Monatomic alloy catalyst as well as preparation method and application thereof

Abstract

The invention relates to the technical field of catalysts, in particular to a monatomic alloy catalyst and a preparation method and application thereof. A carrier of the monatomic alloy catalyst comprises a porous carbon material, active components of the monatomic alloy catalyst comprise precious metal M and heavy metal N, the precious metal M comprises at least one of Ru, Pt or Pd, and the heavy metal N comprises at least one of Bi or Sb. The monatomic alloy catalyst has higher effective hydrogenation kinetics, improves the adaptability of active sites and reactant adsorption and product desorption behaviors, and has higher activity, selectivity and stability when being used in a reaction for generating BDO through BYD hydrogenation.

Description

Technical Field

[0001] The present invention relates to the field of catalyst technology, and in particular to a single-atom alloy catalyst and a preparation method and application thereof. Background Art

[0002] The downstream products of 1,4-butanediol (BDO), polybutylene succinate and polybutylene adipate terephthalate copolyesters, can be used to produce biodegradable plastics. This aligns with my country's commitment to sustainable development, making the vigorous development of the 1,4-butanediol industry a major trend. Consequently, the production process of 1,4-butanediol has become a research hotspot in recent years. The current mainstream 1,4-butanediol synthesis route involves the catalytic formaldehydeation of acetylene to 1,4-butynediol (BYD), followed by direct hydrogenation of BYD to produce BDO. BYD hydrogenation is a complex process, and currently, industrial BYD hydrogenation is hampered by factors such as H2 diffusion and low catalyst activity. Consequently, the reaction often initially produces 1,4-butenediol (BED), which is then further hydrogenated to produce BDO. The formation of BED, in turn, leads to the production of a wide range of byproducts. For example, BED undergoes double bond isomerization upon hydrogenation to produce γ-hydroxybutyraldehyde, which rapidly converts to the stable hemiacetal 2-hydroxytetrahydrofuran (2-OH-THF), or further reacts with alcohols to produce acetals. Double bond isomerization, accompanied by hydrogenolysis, produces crotonaldehyde and butanol. Among these byproducts, 2-hydroxytetrahydrofuran is difficult to remove from the final product by distillation, severely impacting BDO product quality and yield. Therefore, a crucial factor in determining BDO product selectivity is the ability to promptly hydrogenate the BED produced during the reaction to produce the final BDO product.

[0003] Currently, most research and production of BDO by hydrogenation from BYD utilizes high-temperature and high-pressure reaction conditions. These conditions can easily lead to an increase in byproducts, reducing the selectivity of the target product and increasing the cost of subsequent purification. For example, nickel-based catalysts require high temperatures (greater than 140°C) and high pressures (greater than 10 MPa) to achieve high BDO selectivity. In industrial applications, high-temperature and high-pressure reaction conditions inevitably increase production costs and reduce safety, so reducing reaction temperature and pressure is also a significant concern. Furthermore, excessively high reaction temperatures can lead to catalyst deactivation due to carbon deposition, and the handling and storage of spent catalysts can cause significant environmental pollution. Therefore, achieving BDO production under mild conditions has become an urgent challenge in the industrialization of BDO by hydrogenation from BYD.

[0004] In summary, both the purity of the BDO product and the production conditions significantly impact the industry's production costs in the industrialization of BYD hydrogenation to BDO. Therefore, striving for milder reaction conditions and higher product selectivity has become a development goal for the industry.

[0005] To achieve this goal, it is necessary to develop high-performance catalysts suitable for the industrialization of BYD hydrogenation to BDO. The selection of high-performance catalysts generally follows the following principles: (1) high activity; (2) high catalytic selectivity; (3) long catalytic life; (4) environmental friendliness, green production process, and simple preparation. Currently, transition metal catalysts such as Cu and Ni and precious metal catalysts such as Ru, Pt, and Pd are commonly used as hydrogenation catalysts in industry. Among them, transition metal catalysts are relatively low in cost, but the high temperature and high pressure reaction conditions required and the environmental pollution caused by the short catalyst life have hindered the development of the industrialization of BYD hydrogenation to BDO. Precious metal catalysts have higher activity than transition metal catalysts, but the cost of precious metal catalysts is also relatively high, and high-activity precious metal catalysts are more likely to cause a decrease in product selectivity in the BYD hydrogenation to BDO reaction. For example, in a fixed-bed reactor, BYD was hydrogenated using a 1% Ru / CaCO3 catalyst at a reaction temperature of 100°C and a hydrogen pressure of 2 MPa, achieving a 66% selectivity for the byproduct BED. Furthermore, a Ru / ZIF-8 catalyst, obtained by loading a nanostructured ruthenium sol onto ZIF-8, exhibited high activity in the BYD hydrogenation reaction, but exhibited poor selectivity for the target product, BDO (<6%). Therefore, reducing the amount of precious metal in the catalyst while simultaneously improving BDO selectivity without compromising catalytic activity has become a major challenge in the industrial application of BYD hydrogenation to BDO.

[0006] Single-atom catalysts have been extensively explored and studied in the past few years due to their ultra-high atomic utilization and high activity. For noble metal catalysts, higher noble metal atom utilization means lower noble metal loading, so noble metal single-atom catalysts hold great promise for the industrial application of BYD hydrogenation to BDO. However, to date, no noble metal catalyst has been developed that can simultaneously achieve mild reaction conditions and high product selectivity in the BYD hydrogenation to BDO reaction. Therefore, developing a catalyst with high catalytic activity, long service life, and high product selectivity in the BYD hydrogenation to BDO reaction is essential for the development of this industry to reduce the cost of BOD production, simplify reaction conditions, and minimize environmental pollution. Summary of the Invention

[0007] The present invention aims to at least partially address one of the technical problems in the related art. To this end, the present invention provides a single-atom alloy catalyst, its preparation method, and its application. This single-atom alloy catalyst exhibits enhanced effective hydrogenation kinetics, improved compatibility of active sites with reactant adsorption and product desorption behaviors, and exhibits enhanced activity, selectivity, and stability in the hydrogenation of BYD to BDO.

[0008] To this end, the first aspect of the present invention provides a single-atom alloy catalyst, the carrier of the single-atom alloy catalyst includes a porous carbon material, the active components include a precious metal M and a heavy metal N, the precious metal M includes at least one of Ru, Pt or Pd, and the heavy metal N includes at least one of Bi or Sb.

[0009] The active component of the single-atom alloy catalyst, the noble metal M, is loaded on the support surface in the form of a single atom, and the heavy metal N is coupled to the M single-atom active site. The resulting catalyst exhibits higher activity, selectivity, and longer life in the hydrogenation of 1,4-butynediol to produce 1,4-butanediol. Specifically, the heavy metal N is anchored around the noble metal M. On the one hand, a spatial constraint is formed between the M atoms and the N atoms. This spatial constraint inhibits the migration of the M atoms during the reaction caused by the sharp increase in surface free energy after the noble metal M is loaded on the support surface in the form of a single atom. After the surface free energy of the noble metal M atoms is suppressed by the heavy metal N, the anti-sintering and anti-coking capabilities of the M active sites are improved, thereby inhibiting the catalyst deactivation problem caused by the agglomeration of metal atoms during the BYD hydrogenation to BDO reaction; on the other hand, the synergistic effect between the M atoms and the N atoms can improve the effective hydrogenation kinetics of the noble metal M atoms. Higher effective hydrogenation kinetics improve the interaction between the active sites and the adsorption of reactants and the desorption of products. Due to the adaptability of the BYD hydrogenation reaction, the intermediate product BED is often formed first in the BYD hydrogenation reaction process, and then further hydrogenated to produce BDO. The higher effective hydrogenation kinetics reduces the existence time of the intermediate product BED produced in the BYD hydrogenation process to produce BDO, so that the BED produced in the reaction process can be further hydrogenated and converted into the final product BDO in a timely manner. The reduction of by-product BED in the reaction process significantly reduces by-products such as γ-hydroxybutyraldehyde, hemiacetal 2-hydroxytetrahydrofuran (2-OH-THF), acetal, crotonaldehyde, and butanol produced due to excessive BED, thereby further significantly increasing the selectivity of the BYD hydrogenation process to produce BDO and the intermediate product BDO. The higher BDO selectivity reduces the cost of product purification and separation.

[0010] This single-atom alloy catalyst not only improves the utilization rate of precious metal M atoms and reduces the cost of the catalyst, but also has higher activity and stability. The synergistic effect of precious metal M atoms and heavy metal N atoms greatly reduces the content of by-products in the reaction, indicating that the single-atom alloy catalyst provided by the present invention is a highly potential catalyst alternative for the hydrogenation of 1,4-butynediol to prepare 1,4-butanediol.

[0011] According to an embodiment of the present invention, the mass proportion of the noble metal M in the single-atom alloy catalyst is 0.2%-1.5%, and the mass proportion of the heavy metal N is 0.1%-1%.

[0012] According to an embodiment of the present invention, the carrier is a carrier activated by an alkaline substance, and the mass proportion of the alkaline substance in the carrier is 0.05%-1%.

[0013] A second aspect of the present invention provides a method for preparing the single-atom alloy catalyst described in the first aspect, comprising:

[0014] preparing a solution comprising a first complexing agent and an alcohol compound, and adding a noble metal M precursor to obtain an M precursor complex solution;

[0015] preparing a solution comprising a first complexing agent and an alcohol compound, and adding a noble metal M precursor to obtain an M precursor complex solution;

[0016] Adding the M precursor complex solution to the support, and performing freeze-drying treatment to obtain a first intermediate of the single-atom alloy catalyst;

[0017] The first intermediate of the single-atom alloy catalyst is immersed in a metal salt solution, and a second intermediate of the single-atom alloy catalyst is obtained by drying and calcining.

[0018] dissolving the single-atom alloy catalyst second intermediate in an acidic solution to obtain a single-atom alloy catalyst third intermediate;

[0019] A solution containing a heavy metal N precursor is prepared, the solution is mixed with a second complexing agent to obtain a N precursor complex solution, the N precursor complex solution is added to the single atom alloy catalyst third intermediate, and the single atom alloy catalyst is obtained by freeze-drying.

[0020] This preparation method uses a complexing agent to modify the noble metal M and heavy metal N to construct a MOF structure, and uses two-step coordination adsorption to load them on the surface of a carbon material carrier, respectively, to obtain a high-performance hydrogenation catalyst with a uniform distribution of bimetallic single atoms. Compared with traditional catalyst preparation methods, the preparation method provided by the present invention allows the noble metal component to be highly dispersed in the catalyst in a single atom, and the heavy metal N is distributed around the noble metal. The spatial constraint formed between the single-atom noble metal M and the heavy metal N inhibits the migration and agglomeration of atoms caused by the sharp increase in the surface free energy of the single-atom noble metal after being loaded on the carrier surface. This inhibitory effect can improve the anti-sintering and anti-coking effects of the noble metal active sites in the reaction of hydrogenating 1,4-butynediol to prepare 1,4-butanediol. The synergistic effect between M and N atoms can improve the effective hydrogenation kinetics of the noble metal M atoms. Higher effective hydrogenation kinetics improve the adaptability of the active sites to reactant adsorption and product desorption behaviors, thereby reducing the lifetime of the intermediate product BED produced during the hydrogenation of BYD to BDO. This allows the BED intermediate produced during the reaction to be further hydrogenated and converted into the final product BDO in a timely manner. The addition of heavy metal N as a co-catalyst improves the activity, selectivity, and stability of the catalyst in the hydrogenation of 1,4-butynediol to 1,4-butanediol.

[0021] According to an embodiment of the present invention, the first complexing agent includes diethyldithiocarbamate.

[0022] According to an embodiment of the present invention, the alcohol compound includes at least one of inositol, tryptophan, mannitol or furfuryl alcohol.

[0023] According to an embodiment of the present invention, the noble metal M precursor includes at least one of a Ru precursor, a Pt precursor, and a Pd precursor;

[0024] The Ru precursor includes at least one of ruthenium trichloride, ruthenium nitrate, ruthenium ammonium chloride or ruthenium acetate;

[0025] The Pt precursor includes at least one of chloroplatinic acid, tetraammineplatinum dichloride, diethanolamine hexahydroxyplatinate or platinum nitrate;

[0026] The Pd precursor includes at least one of palladium dichloride, palladium nitrate, palladium hydroxide or palladium sulfate.

[0027] According to an embodiment of the present invention, the carrier is an activated carrier, and the activation treatment includes impregnating the carrier with an alkaline solution.

[0028] According to an embodiment of the present invention, the M precursor complex solution is added to the carrier at 0-5°C.

[0029] According to an embodiment of the present invention, the metal salt in the metal salt solution includes sodium chloride and potassium chloride, and the mass ratio of sodium chloride to potassium chloride in the metal salt solution is (1-5):1.

[0030] According to an embodiment of the present invention, the calcination treatment is carried out at a temperature of 600-800° C. and for a time of 1-4 hours.

[0031] According to an embodiment of the present invention, the heavy metal N precursor includes at least one of a Bi precursor or a Sb precursor; the Bi precursor includes at least one of bismuth chloride, bismuth vanadate, bismuth nitrate, bismuth bromide or bismuth iodate; the Sb precursor includes at least one of antimony nitrate, antimony sulfate, antimony trichloride, antimony nitride, antimony carbonate, antimony bromide or antimony sulfide.

[0032] According to an embodiment of the present invention, the second complexing agent includes C 24 H 34 N8O4S2.

[0033] The third aspect of the present invention provides a use of the single-atom alloy catalyst described in the first aspect or the single-atom alloy catalyst obtained according to the method described in the second aspect in the hydrogenation of 1,4-butynediol to prepare 1,4-butanediol.

[0034] The active components of the single-atom alloy catalyst include precious metal M and heavy metal N, wherein the precious metal M is loaded on the support surface in the form of a single atom, and the heavy metal N is anchored around the precious metal M. On the one hand, a spatial constraint is formed between the M atoms and the N atoms. This spatial constraint inhibits the migration of the M atoms during the reaction caused by the sharp increase in surface free energy after the precious metal M is loaded on the support surface in the form of a single atom. After the surface free energy of the precious metal M atoms is suppressed by the heavy metal N, the anti-sintering and anti-coking capabilities of the M active sites are improved, thereby inhibiting the catalyst deactivation problem caused by the agglomeration of metal atoms during the BYD hydrogenation to BDO reaction; on the other hand, the synergistic effect between the M atoms and the N atoms can improve the effective hydrogenation kinetics of the precious metal M atoms, and higher effective hydrogenation kinetics. The adaptability of active sites to reactant adsorption and product desorption behavior is improved. The BYD hydrogenation reaction often first forms the intermediate product BED, which is then further hydrogenated to BDO. The higher effective hydrogenation kinetics reduce the lifetime of the intermediate BED produced during the BYD hydrogenation to BDO process, allowing the BED produced during the reaction to be promptly hydrogenated and converted to the final product BDO. The reduction in byproduct BED during the reaction significantly reduces byproducts such as γ-hydroxybutyraldehyde, hemiacetal 2-hydroxytetrahydrofuran (2-OH-THF), acetal, crotonaldehyde, and butanol produced due to excessive BED, thereby significantly increasing the selectivity of the BYD hydrogenation to BDO production process and the intermediate product BDO. The higher BDO selectivity reduces product purification and separation costs.

[0035] A fourth aspect of the present invention provides a method for preparing 1,4-butanediol by hydrogenating 1,4-butynediol, the method comprising: using a single-atom alloy catalyst to catalyze the hydrogenation of 1,4-butynediol to prepare 1,4-butanediol;

[0036] The single-atom alloy catalyst is the single-atom alloy catalyst described in the first aspect or the single-atom alloy catalyst obtained according to the method described in the second aspect.

[0037] This method has low cost, simple reaction conditions, high selectivity for 1,4-butanediol, and reduces pollution to the environment.

[0038] According to an embodiment of the present invention, the temperature for preparing 1,4-butanediol by hydrogenation of 1,4-butynediol is 20-200° C. and the pressure is 0.1-15 MPa.

[0039] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0041] Figure 1 shows a transmission electron micrograph of the 1%Ru-1%Bi / AC catalyst prepared in Example 1 of the present invention;

[0042] Figure 2 Shows a high-angle annular dark-field scanning transmission electron microscopy image of the Ru element in the 1%Ru-1%Bi / AC catalyst prepared in Example 1 of the present invention;

[0043] Figure 3 A high-angle annular dark-field scanning transmission electron microscopy image of the Bi element in the 1%Ru-1%Bi / AC catalyst prepared in Example 1 of the present invention is shown;

[0044] Figure 4 The figure shows a transmission electron microscope image of the 1% Pt-1% Sb / AC catalyst prepared in Example 3 of the present invention. DETAILED DESCRIPTION

[0045] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be understood as limiting the present invention.

[0046] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, features defined as "first" or "second" may explicitly or implicitly include one or more of such features. Furthermore, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0047] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0048] In order to make the present invention more easily understood, certain technical and scientific terms are specifically defined below. Unless otherwise clearly defined elsewhere in this document, all other technical and scientific terms used herein have the meaning commonly understood by those skilled in the art to which the present invention belongs.

[0049] In this document, the terms “include” or “comprising” are open expressions, that is, including the contents specified in the present invention, but not excluding other contents.

[0050] As used herein, the terms "optionally," "optional," or "optionally" generally mean that the subsequently described event or circumstance may but need not occur, and that the description includes instances where the event or circumstance occurs and instances where it does not.

[0051] According to an embodiment of the present invention, a first aspect of the present invention provides a single-atom alloy catalyst, wherein the carrier of the single-atom alloy catalyst includes a porous carbon material, the active components include a precious metal M and a heavy metal N, the precious metal M includes at least one of Ru, Pt or Pd, and the heavy metal N includes at least one of Bi or Sb.

[0052] The single-atom alloy catalyst provided by the present invention has a uniform distribution of bimetallic single atoms, with the noble metal M being highly monoatomically dispersed within the catalyst, and the heavy metal N being distributed around the noble metal. The spatial confinement formed between the single-atom noble metal M and heavy metal N particles inhibits atomic migration and aggregation, which is caused by the sharp increase in surface free energy after the noble metal is loaded as a single atom on the support surface. This inhibitory effect improves the sintering and coking resistance of the noble metal active sites in the hydrogenation of 1,4-butynediol to 1,4-butanediol. The synergistic effect between the M and N atoms improves the effective hydrogenation kinetics of the noble metal M atoms. Higher effective hydrogenation kinetics improve the adaptability of the active sites to reactant adsorption and product desorption, thereby reducing the lifetime of the intermediate BED produced during the hydrogenation of BYD to BDO. This allows the BED intermediate produced during the reaction to be further hydrogenated and converted into the final product, BDO. The addition of the noble metal N as a co-catalyst improves the catalyst's activity, selectivity, and stability in the hydrogenation of 1,4-butynediol to 1,4-butanediol.

[0053] According to a specific embodiment of the present invention, the mass proportion of the precious metal M in the single-atom alloy catalyst is 0.2%-1.5%. As some specific examples, the mass proportion of the precious metal M in the single-atom alloy catalyst can be 0.2%, 0.3%, 0.4%, 0.5%, 1%, 1.5%, etc.

[0054] According to a specific embodiment of the present invention, the mass proportion of heavy metal N in the single-atom alloy catalyst is 0.1%-1%. As some specific examples, the mass proportion of heavy metal N in the single-atom alloy catalyst can be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 1%, etc.

[0055] According to a specific embodiment of the present invention, the carrier includes a porous carbon material, wherein the type of the porous carbon material is not particularly limited, and includes but is not limited to activated carbon. Specifically, the carrier may be a carrier that has been activated, so that the surface of the carrier after the activation treatment can obtain more surface functional groups required for adsorbing metals. The activation treatment can be specifically performed by an alkaline substance, and the type of the alkaline substance is not particularly limited, and includes but is not limited to hydroxide. The mass proportion of the alkaline substance in the carrier may be 0.05%-1%. As some specific examples, the mass proportion of the alkaline substance in the carrier may be 0.05%, 0.1%, 0.5%, 1%, etc.

[0056] According to an embodiment of the present invention, a second aspect of the present invention provides a method for preparing the single-atom alloy catalyst according to the first aspect, the method comprising:

[0057] (1) A solution containing a first complexing agent and an alcohol compound is prepared, and a noble metal M precursor is added to obtain an M precursor complex solution.

[0058] In this step, a complexing agent can be used to modify the noble metal M to construct a MOF structure.

[0059] According to a specific embodiment of the present invention, the type of the complexing agent is not particularly limited, and includes but is not limited to diethyldithiocarbamate, such as sodium diethyldithiocarbamate [(CH2)5NCS2Na].

[0060] According to a specific embodiment of the present invention, the type of the alcohol compound is not particularly limited, and includes but is not limited to inositol, tryptophan, mannitol, furfuryl alcohol, etc.

[0061] According to a specific embodiment of the present invention, the solution can be prepared by dissolving the first complexing agent and the alcohol compound in an acidic solution. The acidic solution can be a commonly used acidic solution such as hydrochloric acid, and its concentration can be 0.02-0.1 mol / L, for example, 0.02 mol / L, 0.04 mol / L, 0.06 mol / L, 0.08 mol / L, 0.1 mol / L, etc.

[0062] According to a specific embodiment of the present invention, the noble metal M precursor includes at least one of a Ru precursor, a Pt precursor, and a Pd precursor. The Ru precursor may be selected from corresponding chloride salts, nitrates, acetates, etc., including but not limited to ruthenium trichloride, ruthenium nitrate, ruthenium chloride ammonia, and ruthenium acetate. The Pt precursor may be selected from corresponding chloride salts, nitrates, amine salts, etc., including but not limited to chloroplatinic acid, dichlorotetraammineplatinum, hexahydroxyplatinic acid diethanolamine, and platinum nitrate. The Pd precursor may be selected from corresponding chloride salts, nitrates, sulfates, hydroxides, etc., including but not limited to palladium dichloride, palladium nitrate, palladium hydroxide, and palladium sulfate.

[0063] (2) Adding the M precursor complex solution to the carrier, and performing freeze-drying treatment to obtain the first intermediate of the single-atom alloy catalyst.

[0064] In this step, the M precursor complex solution is loaded on the carrier in a coordinated adsorption manner to form a first intermediate of the single-atom alloy catalyst.

[0065] According to a specific embodiment of the present invention, the support may be an activated support, wherein the activation treatment comprises impregnating the support with an alkaline solution. The alkaline substance in the alkaline solution includes, but is not limited to, a hydroxide, such as sodium hydroxide. Specifically, after the impregnation treatment, the support may be dried before being used in subsequent preparation steps.

[0066] According to a specific embodiment of the present invention, the M precursor complex solution is added to the carrier at 0-5°C. Specifically, the method of adding is not particularly limited. The carrier can be placed in an environment of 0-5°C and the M precursor complex solution can be added to the carrier in a dropwise manner; or the carrier can be placed in an environment of 0-5°C and the M precursor complex solution can be added to the carrier all at once. The above methods do not affect the adsorption effect. At the same time, the speed of the dropwise addition can be selected according to the dropwise addition situation, for example, 0.2-0.5 mL / min.

[0067] According to a specific embodiment of the present invention, the amount of liquid nitrogen added per gram of carrier in the freeze-drying process may be 0.05-0.2 mL, the specific drying temperature may be -5-5° C., and the vacuum degree may be -0.09-0.1 MPa.

[0068] According to a specific embodiment of the present invention, the intermediate may be dried after freeze-drying. The drying process may be carried out by using equipment such as an oven. As some specific examples, the drying temperature may be 100° C. and the drying time may be 2 hours.

[0069] (3) The first intermediate of the single-atom alloy catalyst is immersed in a metal salt solution, and a second intermediate of the single-atom alloy catalyst is obtained by drying and calcining.

[0070] According to a specific embodiment of the present invention, the metal salt solution can be used as a reaction medium for forming a metal alloy during the calcination process. The type of the metal salt solution is not particularly limited, and is preferably a metal chloride salt, more preferably comprising sodium chloride and potassium chloride. The mass ratio of sodium chloride to potassium chloride in the metal salt solution is (1-5):1, for example, 1:1, 2:1, 3:1, 4:1, 5:1, etc.

[0071] According to a specific embodiment of the present invention, the temperature and time of the drying process are not particularly limited, and those skilled in the art can adjust them according to the drying conditions.

[0072] According to specific embodiments of the present invention, the temperature and time of the calcination treatment are not particularly limited. As some specific examples, the temperature of the calcination treatment may be 600-800°C, and the time may be 1-4 hours. Preferably, the calcination treatment is performed in an inert atmosphere, wherein the inert atmosphere includes at least one of N2, Ar, and He.

[0073] (4) Dissolving the second intermediate of the single-atom alloy catalyst in an acidic solution to obtain a third intermediate of the single-atom alloy catalyst.

[0074] In this step, the metal elements introduced into the second intermediate of the single-atom alloy catalyst by the metal salt solution are removed by an acidic solution.

[0075] According to a specific embodiment of the present invention, the type of the acidic solution is not particularly limited, and includes but is not limited to a hydrochloric acid solution.

[0076] According to a specific embodiment of the present invention, this step may further include a subsequent washing treatment, that is, dissolving the single-atom alloy catalyst second intermediate in a second acidic solution, and then washing with deionized water to further remove the metal elements introduced by the metal salt solution.

[0077] (5) preparing a solution containing a heavy metal N precursor, mixing the solution with a second complexing agent to obtain a N precursor complex solution, adding the N precursor complex solution to the third intermediate of the single-atom alloy catalyst, and obtaining the single-atom alloy catalyst by freeze-drying.

[0078] In this step, the heavy metal N precursor reacts with the complexing agent to form an organic ligand, which is loaded on the carrier in a coordinated adsorption manner to form a single-atom alloy catalyst.

[0079] According to a specific embodiment of the present invention, the type of the heavy metal N precursor is not particularly limited, and includes but is not limited to a Bi precursor and a Sb precursor. The Bi precursor includes but is not limited to bismuth chloride, bismuth vanadate, bismuth nitrate, bismuth bromide, and bismuth iodate; the Sb precursor includes but is not limited to antimony nitrate, antimony sulfate, antimony trichloride, antimony nitride, antimony carbonate, antimony bromide, and antimony sulfide.

[0080] According to a specific embodiment of the present invention, the solution containing the heavy metal N precursor can be obtained by dissolving the heavy metal N precursor in an acidic solution, and the acidic solution includes but is not limited to hydrochloric acid.

[0081] According to a specific embodiment of the present invention, the type of the second complexing agent is not particularly limited, including but not limited to thiamine disulfide compounds (C 24 H 34 Specifically, in order to further improve the dispersibility of the second complexing agent in the solution, the solution can be mixed with the second complexing agent and a dispersant, wherein the dispersant includes but is not limited to toluene.

[0082] According to a specific embodiment of the present invention, the method of adding the N precursor complex solution into the single atom alloy catalyst third intermediate is not particularly limited, and the solution can be added by titration or the like.

[0083] According to an embodiment of the present invention, the third aspect of the present invention provides the use of the single-atom alloy catalyst described in the first aspect or the single-atom alloy catalyst obtained according to the method described in the second aspect in the hydrogenation of 1,4-butynediol to prepare 1,4-butanediol.

[0084] According to an embodiment of the present invention, a fourth aspect of the present invention provides a method for preparing 1,4-butanediol by hydrogenating 1,4-butynediol, the method comprising: catalyzing the hydrogenation of 1,4-butynediol to prepare 1,4-butanediol using a single-atom alloy catalyst;

[0085] The single-atom alloy catalyst is the single-atom alloy catalyst described in the first aspect or the single-atom alloy catalyst obtained according to the method described in the second aspect.

[0086] According to a specific embodiment of the present invention, in the method, 1,4-butynediol can be reacted in a solution, and the solvent can be water or the like. The mass proportion of 1,4-butynediol in the solution can be 5%-30%.

[0087] According to a specific embodiment of the present invention, the reactor used in the method includes but is not limited to a micro-packed bed reactor.

[0088] According to a specific embodiment of the present invention, the temperature for hydrogenating 1,4-butynediol to prepare 1,4-butanediol can be 20-200° C., the reaction pressure is 0.1-15 MPa, and the time can be adjusted according to the preparation conditions, for example, 1-2000 h.

[0089] Below, the scheme of the present invention will be explained in conjunction with embodiment.It will be understood by those skilled in the art that the following examples are only used to illustrate the present invention and should not be regarded as limiting the scope of the present invention.In the embodiment, if specific technology or conditions are not indicated, the technology or conditions described in the literature in this area or the product instructions are used.The reagents or instruments used are not indicated by the manufacturer, and are all conventional products that can be obtained by commercial purchase.

[0090] Example 1

[0091] Weigh 0.25 g of sodium diethyldithiocarbamate and 0.5 g of furfuryl alcohol and dissolve them in 20 g of dilute hydrochloric acid solution (0.05 mol / L). Add 4.945 mL of RuCl3 solution (0.2 mol / L) dropwise while stirring, and stir at room temperature for 3 h. After stirring, store at room temperature for use.

[0092] Weigh 0.2 g of NaOH and dissolve it in 20 g of water. Use the initial impregnation method to impregnate 10 g of dried activated carbon support (AC). After completion, place the activated carbon in a vacuum drying oven at 50 ° C for 12 h to obtain AC-NaOH.

[0093] The Ru precursor solution was loaded onto the AC-NaOH support by coordination adsorption to form Ru-MOF / AC. Liquid nitrogen was then immediately injected to freeze the catalyst, which was then vacuum dried at 0°C. After vacuum drying, the catalyst was placed in an oven at 100°C for 2 hours to obtain the Ru-MOF / AC catalyst.

[0094] 0.07 g NaCl and 0.02 g KCl were weighed and dissolved in 15 g water, and then impregnated into the dried catalyst using the initial impregnation method, and then placed in a 50 ° C oven for 12 h;

[0095] The dried catalyst was placed in a tube furnace and heated to 700°C at a rate of 2°C / min under a nitrogen atmosphere. The temperature was maintained at 700°C for 2 hours before being cooled to room temperature. The catalyst was then immersed in 100 mL of 0.1 mol / L dilute hydrochloric acid solution for 3 hours to remove the Na and K elements in the catalyst. The catalyst was then rinsed five times with deionized water and dried in an oven at 100°C for 6 hours to obtain a single-atom Ru / AC catalyst.

[0096] 0.2321 g of bismuth nitrate was dissolved in 5 mL of 0.05 mol / L dilute hydrochloric acid solution to obtain a bismuth precursor solution. The bismuth precursor solution was placed in an acidic burette and dripped dropwise into a rapidly stirred burette containing 10 g of toluene and 3 g of thiamine disulfide compound (C 24 H 34 N8O4S2) in a mixed solution and stirred for 3 h, the bismuth precursor coordinated with the thiamine monomer to form Bi(C 12 H 17 N4O2S) organic ligand, Bi(C 12 H 17 N4O2S) organic ligands are loaded on activated carbon in the form of coordination adsorption and form Ru-Bi(C 12 H 17 N4O2S) / AC, and immediately inject liquid nitrogen to freeze the catalyst, and then vacuum dry it at 0℃ to obtain a single-atom 1%Ru-1%Bi / AC catalyst, the transmission electron microscope image of which is shown in Figure 2. Figure 1 As shown, the high-angle annular dark field scanning transmission electron microscope image of Ru and Bi elements in the catalyst is as follows Figure 2-3 shown.

[0097] 2 g (approximately 4 mL) of the 1% Ru-1% Bi / AC catalyst was weighed and loaded into a micropacked bed reactor. A 10 wt% aqueous solution of 1,4-butynediol was pumped into the reactor via a high-pressure pump at a flow rate of 0.2 mL / min. The conversion of 1,4-butynediol was 98.8%, and the selectivity for 1,4-butanediol was 99.7%.

[0098] Example 2

[0099] Weigh 0.35 g of sodium diethyldithiocarbamate and 0.3 g of furfuryl alcohol and dissolve them in 20 g of dilute hydrochloric acid solution (0.05 mol / L). Add 2.473 mL of RuCl3 solution (0.2 mol / L) dropwise while stirring, and stir at room temperature for 3 h. After stirring, store at room temperature for use.

[0100] Weigh 0.2 g of NaOH and dissolve it in 20 g of water. Use the initial impregnation method to impregnate 10 g of dried activated carbon support. After completion, place the activated carbon in a vacuum drying oven at 50 ° C for 12 h to obtain AC-NaOH.

[0101] The Ru precursor solution was loaded onto the AC-NaOH support by coordination adsorption to form Ru-MOF / AC. Liquid nitrogen was then immediately injected to freeze the catalyst, which was then vacuum dried at 0°C. After vacuum drying, the catalyst was placed in an oven at 100°C for 2 hours to obtain the Ru-MOF / AC catalyst.

[0102] 0.07 g NaCl and 0.02 g KCl were dissolved in 15 g water and then impregnated into the dried catalyst using the initial impregnation method, which was then placed in an oven at 50 °C for 12 h.

[0103] The dried catalyst was placed in a tube furnace and heated to 700°C at a rate of 2°C / min under a nitrogen atmosphere. The temperature was maintained at 700°C for 2 hours before being cooled to room temperature. The catalyst was then immersed in 100 mL of 0.1 mol / L dilute hydrochloric acid solution for 3 hours to remove the Na and K elements in the catalyst. The catalyst was then rinsed five times with deionized water and dried in an oven at 100°C for 6 hours to obtain a single-atom Ru / AC catalyst.

[0104] 0.1161 g of bismuth nitrate was dissolved in 5 mL of 0.05 mol / L dilute hydrochloric acid solution to obtain a bismuth precursor solution. The bismuth precursor solution was placed in an acidic burette and dripped dropwise into a rapidly stirred flask containing 10 g of toluene and 3 g of thiamine disulfide compound (C 24 H 34 N8O4S2) in a mixed solution and stirred for 3 h, the bismuth precursor coordinated with the thiamine monomer to form Bi(C 12 H 17 N4O2S) organic ligand, Bi(C 12 H 17 N4O2S) organic ligands are loaded on activated carbon in the form of coordination adsorption and form Ru-Bi(C 12 H 17N4O2S) / AC, and immediately injecting liquid nitrogen to freeze the catalyst, and then vacuum drying at 0°C to obtain a single-atom 0.5%Ru-0.5%Bi / AC catalyst;

[0105] Weigh 2 g (approximately 4 mL) of the aforementioned 0.5% Ru-0.5% Bi / AC catalyst and load it into a micropacked bed reactor. A 10 wt% aqueous solution of 1,4-butynediol was pumped into the reactor via a high-pressure pump at a flow rate of 0.2 mL / min. The 1,4-butynediol conversion was 100%, and the selectivity for 1,4-butanediol was 99.4%.

[0106] Example 3

[0107] Weigh 0.45 g of sodium diethyldithiocarbamate and 0.4 g of mannitol and dissolve them in 20 g of dilute hydrochloric acid solution (0.05 mol / L). Add 2.528 mL of H2PtCl6 solution (0.2 mol / L) dropwise while stirring, and stir at room temperature for 3 h. After stirring, store at room temperature for use.

[0108] Weigh 0.2 g of NaOH and dissolve it in 20 g of water. Use the initial impregnation method to impregnate 10 g of dried activated carbon support. After completion, place the activated carbon in a vacuum drying oven at 50 ° C for 12 h to obtain AC-NaOH.

[0109] The Pt precursor solution was loaded onto the AC-NaOH support by coordination adsorption to form Pt-MOF / AC. Liquid nitrogen was then immediately injected to freeze the catalyst, which was then vacuum-dried at 0°C. After vacuum drying, the catalyst was placed in an oven at 100°C for 2 hours to obtain the Pt-MOF / AC catalyst.

[0110] 0.07 g NaCl and 0.02 g KCl were dissolved in 15 g water and then impregnated into the dried catalyst using the initial impregnation method, which was then placed in an oven at 50 °C for 12 h.

[0111] The dried catalyst was placed in a tube furnace and heated to 700°C at a rate of 2°C / min under an N2 atmosphere. The temperature was maintained at 700°C for 2 hours before being cooled to room temperature. The catalyst was then immersed in 100 mL of 0.1 mol / L dilute hydrochloric acid solution for 3 hours to remove the Na and K elements. The catalyst was then rinsed five times with deionized water and dried in an oven at 100°C for 6 hours. This yielded a single-atom Pt / AC catalyst.

[0112] 0.2528 g of antimony nitrate (Sb(NO3)3) was dissolved in 5 mL of 0.05 mol / L dilute hydrochloric acid solution to obtain a Sb precursor solution. The Sb precursor solution was placed in an acidic burette and dripped dropwise into a rapidly stirred burette containing 10 g of toluene and 3 g of thiamine disulfide (C 24 H 34 N8O4S2) in a mixed solution and stirred for 3 h, the Sb precursor coordinated with the thiamine monomer to form Sb(C 12 H 17 N4O2S) organic ligand, Sb(C 12 H 17 N4O2S) organic ligands are loaded on activated carbon in the form of coordination adsorption and form Pt-Sb(C 12 H 17 N4O2S) / AC, and immediately inject liquid nitrogen to freeze the catalyst, and then vacuum dry it at 0℃ to obtain a single atomic 1% Pt-1% Sb / AC catalyst, the transmission electron microscopy image of which is shown in Figure 2. Figure 4 As shown;

[0113] 2 g (approximately 4 mL) of the 1% Pt-1% Sb / AC catalyst was weighed and loaded into a micropacked bed reactor. A 10 wt% aqueous solution of 1,4-butynediol was pumped into the reactor via a high-pressure pump at a flow rate of 0.2 mL / min. The conversion of 1,4-butynediol was 99.5%, and the selectivity for 1,4-butanediol was 99.1%.

[0114] Example 4

[0115] Weigh 0.45 g of sodium diethyldithiocarbamate and 0.4 g of mannitol and dissolve them in 20 g of dilute hydrochloric acid solution (0.05 mol / L). Add 2.528 mL of H2PtCl6 solution (0.2 mol / L) dropwise while stirring, and stir at room temperature for 3 h. After stirring, store at room temperature for use.

[0116] Weigh 0.2 g of NaOH and dissolve it in 20 g of water. Use the initial impregnation method to impregnate 10 g of dried activated carbon support. After completion, place the activated carbon in a vacuum drying oven at 50 ° C for 12 h to obtain AC-NaOH.

[0117] The Pt precursor solution was loaded onto the AC-NaOH support by coordination adsorption to form Pt-MOF / AC. Liquid nitrogen was then immediately injected to freeze the catalyst, which was then vacuum-dried at 0°C. After vacuum drying, the catalyst was placed in an oven at 100°C for 2 hours to obtain the Pt-MOF / AC catalyst.

[0118] 0.07 g NaCl and 0.02 g KCl were dissolved in 15 g water and then impregnated into the dried catalyst using the initial impregnation method, which was then placed in an oven at 50 °C for 12 h.

[0119] The dried catalyst was placed in a tube furnace and heated to 700°C at a rate of 2°C / min under a nitrogen atmosphere. The temperature was maintained at 700°C for 2 hours before being cooled to room temperature. The catalyst was then immersed in 100 mL of 0.1 mol / L dilute hydrochloric acid solution for 3 hours to remove the Na and K elements. The catalyst was then rinsed five times with deionized water and dried in an oven at 100°C for 6 hours to obtain a single-atom Pt / AC catalyst.

[0120] 0.2321 g of bismuth nitrate was dissolved in 5 mL of 0.05 mol / L dilute hydrochloric acid solution to obtain a bismuth precursor solution. The dissolved bismuth precursor solution was placed in an acidic burette and dripped dropwise into a rapidly stirred burette containing 10 g of toluene and 3 g of thiamine disulfide compound (C 24 H 34 N8O4S2) in a mixed solution and stirred for 3 h, the Bi precursor coordinated with the thiamine monomer to form Bi(C 12 H 17 N4O2S) organic ligand, Bi(C 12 H 17 N4O2S) organic ligands are loaded on activated carbon in the form of coordination adsorption and form Ru-Bi(C 12 H 17 N4O2S) / AC, and immediately inject liquid nitrogen to freeze the catalyst, and then vacuum dry it at 0°C to obtain a single-atom 1% Pt-1% Bi / AC catalyst;

[0121] 2 g (approximately 4 mL) of the aforementioned 1% Pt-1% Bi / AC catalyst was weighed and loaded into a micropacked bed reactor. A 10 wt% aqueous solution of 1,4-butynediol was pumped into the reactor via a high-pressure pump at a flow rate of 0.2 mL / min. The conversion of 1,4-butynediol was 98.1%, and the selectivity for 1,4-butanediol was 98.8%.

[0122] Example 5

[0123] Weigh 0.35 g of sodium diethyldithiocarbamate and 0.3 g of mannitol and dissolve them in 20 g of dilute hydrochloric acid solution (0.05 mol / L). Add them dropwise to 4.710 mL of PdCl2 solution (0.2 mol / L) while stirring. Stir at room temperature for 3 h. After stirring, store at room temperature until use.

[0124] Weigh 0.2 g of NaOH and dissolve it in 20 g of water. Use the initial impregnation method to impregnate 10 g of dried activated carbon support. After completion, place the activated carbon in a vacuum drying oven at 50 ° C for 12 h to obtain AC-NaOH.

[0125] The Pd precursor solution was loaded onto the AC-NaOH support by coordination adsorption to form Pd-MOF / AC. Liquid nitrogen was then immediately injected to freeze the catalyst, which was then vacuum-dried at 0°C. After vacuum drying, the catalyst was placed in an oven at 100°C for 2 hours to obtain the Pd-MOF / AC catalyst.

[0126] 0.07 g NaCl and 0.02 g KCl were dissolved in 15 g water and then impregnated into the dried catalyst using the initial impregnation method, which was then placed in an oven at 50 °C for 12 h.

[0127] The dried catalyst was placed in a tube furnace and heated to 700°C at a rate of 2°C / min under a nitrogen atmosphere. The temperature was maintained at 700°C for 2 hours before being cooled to room temperature. The catalyst was then immersed in 100 mL of 0.1 mol / L dilute hydrochloric acid solution for 3 hours to remove the Na and K elements. The catalyst was then rinsed five times with deionized water and dried in an oven at 100°C for 6 hours to obtain a single-atom Pd / AC catalyst.

[0128] 0.2321 g of antimony nitrate (Sb(NO3)3) was dissolved in 5 mL of 0.05 mol / L dilute hydrochloric acid solution to obtain a Sb precursor solution. The bismuth precursor solution was placed in an acidic burette and dripped dropwise into a rapidly stirred burette containing 10 g of toluene and 3 g of thiamine disulfide (C 24 H 34 N8O4S2) in a mixed solution and stirred for 3 h, the Sb precursor coordinated with the thiamine monomer to form Sb(C 12 H 17 N4O2S) organic ligand, Sb(C 12 H 17 N4O2S) organic ligands are loaded on activated carbon in the form of coordination adsorption and form Pd-Sb(C 12 H 17 N4O2S) / AC, and immediately injecting liquid nitrogen to freeze the catalyst, and then vacuum drying at 0°C to obtain a single atomic 1% Pd-1% Sb / AC catalyst;

[0129] 2 g (approximately 4 mL) of the 1% Pd-1% Sb / AC catalyst was weighed and loaded into a micropacked bed reactor. A 10 wt% aqueous solution of 1,4-butynediol was pumped into the reactor via a high-pressure pump at a flow rate of 0.2 mL / min. The conversion of 1,4-butynediol was 100%, and the selectivity for 1,4-butanediol was 99.3%.

[0130] Example 6

[0131] Weigh 0.25 g of sodium diethyldithiocarbamate and 0.5 g of furfuryl alcohol and dissolve them in 20 g of dilute hydrochloric acid solution (0.05 mol / L). Add 4.710 mL of PdCl2 solution (0.2 mol / L) dropwise while stirring, and stir at room temperature for 3 h. After stirring, store at room temperature for use.

[0132] Weigh 0.2 g of NaOH and dissolve it in 20 g of water. Use the initial impregnation method to impregnate 10 g of dried activated carbon support. After completion, place the activated carbon in a vacuum drying oven at 50 ° C for 12 h to obtain AC-NaOH.

[0133] The Pd precursor solution was loaded onto the AC-NaOH support by coordination adsorption to form Pd-MOF / AC. Liquid nitrogen was then immediately injected to freeze the catalyst, which was then vacuum-dried at 0°C. After vacuum drying, the catalyst was placed in an oven at 100°C for 2 hours to obtain the Pd-MOF / AC catalyst.

[0134] Weigh 0.07g NaCl and 0.02g KCl and dissolve them in 15g water. Then use the initial impregnation method to impregnate the dried catalyst, and then place it in a 50℃ oven for 12h. Place the dried catalyst in a tube furnace and heat it to 700℃ at a heating rate of 2℃ / min under N2 atmosphere. Keep it at 700℃ for 2h and then cool it to room temperature. Pour the catalyst into 100mL of 0.1mol / L dilute hydrochloric acid solution and soak it for 3h to remove Na and K elements in the catalyst. Then wash it with deionized water 5 times. After washing, place the catalyst in a 100℃ oven and dry it for 6h to obtain a single-atom Pd / AC catalyst.

[0135] 0.2321 g of bismuth nitrate was dissolved in 5 mL of 0.05 mol / L dilute hydrochloric acid solution to obtain a bismuth precursor solution. The dissolved bismuth precursor solution was placed in an acidic burette and dripped dropwise into a rapidly stirred burette containing 10 g of toluene and 3 g of thiamine disulfide compound (C 24 H 34 N8O4S2) in a mixed solution and stirred for 3 h, the Bi precursor coordinated with the thiamine monomer to form Bi(C 12 H 17N4O2S) organic ligand, Bi(C 12 H 17 N4O2S) organic ligands are loaded on activated carbon in the form of coordination adsorption and form Ru-Bi(C 12 H 17 N4O2S) / AC, and immediately injecting liquid nitrogen to freeze the catalyst, and then vacuum drying at 0°C to obtain a single atomic 1% Pd-1% Bi / AC catalyst;

[0136] 2 g (approximately 4 mL) of the 1% Pd-1% Bi / AC catalyst was weighed and loaded into a micropacked bed reactor. A 10 wt% aqueous solution of 1,4-butynediol was pumped into the reactor via a high-pressure pump at a flow rate of 0.2 mL / min. The conversion of 1,4-butynediol was 99.7%, and the selectivity for 1,4-butanediol was 98.9%.

[0137] Example 7

[0138] Weigh 0.25 g of sodium diethyldithiocarbamate and 0.5 g of furfuryl alcohol and dissolve them in 20 g of dilute hydrochloric acid solution (0.05 mol / L). Add 4.710 mL of PdCl2 solution (0.2 mol / L) dropwise while stirring, and stir at room temperature for 3 h. After stirring, store at room temperature for use.

[0139] Weigh 0.2 g of NaOH and dissolve it in 20 g of water. Use the initial impregnation method to impregnate 10 g of dried activated carbon support. After completion, place the activated carbon in a vacuum drying oven at 50 ° C for 12 h to obtain AC-NaOH.

[0140] The Pd precursor solution was loaded onto the AC-NaOH support by coordination adsorption to form Pd-MOF / AC. Liquid nitrogen was then immediately injected to freeze the catalyst, which was then vacuum dried at 0°C. After vacuum drying, the catalyst was placed in an oven at 100°C for 2 hours to obtain the Pd-MOF / AC catalyst.

[0141] 0.07g of NaCl and 0.02g of KCl were weighed and dissolved in 15g of water. The catalyst was then impregnated into the dried catalyst using the initial impregnation method and then dried in a 50°C oven for 12 hours. The dried catalyst was placed in a tube furnace and heated to 700°C at a rate of 2°C / min under a nitrogen atmosphere. The temperature was maintained at 700°C for 2 hours before being cooled to room temperature. The catalyst was then immersed in 100mL of 0.1mol / L dilute hydrochloric acid solution for 3 hours to remove the Na and K elements. The catalyst was then rinsed five times with deionized water and dried in a 100°C oven for 6 hours to obtain a single-atom Pd / AC catalyst.

[0142] 0.1161 g of antimony nitrate (Sb(NO3)3) was dissolved in 5 mL of 0.05 mol / L dilute hydrochloric acid solution to obtain a Sb precursor solution. The bismuth precursor solution was placed in an acidic burette and dripped dropwise into a rapidly stirred burette containing 10 g of toluene and 3 g of thiamine disulfide (C 24 H 34 N8O4S2) in a mixed solution and stirred for 3 h, the Sb precursor coordinated with the thiamine monomer to form Sb(C 12 H 17 N4O2S) organic ligand, Sb(C 12 H 17 N4O2S) organic ligands are loaded on activated carbon in the form of coordination adsorption and form Pd-Sb(C 12 H 17 N4O2S) / AC, and immediately injecting liquid nitrogen to freeze the catalyst, and then vacuum drying at 0°C to obtain a single atomic 1% Pd-0.5% Sb / AC catalyst;

[0143] 2 g (approximately 4 mL) of the aforementioned 1% Pd-0.5% Sb / AC catalyst was weighed and loaded into a micropacked bed reactor. A 10 wt% aqueous solution of 1,4-butynediol was pumped into the reactor via a high-pressure pump at a flow rate of 0.2 mL / min. The conversion of 1,4-butynediol was 100%, and the selectivity for 1,4-butanediol was 97.7%.

[0144] Comparative Example 1

[0145] Weigh 0.25 g of sodium diethyldithiocarbamate and 0.5 g of furfuryl alcohol and dissolve them in 20 g of dilute hydrochloric acid solution (0.05 mol / L). Add 4.945 mL of RuCl3 solution (0.2 mol / L) dropwise while stirring, and stir at room temperature for 3 h. After stirring, store at room temperature for use.

[0146] Weigh 0.2 g of NaOH and dissolve it in 20 g of water. Use the initial impregnation method to impregnate 10 g of dried activated carbon support. After completion, place the activated carbon in a vacuum drying oven at 50 ° C for 12 h to obtain AC-NaOH.

[0147] The Ru precursor solution was loaded onto the AC-NaOH support by coordination adsorption to form Ru-MOF / AC. Liquid nitrogen was then immediately injected to freeze the catalyst, which was then vacuum dried at 0°C. After vacuum drying, the catalyst was placed in an oven at 100°C for 2 hours to obtain the Ru-MOF / AC catalyst.

[0148] Weigh 0.07g NaCl and 0.02g KCl and dissolve them in 15g water. Then use the initial impregnation method to impregnate the dried catalyst, and then place it in a 50℃ oven for 12h. Place the dried catalyst in a tube furnace, heat it to 700℃ at a heating rate of 2℃ / min under N2 atmosphere, and keep it at 700℃ for 2h before cooling it to room temperature. Pour the catalyst into 100mL of 0.1mol / L dilute hydrochloric acid solution and soak it for 3h to remove Na and K elements in the catalyst, then wash it with deionized water 5 times. After washing, place the catalyst in a 100℃ oven and dry it for 6h to obtain a single atomic 1%Ru / AC catalyst;

[0149] 2 g (approximately 4 mL) of the 1% Ru / AC catalyst was weighed and loaded into a micropacked bed reactor. A 10 wt% aqueous 1,4-butynediol solution was pumped into the reactor via a high-pressure pump at a flow rate of 0.2 mL / min. The 1,4-butynediol conversion was 95.1%, and the selectivity for 1,4-butanediol was 82.7%.

[0150] Comparative Example 2

[0151] Weigh 0.25 g of sodium diethyldithiocarbamate and 0.5 g of furfuryl alcohol and dissolve them in 20 g of dilute hydrochloric acid solution (0.05 mol / L). Add 2.473 mL of RuCl3 solution (0.2 mol / L) dropwise while stirring, and stir at room temperature for 3 h. After stirring, store at room temperature for use.

[0152] Weigh 0.2 g of NaOH and dissolve it in 20 g of water. Use the initial impregnation method to impregnate 10 g of dried activated carbon support. After completion, place the activated carbon in a vacuum drying oven at 50 ° C for 12 h to obtain AC-NaOH.

[0153] After drying, the Ru precursor solution was loaded onto the AC-NaOH support by coordination adsorption to form Ru-MOF / AC. Liquid nitrogen was then immediately injected to freeze the catalyst, which was then vacuum-dried at 0°C. After vacuum drying, the catalyst was placed in an oven at 100°C and dried for 2 hours to obtain the Ru-MOF / AC catalyst.

[0154] 0.07g of NaCl and 0.02g of KCl were weighed and dissolved in 15g of water. The catalyst was then impregnated into the dried catalyst using the initial impregnation method and then dried in a 50°C oven for 12 hours. The dried catalyst was placed in a tube furnace and heated to 700°C at a rate of 2°C / min under a nitrogen atmosphere. The temperature was maintained at 700°C for 2 hours before being cooled to room temperature. The catalyst was then immersed in 100mL of 0.1mol / L dilute hydrochloric acid solution for 3 hours to remove the Na and K elements. The catalyst was then rinsed five times with deionized water and dried in a 100°C oven for 6 hours to obtain a single-atom 0.5% Ru / AC catalyst.

[0155] 2 g (approximately 4 mL) of the aforementioned 0.5% Ru / AC catalyst was weighed and loaded into a micropacked bed reactor. A 10 wt% aqueous solution of 1,4-butynediol was pumped into the reactor via a high-pressure pump at a flow rate of 0.2 mL / min. The conversion of 1,4-butynediol was 86.4%, and the selectivity for 1,4-butanediol was 79.3%.

[0156] Comparative Example 3

[0157] 0.25 g of sodium diethyldithiocarbamate and 0.5 g of furfuryl alcohol were dissolved in 20 g of dilute hydrochloric acid solution (0.05 mol / L), and 2.355 mL of PdCl2 solution (0.2 mol / L) was added dropwise while stirring. The mixture was stirred at room temperature for 3 h. After stirring, it was stored at room temperature for use.

[0158] Weigh 0.2 g of NaOH and dissolve it in 20 g of water. Use the initial impregnation method to impregnate 10 g of dried activated carbon support. After completion, place the activated carbon in a vacuum drying oven at 50 ° C for 12 h to obtain AC-NaOH.

[0159] After drying, the Pd precursor solution was loaded onto the AC-NaOH support by coordination adsorption to form Pd-MOF / AC. Liquid nitrogen was then immediately injected to freeze the catalyst, which was then vacuum-dried at 0°C. After vacuum drying, the catalyst was placed in an oven at 100°C and dried for 2 hours to obtain the Pd-MOF / AC catalyst.

[0160] 0.07g of NaCl and 0.02g of KCl were weighed and dissolved in 15g of water. The catalyst was then impregnated into the dried catalyst using the initial impregnation method and then dried in a 50°C oven for 12 hours. The dried catalyst was placed in a tube furnace and heated to 700°C at a rate of 2°C / min under a nitrogen atmosphere. The temperature was maintained at 700°C for 2 hours before being cooled to room temperature. The catalyst was then immersed in 100mL of 0.1mol / L dilute hydrochloric acid solution for 3 hours to remove the Na and K elements. The catalyst was then rinsed five times with deionized water and dried in a 100°C oven for 6 hours to obtain a single-atom 0.5% Pd / AC catalyst.

[0161] 2 g (approximately 4 mL) of the aforementioned 0.5% Pd / AC catalyst was weighed and loaded into a micropacked bed reactor. A 10 wt% aqueous solution of 1,4-butynediol was pumped into the reactor via a high-pressure pump at a flow rate of 0.2 mL / min. The conversion of 1,4-butynediol was 88.9%, and the selectivity for 1,4-butanediol was 73.1%.

[0162] Comparative Example 4

[0163] Weigh 4.945 mL of 0.2 mol / L RuCl3 and dissolve it in 20 g of deionized water;

[0164] Weigh 0.2 g of NaOH and dissolve it in 20 g of water. Use the initial impregnation method to impregnate 10 g of dried activated carbon support, and then place it in a 50 ° C oven for 12 h to obtain AC-NaOH.

[0165] 10g of AC-NaOH support after drying was placed in a polytetrafluoroethylene boat. The Ru precursor solution was impregnated into the activated carbon using the initial impregnation method to form Ru / AC-NaOH. Liquid nitrogen was immediately injected after impregnation to freeze the catalyst. The catalyst was then vacuum dried at 0°C. After vacuum drying, the catalyst was placed in a 100°C oven and dried for 2 hours to obtain a 1% Ru / AC single-atom catalyst.

[0166] 2 g (approximately 4 mL) of the 1% Ru / AC catalyst was weighed and loaded into a micropacked bed reactor. A 10 wt% aqueous 1,4-butynediol solution was pumped into the reactor via a high-pressure pump at a flow rate of 0.2 mL / min. The conversion of 1,4-butynediol was 67.8%, and the selectivity for 1,4-butanediol was 83.9%.

[0167] Comparative Example 5

[0168] Weigh 0.2 g of NaOH and dissolve it in 20 g of water. Use the initial impregnation method to impregnate 10 g of dried activated carbon support. After completion, place the activated carbon in a vacuum drying oven at 50 ° C for 12 h to obtain AC-NaOH.

[0169] 0.2321 g of bismuth nitrate was dissolved in 5 mL of 0.05 mol / L dilute hydrochloric acid solution to obtain a bismuth precursor solution. The bismuth precursor solution was placed in an acidic burette and dripped dropwise into a rapidly stirred burette containing 10 g of toluene and 3 g of thiamine disulfide compound (C 24 H 34 N8O4S2) in a mixed solution and stirred for 3 h, the bismuth precursor coordinated with the thiamine monomer to form Bi(C 12 H 17 N4O2S) organic ligand, Bi(C 12 H 17 N4O2S) organic ligands are loaded on activated carbon in the form of coordination adsorption and form Bi(C 12 H 17 N4O2S) / AC, and immediately inject liquid nitrogen to freeze the catalyst, and then vacuum dry it at 0°C to obtain a single-atom 1% Bi / AC catalyst;

[0170] 2g (approximately 4mL) of the 1% Bi / AC catalyst was weighed and loaded into a micropacked bed reactor. A 10wt% aqueous 1,4-butynediol solution was pumped into the reactor via a high-pressure pump at a flow rate of 0.2mL / min. The conversion of 1,4-butynediol was 0.6%. These results indicate that Bi alone has little catalytic activity when loaded on activated carbon. It is only when Bi is alloyed with a noble metal and loaded on the activated carbon surface that catalytic activity and selectivity are enhanced.

[0171] Comparative Example 6

[0172] Weigh 0.2 g of NaOH and dissolve it in 20 g of water. Use the initial impregnation method to impregnate 10 g of dried activated carbon support. After completion, place the activated carbon in a vacuum drying oven at 50 ° C for 12 h to obtain AC-NaOH.

[0173] 0.2528 g of antimony nitrate (Sb(NO3)3) was dissolved in 5 mL of 0.05 mol / L dilute hydrochloric acid solution to obtain a Sb precursor solution. The Sb precursor solution was placed in an acidic burette and dripped dropwise into a rapidly stirred burette containing 10 g of toluene and 3 g of thiamine disulfide (C 24 H 34 N8O4S2) in a mixed solution and stirred for 3 h, the Sb precursor coordinated with the thiamine monomer to form Sb(C 12 H 17 N4O2S) organic ligand, Sb(C 12 H 17 N4O2S) organic ligands are loaded on activated carbon in the form of coordination adsorption and form Sb(C 12 H 17N4O2S) / AC, and immediately inject liquid nitrogen to freeze the catalyst, and then vacuum dry it at 0℃ to obtain a single atomic 1% Sb / AC catalyst, the transmission electron microscope image of which is shown in Figure 4 As shown;

[0174] 2g (approximately 4mL) of the 1% Sb / AC catalyst was weighed and loaded into a micropacked bed reactor. A 10wt% aqueous 1,4-butynediol solution was pumped into the reactor via a high-pressure pump at a flow rate of 0.2mL / min. The conversion of 1,4-butynediol was 0.2%. These results indicate that Sb alone, when loaded on activated carbon, has little catalytic activity. However, Sb, when combined with a noble metal to form an alloy catalyst and loaded on the activated carbon surface, enhances catalytic activity and selectivity.

[0175] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0176] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A single-atom alloy catalyst, characterized in that The support of the single-atom alloy catalyst includes a porous carbon material, and the active component includes a noble metal M and a heavy metal N. The noble metal M includes at least one of Ru, Pt or Pd, and the heavy metal N includes at least one of Bi or Sb.

2. The single-atom alloy catalyst according to claim 1, characterized in that The mass proportion of the noble metal M in the single-atom alloy catalyst is 0.2%-1.5%, and the mass proportion of the heavy metal N is 0.1%-1%; Optionally, the carrier is a carrier activated by an alkaline substance, and the mass proportion of the alkaline substance in the carrier is 0.05%-1%.

3. A method for preparing the single-atom alloy catalyst according to claim 1 or 2, characterized in that: The method comprises: preparing a solution comprising a first complexing agent and an alcohol compound, and adding a noble metal M precursor to obtain an M precursor complex solution; Adding the M precursor complex solution to the support, and performing freeze-drying treatment to obtain a first intermediate of the single-atom alloy catalyst; The first intermediate of the single-atom alloy catalyst is immersed in a metal salt solution, and a second intermediate of the single-atom alloy catalyst is obtained by drying and calcining. dissolving the single-atom alloy catalyst second intermediate in an acidic solution to obtain a single-atom alloy catalyst third intermediate; A solution containing a heavy metal N precursor is prepared, the solution is mixed with a second complexing agent to obtain a N precursor complex solution, the N precursor complex solution is added to the single atom alloy catalyst third intermediate, and the single atom alloy catalyst is obtained by freeze-drying.

4. The method according to claim 3, characterized in that The first complexing agent includes diethyldithiocarbamate; Optionally, the alcohol compound comprises at least one of inositol, tryptophan, mannitol or furfuryl alcohol; Optionally, the noble metal M precursor includes at least one of a Ru precursor, a Pt precursor, and a Pd precursor; The Ru precursor includes at least one of ruthenium trichloride, ruthenium nitrate, ruthenium ammonium chloride or ruthenium acetate; The Pt precursor includes at least one of chloroplatinic acid, tetraammineplatinum dichloride, diethanolamine hexahydroxyplatinate or platinum nitrate; The Pd precursor includes at least one of palladium dichloride, palladium nitrate, palladium hydroxide or palladium sulfate.

5. The method according to claim 3, characterized in that The carrier is an activated carrier, and the activation treatment includes impregnating the carrier with an alkaline solution.

6. The method according to claim 3, characterized in that The M precursor complex solution is added to the carrier at 0-5°C.

7. The method according to claim 3, characterized in that The metal salt in the metal salt solution includes sodium chloride and potassium chloride, and the mass ratio of sodium chloride to potassium chloride in the metal salt solution is (1-5):1; Optionally, the calcination treatment is performed at a temperature of 600-800° C. and for a time of 1-4 hours.

8. The method according to claim 3, characterized in that The heavy metal N precursor includes at least one of a Bi precursor or a Sb precursor; the Bi precursor includes at least one of bismuth chloride, bismuth vanadate, bismuth nitrate, bismuth bromide or bismuth iodate; the Sb precursor includes at least one of antimony nitrate, antimony sulfate, antimony trichloride, antimony nitride, antimony carbonate, antimony bromide or antimony sulfide; Optionally, the second complexing agent comprises C 24 H 34 N8O4S2.

9. Use of the single-atom alloy catalyst according to claim 1 or 2 or the single-atom alloy catalyst obtained according to the method according to any one of claims 3 to 8 in the preparation of 1,4-butanediol by hydrogenation of 1,4-butynediol.

10. A method for preparing 1,4-butanediol by hydrogenating 1,4-butynediol, characterized in that: The method comprises: using a single-atom alloy catalyst to catalyze the hydrogenation of 1,4-butynediol to prepare 1,4-butanediol; The single-atom alloy catalyst is the single-atom alloy catalyst according to claim 1 or 2, or the single-atom alloy catalyst obtained by the method according to any one of claims 3 to 8; Optionally, the temperature for preparing 1,4-butene diol by hydrogenation of 1,4-butynediol is 20-200° C. and the pressure is 0.1-15 MPa.

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