wash to obtain an intermediate; (5) The intermediate is placed in deionized water, stirred evenly, and deionized water containing a dispersant is added to re-slurry, and the catalyst is obtained after spray drying.

2. The preparation method according to claim 1, characterized in that: In the solution A described in step (1), the copper source containing copper ions is at least one of copper nitrate, copper sulfate, copper chloride and copper acetate; the bismuth source containing bismuth ions is at least one of bismuth nitrate, bismuth sulfate, bismuth chloride and bismuth acetate; the copper ion concentration is 0.6-1.0 mol / L, and the bismuth ion concentration is 0.01-0.05 mol / L.

3. The preparation method according to claim 1, characterized in that: In step (1), the precipitant and the hydrolysis aid are at least one of sodium bicarbonate, sodium carbonate, ammonium carbonate and potassium carbonate; in the precipitant solution, the concentration of the precipitant is 0.6-2.4 mol / L; the concentration of the hydrolysis aid is 0.1-0.5 mol / L.

4. The preparation method according to claim 1, characterized in that: In step (1), in the solution containing the surface hydrophobic modifier, the surface hydrophobic modifier is any one of methyltrimethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, octyltrimethoxysilane, dodecyltrimethoxysilane, hexadecyltrimethoxysilane and octadecyltrimethoxysilane, or a mixture of several thereof; the volume concentration of the surface hydrophobic modifier is 0.01% to 0.1%, and the solvent used is methanol, ethanol or a mixture of one of them and water.

5. The preparation method according to claim 1, characterized in that: In step (2), the reaction temperature is 20-80°C.

6. The preparation method according to claim 1, characterized in that: In step (3), the pH value of the reaction in the reactor 1 is 5.0-9.0, the stirring speed is 100-600 rpm, the aging time is 0.5-4h, the aging temperature is 20-80°C, and the aging reaction is washed 1-3 times with deionized water of the same temperature and volume.

7. The preparation method according to claim 1, characterized in that: In step (4), the reaction pH is controlled to be 7.0-10.0, the reaction temperature is 20-80° C., the stirring speed is 100-400 rpm, and the reaction time is 1-4 h; and deionized water of the same temperature and volume is used for washing 1-3 times in sequence.

8. The preparation method according to claim 1, characterized in that: The dispersant added in step (5) is sodium tripolyphosphate; the solid content of the re-slurry is 20wt% to 50wt%.

9. A hydrophobic copper-bismuth catalyst prepared by any one of the methods of claims 1 to 8, characterized in that: In the catalyst, the mass fraction of copper basic carbonate is 90% to 99%, the mass fraction of bismuth basic carbonate is 1% to 10%, and the total mass percentage is 100%.

10. Use of the hydrophobic copper-bismuth catalyst according to claim 9 in the synthesis of 1,4-butynediol.