Oxygen vacancy-enriched Co-based supported catalyst, preparation method and application thereof in preparation of mixed enol from synthesis gas

Abstract

The invention provides an oxygen-vacancy-rich Co-based supported catalyst, a preparation method and application of the oxygen-vacancy-rich Co-based supported catalyst in preparation of mixed enol from synthesis gas, and the preparation method comprises the following steps: S1, providing a reducing carrier, and pretreating the reducing carrier; s2, preparing a Co-based metal salt solution, and impregnating the reducing carrier in the Co-based metal salt solution by adopting an excessive impregnation method to obtain a catalyst precursor solution; and S3, drying the catalyst precursor solution, roasting, grinding, tabletting and sieving to obtain the Co-based supported catalyst. The reducing carrier is impregnated in the Co-based metal salt solution through an excessive impregnation method, the Co-based supported catalyst rich in oxygen vacancies is obtained through roasting, the preparation method is simple, the stoichiometry is controllable, synthesis equipment is simple, the cost of raw materials is low, and the prepared Co-based supported catalyst rich in oxygen vacancies has high catalytic activity in a reaction for preparing mixed enol from synthesis gas, and has good application prospects. Higher catalytic activity and target product selectivity are realized.

Description

Technical Field

[0001] The invention belongs to the technical field of catalyst preparation, and particularly relates to a Co-based supported catalyst rich in oxygen vacancies, a preparation method and application thereof in preparing mixed enols from synthesis gas. Background Art

[0002] Supported metal catalysts are widely used due to their high efficiency and cost-effectiveness in industrial catalytic reactions. In particular, Co-based catalysts have become a hot topic of research due to their activity and selectivity in a variety of chemical reactions. However, the reduction process of Co-based catalysts has certain limitations, which restricts their performance in reactions such as synthesis gas to mixed alkenes / alcohols. Traditional Co-based catalysts face two main stages in the reduction process: Co 2+ Reduction to Co δ+ Relatively easy, but Co δ+ Further reduction to Co 0 This difficulty is mainly attributed to the strong interaction between the metal and the carrier, which causes the metal nanoparticles to be covered by the reduced carrier, thus affecting the accessibility of the active sites of the catalyst and the catalytic efficiency.

[0003] Oxygen vacancies, as an important anion defect, have been shown to significantly affect the reducibility and catalytic performance of catalysts. The presence of oxygen vacancies can capture overflow oxygen in oxygen-containing species, thereby enhancing the reducibility of catalysts. In addition, oxygen vacancies can promote CO dissociation and adsorption to form carbonate species and surface carbon species, which is crucial for reactions such as syngas conversion. The porous cobalt oxide nanolaminate structure shows excellent catalytic performance due to its high specific surface area and abundant oxygen vacancies. This structure not only provides more active sites, but also promotes the exchange of intermediate species and electron transfer, thereby improving the catalytic efficiency.

[0004] In view of the limitations of existing Co-based catalysts in the reduction process and the positive effect of oxygen vacancies on catalytic performance, it is necessary to provide a Co-based supported catalyst rich in oxygen vacancies in order to achieve high catalytic activity and target product selectivity in reactions such as synthesis gas to mixed olefins / alcohols. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, the object of the present invention is to provide a Co-based supported catalyst rich in oxygen vacancies, a preparation method and its application in the preparation of mixed enols from synthesis gas, so as to achieve higher catalytic activity and target product selectivity.

[0006] To achieve the above object and other related objects, the present invention provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies, the preparation method comprising the following steps:

[0007] S1, providing a reducing carrier, and pretreating the reducing carrier;

[0008] S2, preparing a Co-based metal salt solution, and impregnating the reducing carrier into the Co-based metal salt solution by an excess impregnation method to obtain a catalyst precursor solution;

[0009] S3, drying the catalyst precursor liquid, then calcining it, and then grinding, tableting, and sieving it to obtain a Co-based supported catalyst precursor;

[0010] S4, subjecting the Co-based supported catalyst precursor to reduction treatment and carbonization treatment to obtain a Co-supported catalyst rich in oxygen vacancies.

[0011] Preferably, the reducing carrier in step S1 includes one or a combination of TiO2, CeO2, ZrO2, MoO3, WO3, V2O3, and MnO2.

[0012] Preferably, the pretreatment in step S1 is specifically drying the reducing carrier, wherein the drying is performed at 50 to 120° C. for 12 to 24 hours.

[0013] Preferably, the Co source in the Co-based metal salt solution in step S2 includes one or a combination of cobalt nitrate, cobalt chloride, cobalt oxalate, cobalt acetate and cobalt sulfate.

[0014] Preferably, in step S2, the mass percentage between the Co element in the Co-based metal salt solution and the reducing carrier is 5% to 50%.

[0015] Preferably, the volume of the Co-based metal salt solution in step S2 is 2 to 10 times the theoretical water absorption capacity of the reducing carrier.

[0016] Preferably, before drying the catalyst precursor liquid after impregnation in step S3, a rotary evaporation step is also included. Specifically, the rotary evaporation is to use a rotary evaporator to rotary evaporate the catalyst precursor liquid after impregnation under vacuum to obtain a solid precursor.

[0017] Preferably, the drying temperature in step S3 is 50-120° C., and the drying time is 12-24 hours.

[0018] Preferably, the calcination temperature in step S3 is 300-600° C., and the calcination time is 4-10 hours.

[0019] Preferably, the reducing atmosphere of the reduction treatment in step S4 is pure H2 or H2 / Ar mixed gas, the reduction temperature is 300-500°C, and the reduction time is 5-10h.

[0020] Preferably, the carbonization atmosphere of the carbonization treatment in step S4 is pure CO or synthesis gas with a H2 / CO molar ratio of 0.5 to 2.0, the carbonization pressure is 0.1 to 1 MPa, and the carbonization time is 5 to 24 hours.

[0021] Preferably, the particle size of the Co-based supported catalyst in step S4 is 20-80 meshes.

[0022] The present invention also provides a Co-based supported catalyst rich in oxygen vacancies, wherein the Co-based supported catalyst is prepared by adopting the preparation method of the Co-based supported catalyst rich in oxygen vacancies.

[0023] The present invention also provides an application of a Co-based supported catalyst rich in oxygen vacancies in a reaction of preparing mixed enols from synthesis gas. The Co-based supported catalyst is prepared by the above-mentioned preparation method.

[0024] Preferably, the molar ratio of H2 to CO in the feed gas is 0.5 to 2.0, and the space velocity of the feed gas is 500 to 10000 mL g Cat. -1 h -1 .

[0025] Preferably, the reaction temperature is 200-300° C., and the reaction pressure is 0.5-6.0 MPa.

[0026] As described above, the oxygen vacancy-rich Co-based supported catalyst, preparation method and application thereof in preparing mixed enols from synthesis gas of the present invention have the following beneficial effects:

[0027] The present invention impregnates a reducing carrier into a Co-based metal salt solution by an excess impregnation method, and obtains a Co-based supported catalyst rich in oxygen vacancies through calcination. The preparation method is simple, the synthesis equipment is simple, the raw material cost is low, and it is easy to scale up for industrial application. The mass proportion of the Co element in the prepared Co-based supported catalyst rich in oxygen vacancies is precisely controllable, and the reducing carrier is partially reduced to generate oxygen vacancy active sites, which not only directly increases the active sites of the catalyst, but also regulates the physical phase composition of the Co element, further promotes the catalytic performance of the Co component, and strengthens the catalytic performance of the synthesis gas to mixed enol reaction, thereby achieving higher catalytic activity and target product selectivity. DETAILED DESCRIPTION

[0028] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0029] Before further describing the specific embodiments of the present invention, it should be understood that the scope of protection of the present invention is not limited to the specific embodiments described below; it should also be understood that the terms used in the examples of the present invention are intended to describe specific embodiments, rather than to limit the scope of protection of the present invention. The test methods in the following examples without specifying specific conditions are generally carried out under conventional conditions or under conditions recommended by the manufacturers.

[0030] When the embodiments give numerical ranges, it should be understood that, unless otherwise specified in the present invention, both endpoints of each numerical range and any numerical value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as those generally understood by those skilled in the art. In addition to the specific methods, equipment, and materials used in the embodiments, according to the grasp of the prior art by those skilled in the art and the record of the present invention, any methods, equipment, and materials of the prior art similar or equivalent to the methods, equipment, and materials described in the embodiments of the present invention can also be used to realize the present invention.

[0031] The present invention provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies, the preparation method comprising the following steps:

[0032] S1, providing a reducing carrier, and pretreating the reducing carrier;

[0033] S2, preparing a Co-based metal salt solution, and impregnating the reducing carrier into the Co-based metal salt solution by an excess impregnation method to obtain a catalyst precursor solution;

[0034] S3, drying the catalyst precursor liquid, then calcining it, and then grinding, tableting, and sieving it to obtain a Co-based supported catalyst precursor;

[0035] S4. The Co-based supported catalyst precursor is subjected to reduction treatment and carbonization treatment to obtain a Co-supported catalyst rich in oxygen vacancies.

[0036] Specifically, during the catalyst reduction process, the reducing carrier itself will be partially reduced, thereby generating oxygen vacancy active sites, which have certain performance in preparing mixed enols from synthesis gas. At the same time, the oxygen vacancy active sites can further promote the catalytic performance of the Co component; cobalt oxide is loaded on the reducing carrier, and the cobalt oxide in the carrier has good dispersibility, more favorable energy and isomorphous substitution characteristics, which helps to reduce oxygen formation energy and activation energy.

[0037] As an example, the reducing carrier in step S1 includes one or a combination of TiO2, CeO2, ZrO2, MoO3, WO3, V2O3, and MnO2.

[0038] In a specific embodiment of the present invention, the carrier used is a reducing carrier. During the catalyst reduction process, the reducing carrier will be partially reduced, thereby generating certain oxygen vacancy active sites. In a specific embodiment of the present invention, the reducing carrier can be a commercial product on sale, or can be obtained through chemical synthesis.

[0039] As an example, the pretreatment in step S1 is specifically to dry the reducing carrier, wherein the drying is performed at 50 to 120° C. for 12 to 24 hours.

[0040] Specifically, the drying temperature of the reducing carrier may include any value within the range of 50°C, 60°C, 80°C, 100°C, 120°C, etc., and the drying time may include any value within the range of 12h, 14h, 16h, 18h, 20h, 22h, 24h, etc. Preferably, the drying condition is drying at 120°C for 24h.

[0041] As an example, the Co source in the Co-based metal salt solution in step S2 includes one or a combination of cobalt nitrate, cobalt chloride, cobalt oxalate, cobalt acetate, and cobalt sulfate.

[0042] As an example, the mass percentage between the Co element and the reducing carrier in the Co-based metal salt solution in step S2 is 5% to 50%.

[0043] Specifically, the mass percentage between the Co element in the Co-based metal salt solution and the reducing carrier may include a value in any range of 5, 10, 20, 30, 40, 50, etc. Preferably, the mass percentage between the Co element in the Co-based metal salt solution and the reducing carrier is 20% to 30%.

[0044] As an example, the volume of the Co-based metal salt solution in step S2 is 2 to 10 times (eg, 2 times, 4 times, 6 times, 8 times, 10 times, etc.) the theoretical water absorption capacity of the reducing carrier.

[0045] Preferably, the volume of the Co-based metal salt solution is 5 to 10 times the theoretical water absorption capacity of the reducing carrier.

[0046] As an example, before drying the catalyst precursor liquid after impregnation in step S3, a rotary evaporation step is also included. The rotary evaporation is specifically to use a rotary evaporator to rotary evaporate the catalyst precursor liquid after impregnation under vacuum to obtain a solid precursor.

[0047] Specifically, the gas pressure conditions of rotary evaporation are preferably -0.1 MPa and the temperature is 60°C.

[0048] As an example, in step S3, the drying temperature is 50-120° C., and the drying time is 12-24 hours.

[0049] Specifically, the drying temperature may include values ​​within any range such as 50°C, 60°C, 80°C, 100°C, 120°C, etc., and the drying time may include values ​​within any range such as 12h, 14h, 16h, 18h, 20h, 22h, 24h, etc. Preferably, the drying condition is drying at 120°C for 24h.

[0050] As an example, the calcination temperature in step S3 is 300-600° C., and the calcination time is 4-10 hours.

[0051] Specifically, the calcination temperature may include values ​​within any range such as 300°C, 400°C, 500°C, 600°C, etc., and the calcination time may include values ​​within any range such as 4h, 5h, 6h, 7h, 8h, 9h, 10h, etc. Preferably, the calcination temperature is 400°C and the calcination time is 5h.

[0052] As an example, the reducing atmosphere of the reduction treatment in step S4 is pure H2 or H2 / Ar mixed gas, the reduction temperature is 300-500°C, and the reduction time is 5-10 hours.

[0053] Specifically, the reduction temperature and time directly affect the reduction degree of the Co element, and the reducing carrier will be partially reduced during the reduction process, thereby generating certain oxygen vacancy active sites, further promoting the catalytic performance of the Co component; the reduction temperature may include values ​​within any range of 300°C, 350°C, 400°C, 450°C, 500°C, etc., and the reduction time may include values ​​within any range of 5h, 6h, 7h, 8h, 9h, 10h, etc.

[0054] As an example, the carbonization atmosphere for the carbonization treatment in step S4 is pure CO or synthesis gas with a H2 / CO molar ratio of 0.5 to 2.0 (such as 0.5, 1, 1.5, 2, etc.), the carbonization pressure is 0.1 to 1 MPa, and the carbonization time is 5 to 24 hours.

[0055] Specifically, the carbonization conditions directly affect the ratio of the two phases of Co and Co2C in the catalyst, and thus affect the activity of the catalyst and the composition of the distribution of the reaction products in the syngas mixed ene alcohol reaction. The carbonization pressure may include values ​​within any range such as normal pressure, 0.2 MPa, 0.4 MPa, 0.6 MPa, 0.8 MPa, 1 MPa, etc., and the carbonization time may include values ​​within any range such as 5 h, 8 h, 10 h, 12 h, 15 h, 18 h, 20 h, 22 h, 24 h, etc.

[0056] Preferably, the reduction treatment is reduction at 400° C. for 5 h in a pure H 2 atmosphere, and the carbonization treatment is carbonization at normal pressure for 10 h in a pure CO atmosphere.

[0057] As an example, the particle size of the Co-based supported catalyst in step S4 is 20-80 meshes.

[0058] Preferably, the particle size of the Co-based supported catalyst is 40 to 60 meshes.

[0059] The present invention also provides a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst is prepared by adopting the preparation method of the Co-based supported catalyst rich in oxygen vacancies.

[0060] The present invention also provides an application of a Co-based supported catalyst rich in oxygen vacancies in a reaction of preparing mixed enols from synthesis gas. The Co-based supported catalyst is prepared by the above-mentioned preparation method.

[0061] As an example, the molar ratio of H2 to CO in the feed gas is 0.5 to 2.0, and the space velocity of the feed gas is 500 to 10000 mL g Cat. -1 h -1 .

[0062] Specifically, the molar ratio of H2 to CO in the feed gas may include any value in the range of 0.5, 1, 1.5, 2, etc., and the space velocity of the feed gas may include 500 mL g Cat. -1 h -1 , 1000mL g Cat. -1 h -1 、3000mL g Cat. -1 h -1 , 5000mL g Cat. -1 h -1 , 8000mL g Cat. -1 h -1 , 10000mL g Cat. -1 h -1 Preferably, the molar ratio of H2 to CO in the feed gas is 2, and the feed gas space velocity is 1000-2000 mL g Cat. -1 h -1 .

[0063] As an example, the reaction temperature is 200-300° C., and the reaction pressure is 0.5-6.0 MPa.

[0064] Specifically, the reaction temperature may include values ​​in any range of 200°C, 220°C, 240°C, 260°C, 280°C, 300°C, etc., and the reaction pressure may include values ​​in any range of 0.5Mpa, 1Mpa, 2Mpa, 4Mpa, 6Mpa, etc. Preferably, the reaction temperature is 240-260°C, and the reaction pressure is 4-6Mpa.

[0065] In order to better understand the Co-based supported catalyst rich in oxygen vacancies, the preparation method and the application thereof in the preparation of mixed enols from synthesis gas in the present invention, the Co-based supported catalyst rich in oxygen vacancies, the preparation method and the application thereof in the preparation of mixed enols from synthesis gas in the present invention are described below with reference to specific examples. It should be noted that these examples are merely illustrative and do not limit the present invention in any way.

[0066] Example 1

[0067] This embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies, comprising the following steps:

[0068] S1. A commercial rutile phase r-TiO2 carrier purchased from Aladdin is provided as a reducing carrier, and the reducing carrier is pretreated (dried at 120°C for 24 hours to remove surface adsorbed water). The theoretical water absorption capacity of the reducing carrier is 1.0 g / (gH2O);

[0069] S2. Co(NO3)2·6H2O was prepared into 25 mL of a Co-based metal salt solution, 5 g of a reducing carrier was immersed in the 25 mL of the Co-based metal salt solution, the mass percentage of the Co element and the reducing carrier was controlled to be 30%, and then excess water was evaporated by a rotary evaporator at a temperature of 60°C and a pressure of -0.1 MPa to obtain a catalyst precursor solution;

[0070] S3, placing the catalyst precursor liquid in a muffle furnace, calcining at 350° C. for 4 h, and then grinding, tableting, and sieving to 40-60 mesh to obtain a Co-based supported catalyst precursor;

[0071] S4. The Co-based supported catalyst precursor is reduced at 400° C. for 5 h in a pure H2 atmosphere, and then carbonized for 10 h in a pure CO atmosphere at normal pressure to obtain a Co-based supported catalyst rich in oxygen vacancies.

[0072] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed enols from syngas. The reaction conditions are: raw gas molar ratio H2 / CO=2.0, reaction pressure 4.0 MPa, reaction temperature 260°C, raw gas space velocity 2000 mL g Cat.-1 h -1 The evaluation results of its catalytic performance are shown in Table 1.

[0073] Example 2

[0074] This embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies. The difference between the preparation method and that in Example 1 is that the reducing carrier used in step S1 is a commercial rutile phase a-TiO2 carrier purchased from Aladdin, and the other steps and methods are the same as those in Example 1 and will not be repeated here.

[0075] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed enols from syngas. The specific method is the same as that in Example 1 and will not be repeated here. The evaluation results of the catalytic performance are shown in Table 1.

[0076] Example 3

[0077] This embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies. The difference between the preparation method and that in Example 1 is that the reducing carrier used in step S1 is a commercial P25 TiO2 carrier purchased from Aladdin. The other steps and methods are the same as those in Example 1 and will not be repeated here.

[0078] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed enols from syngas. The specific method is the same as that in Example 1 and will not be repeated here. The evaluation results of the catalytic performance are shown in Table 1.

[0079] Example 4

[0080] This embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies. The preparation method is the same as that in Example 1 and will not be described in detail here.

[0081] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed enols from syngas. The specific method is different from that in Example 1 in that the reaction temperature is 240°C. The other methods are the same as those in Example 1 and will not be described in detail. The evaluation results of the catalytic performance are shown in Table 1.

[0082] Example 5

[0083] This embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies. The preparation method is the same as that in Example 1 and will not be described in detail here.

[0084] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed enols from syngas. The specific method is different from that in Example 1 in that the reaction pressure is 6.0 MPa and the reaction temperature is 240°C. The other methods are the same as those in Example 1 and will not be described in detail. The evaluation results of the catalytic performance are shown in Table 1.

[0085] Example 6

[0086] This embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies. The preparation method is the same as that in Example 1 and will not be described in detail here.

[0087] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed ene alcohol from synthesis gas. The specific method is different from that in Example 1 in that the molar ratio of the raw gas H2 / CO=1.0, and the other methods are the same as those in Example 1, which will not be repeated here. The evaluation results of the catalytic performance are shown in Table 1.

[0088] Example 7

[0089] This embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies. The preparation method is different from that in Example 1 in that the carbonization treatment in step S4 is carbonization at 0.5 MPa for 10 hours. Other methods and steps are the same as those in Example 1 and will not be repeated here.

[0090] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed enols from syngas. The specific method is the same as that in Example 1 and will not be repeated here. The evaluation results of the catalytic performance are shown in Table 1.

[0091] Example 8

[0092] This embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies. The preparation method is different from that in Example 1 in that the mass percentage of the Co element reducing carrier in step S2 is controlled to be 15%; the carbonization treatment in step S4 is carbonization at 0.5 MPa for 10 hours; other methods and steps are the same as those in Example 1 and will not be repeated here.

[0093] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed ene alcohol from synthesis gas. The specific method is different from that in Example 1 in that the reaction pressure is 6.0 MPa, and the other methods are the same as those in Example 1, which will not be described in detail. The evaluation results of the catalytic performance are shown in Table 1.

[0094] Example 9

[0095] The present embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies. The preparation method is different from that in Example 1 in that: in step S4, the Co-based supported catalyst is first reduced in a pure H2 atmosphere at 450°C for 5 hours, and then carbonized in a pure CO atmosphere at 0.5 MPa for 10 hours. Other methods and steps are the same as those in Example 1 and are not repeated here.

[0096] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed enols from syngas. The reaction conditions are: raw gas molar ratio H2 / CO=2.0, reaction pressure 6.0 MPa, reaction temperature 260°C, raw gas space velocity 1000 mL g Cat. -1 h -1 The evaluation results of its catalytic performance are shown in Table 1.

[0097] Example 10

[0098] This embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies. The preparation method is different from that in Example 1 in that the catalyst is calcined at 400° C. for 5 h in step S3. Other methods and steps are the same as those in Example 1 and will not be described in detail herein.

[0099] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed ene alcohol from synthesis gas. The specific method is different from that in Example 1 in that the reaction pressure is 6.0 MPa, and the other methods are the same as those in Example 1, which will not be described in detail. The evaluation results of the catalytic performance are shown in Table 1.

[0100] Embodiment 11

[0101] This embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies, comprising the following steps:

[0102] S1. Provide a commercial CeO2 carrier as a reducing carrier, and pretreat the reducing carrier (dry at 120°C for 24h to remove surface adsorbed water). The theoretical water absorption capacity of the reducing carrier is 0.8g / (gH2O);

[0103] S2. Co(NO3)2·6H2O was prepared into 40 mL of Co-based metal salt solution, 5 g of reducing carrier was immersed in 40 mL of Co-based metal salt solution, the mass percentage of Co element and reducing carrier was controlled to be 30%, and then excess water was evaporated by rotary evaporator at a temperature of 60°C and a pressure of -0.1 MPa to obtain a catalyst precursor solution;

[0104] S3, placing the catalyst precursor liquid in a muffle furnace, calcining at 350° C. for 4 h, and then grinding, tableting, and sieving to 40-60 mesh to obtain a Co-based supported catalyst precursor;

[0105] S4. The Co-based supported catalyst precursor is reduced at 400° C. for 5 h in a pure H2 atmosphere, and then carbonized for 10 h in a pure CO atmosphere at normal pressure to obtain a Co-based supported catalyst rich in oxygen vacancies.

[0106] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed enols from syngas. The specific method is the same as that in Example 1 and will not be repeated here. The evaluation results of the catalytic performance are shown in Table 1.

[0107] Example 12

[0108] This embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies, comprising the following steps:

[0109] S1. Provide a commercial ZrO2 carrier as a reducing carrier, and pretreat the reducing carrier (dry at 120°C for 24 hours to remove surface adsorbed water). The theoretical water absorption capacity of the reducing carrier is 1.1 g / (gH2O);

[0110] S2. Co(NO3)2·6H2O was prepared into 55 mL of a Co-based metal salt solution, 5 g of a reducing carrier was immersed in the 55 mL of the Co-based metal salt solution, the mass percentage of the Co element and the reducing carrier was controlled to be 20%, and then excess water was evaporated by a rotary evaporator at a temperature of 60°C and a pressure of -0.1 MPa to obtain a catalyst precursor solution;

[0111] S3, placing the catalyst precursor liquid in a muffle furnace, calcining at 350° C. for 4 h, and then grinding, tableting, and sieving to 40-60 mesh to obtain a Co-based supported catalyst precursor;

[0112] S4. The Co-based supported catalyst precursor is reduced at 400° C. for 5 h in a pure H2 atmosphere, and then carbonized for 10 h in a pure CO atmosphere at normal pressure to obtain a Co-based supported catalyst rich in oxygen vacancies.

[0113] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed enols from syngas. The specific method is different from that in Example 1 in that the reaction temperature is 250°C. The other methods are the same as those in Example 1 and will not be described in detail. The evaluation results of the catalytic performance are shown in Table 1.

[0114] Example 13

[0115] This embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies, comprising the following steps:

[0116] S1. Provide a commercial MoO3 carrier as a reducing carrier, and pretreat the reducing carrier (dry at 120°C for 24h to remove surface adsorbed water), the theoretical water absorption capacity of the reducing carrier is 0.6g / (gH2O);

[0117] S2. Co(NO3)2·6H2O was prepared into 30 mL of Co-based metal salt solution, 5 g of reducing carrier was immersed in 30 mL of Co-based metal salt solution, the mass percentage of Co element and reducing carrier was controlled to be 30%, and then excess water was evaporated by rotary evaporator at 60°C and -0.1 MPa to obtain catalyst precursor solution;

[0118] S3, placing the catalyst precursor liquid in a muffle furnace, calcining at 350° C. for 4 h, and then grinding, tableting, and sieving to 40-60 mesh to obtain a Co-based supported catalyst precursor;

[0119] S4. The Co-based supported catalyst precursor is reduced at 400° C. for 5 h in a pure H2 atmosphere, and then carbonized for 10 h in a pure CO atmosphere at normal pressure to obtain a Co-based supported catalyst rich in oxygen vacancies.

[0120] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed enols from syngas. The specific method is different from that in Example 1 in that the raw gas space velocity is 1000 mL g Cat. -1 h -1 The other aspects are the same as those in Example 1 and will not be described in detail herein. The evaluation results of the catalytic performance are shown in Table 1.

[0121] Embodiment 14

[0122] This embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies, comprising the following steps:

[0123] S1. Provide a commercial WO3 carrier as a reducing carrier, and pretreat the reducing carrier (dry at 120°C for 24 hours to remove surface adsorbed water). The theoretical water absorption capacity of the reducing carrier is 0.9 g / (gH2O);

[0124] S2. Co(NO3)2·6H2O was prepared into 45 mL of Co-based metal salt solution, 5 g of reducing carrier was immersed in 45 mL of Co-based metal salt solution, the mass percentage of Co element and reducing carrier was controlled to be 20%, and then excess water was evaporated by rotary evaporator at 60°C and -0.1 MPa to obtain catalyst precursor solution;

[0125] S3, placing the catalyst precursor liquid in a muffle furnace, calcining at 350° C. for 4 h, and then grinding, tableting, and sieving to 40-60 mesh to obtain a Co-based supported catalyst precursor;

[0126] S4. The Co-based supported catalyst precursor is reduced at 400° C. for 5 h in a pure H2 atmosphere, and then carbonized for 10 h in a pure CO atmosphere at normal pressure to obtain a Co-based supported catalyst rich in oxygen vacancies.

[0127] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed enols from syngas. The specific method is different from that in Example 1 in that the reaction pressure is 6.0 MPa, the feed gas space velocity is 1000 mL g Cat. -1 h -1 The other aspects are the same as those in Example 1 and will not be described in detail herein. The evaluation results of the catalytic performance are shown in Table 1.

[0128] Embodiment 15

[0129] This embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies, comprising the following steps:

[0130] S1. Provide a commercial V2O3 carrier as a reducing carrier, and pretreat the reducing carrier (dry at 120°C for 24 hours to remove surface adsorbed water). The theoretical water absorption capacity of the reducing carrier is 0.9 g / (gH2O);

[0131] S2. Co(NO3)2·6H2O was prepared into 45 mL of Co-based metal salt solution, 5 g of reducing carrier was immersed in 45 mL of Co-based metal salt solution, the mass percentage of Co element and reducing carrier was controlled to be 30%, and then excess water was evaporated by rotary evaporator at a temperature of 60°C and a pressure of -0.1 MPa to obtain a catalyst precursor solution;

[0132] S3, placing the catalyst precursor liquid in a muffle furnace, calcining at 350° C. for 4 h, and then grinding, tableting, and sieving to 40-60 mesh to obtain a Co-based supported catalyst precursor;

[0133] S4. The Co-based supported catalyst precursor is reduced at 400° C. for 5 h in a pure H2 atmosphere, and then carbonized for 10 h in a pure CO atmosphere at normal pressure to obtain a Co-based supported catalyst rich in oxygen vacancies.

[0134] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed enols from syngas. The specific method is different from that in Example 1 in that the reaction pressure is 5.0 MPa, the feed gas space velocity is 1000 mL g Cat. -1 h -1 The other aspects are the same as those in Example 1 and will not be described in detail herein. The evaluation results of the catalytic performance are shown in Table 1.

[0135] Example 16

[0136] This embodiment provides a method for preparing a Co-based supported catalyst rich in oxygen vacancies, comprising the following steps:

[0137] S1. Provide a commercial MnO2 carrier as a reducing carrier, and pretreat the reducing carrier (dry at 120°C for 24 hours to remove surface adsorbed water). The theoretical water absorption capacity of the reducing carrier is 1.1 g / (gH2O);

[0138] S2. Co(NO3)2·6H2O was prepared into 55 mL of a Co-based metal salt solution, 5 g of a reducing carrier was immersed in the 55 mL of the Co-based metal salt solution, the mass percentage of the Co element and the reducing carrier was controlled to be 30%, and then excess water was evaporated by a rotary evaporator at a temperature of 60°C and a pressure of -0.1 MPa to obtain a catalyst precursor solution;

[0139] S3, placing the catalyst precursor liquid in a muffle furnace, calcining at 350° C. for 4 h, and then grinding, tableting, and sieving to 40-60 mesh to obtain a Co-based supported catalyst precursor;

[0140] S4. The Co-based supported catalyst precursor is reduced at 400° C. for 5 h in a pure H2 atmosphere, and then carbonized for 10 h in a pure CO atmosphere at normal pressure to obtain a Co-based supported catalyst rich in oxygen vacancies.

[0141] This embodiment also provides an application of a Co-based supported catalyst rich in oxygen vacancies. The Co-based supported catalyst prepared in this embodiment is applied to the reaction of synthesizing mixed ene alcohol from synthesis gas. The specific method is different from that in Example 1 in that the reaction pressure is 6.0 MPa, and the other methods are the same as those in Example 1, which will not be described in detail. The evaluation results of the catalytic performance are shown in Table 1.

[0142] Comparative Example 1

[0143] The present comparative example provides a Co-based catalyst, and the preparation method of the Co-based catalyst is as follows: Co(NO3)2·6H2O is placed in a muffle furnace, calcined at 350°C for 4h, and then ground, tableted, and sieved to 40-60 mesh to obtain a Co-based catalyst precursor; then reduced in a pure H2 atmosphere at 400°C for 5h, and then carbonized in a pure CO atmosphere at normal pressure for 10h to obtain a Co-based catalyst.

[0144] This comparative example also provides an application of a Co-based catalyst in the reaction of synthesizing mixed enols from synthesis gas. The reaction conditions are: raw gas molar ratio H2 / CO = 2.0, reaction pressure 4.0 MPa, reaction temperature 260°C, raw gas space velocity 2000 mL g Cat. - 1 h -1 The evaluation results of its catalytic performance are shown in Table 1.

[0145] Table 1. Catalytic performance evaluation results of the Co-based supported catalysts rich in oxygen vacancies prepared in Examples 1 to 15 in the reaction of synthesizing mixed enolates from syngas

[0146]

[0147] According to the experimental results of the above-mentioned Examples 1 to 16, and in combination with the data of Comparative Example 1, it can be seen that the oxygen vacancy-rich Co-based supported catalyst of the present invention has relatively excellent performance in preparing mixed alcohol-olefins from synthesis gas, which is mainly attributed to the introduction of oxygen vacancies, which not only directly increases the active sites of the catalyst, but also regulates the physical phase composition of the Co element, making it more conducive to the formation of alcohol-olefin products.

[0148] In summary, the present invention impregnates the reducing carrier in a Co-based metal salt solution by an excessive impregnation method, and obtains a Co-based supported catalyst rich in oxygen vacancies by roasting. The preparation method is simple, the synthesis equipment is simple, the raw material cost is low, and it is easy to industrially scale up and apply. The mass proportion of the Co element in the prepared oxygen-rich Co-based supported catalyst is precisely controllable, and the reducing carrier is partially reduced to produce oxygen vacancy active sites, which not only directly increases the active sites of the catalyst, but also regulates the physical phase composition of the Co element, further promotes the catalytic performance of the Co component, and strengthens the catalytic performance of the synthesis gas to mixed enol reaction, thereby achieving higher catalytic activity and target product selectivity. Therefore, the present invention effectively overcomes the various shortcomings in the prior art and has a high industrial utilization value.

[0149] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A method for preparing a Co-based supported catalyst rich in oxygen vacancies, characterized in that: The preparation method comprises the following steps: S1, providing a reducing carrier, and pretreating the reducing carrier; S2, preparing a Co-based metal salt solution, and impregnating the reducing carrier into the Co-based metal salt solution by an excess impregnation method to obtain a catalyst precursor solution; S3, drying the catalyst precursor liquid, then calcining it, and then grinding, tableting, and sieving it to obtain a Co-based supported catalyst precursor; S4, subjecting the Co-based supported catalyst precursor to reduction treatment and carbonization treatment to obtain a Co-supported catalyst rich in oxygen vacancies.

2. The method for preparing the oxygen vacancy-rich Co-based supported catalyst according to claim 1, characterized in that: Step S1 includes one or a combination of the following conditions: The reducing carrier includes one or a combination of TiO2, CeO2, ZrO2, MoO3, WO3, V2O3, and MnO2; The pretreatment specifically comprises drying the reducing carrier, wherein the drying is performed at 50 to 120° C. for 12 to 24 hours.

3. The method for preparing the oxygen vacancy-rich Co-based supported catalyst according to claim 1, characterized in that: The Co source in the Co-based metal salt solution in step S2 includes one or a combination of cobalt nitrate, cobalt chloride, cobalt oxalate, cobalt acetate, and cobalt sulfate.

4. The method for preparing the oxygen vacancy-rich Co-based supported catalyst according to claim 1, characterized in that: Step S2 includes one or a combination of the following conditions: The mass percentage between the Co element in the Co-based metal salt solution and the reducing carrier is 5% to 50%; The volume of the Co-based metal salt solution is 2 to 10 times the theoretical water absorption capacity of the reducing carrier.

5. The method for preparing the oxygen vacancy-rich Co-based supported catalyst according to claim 1, characterized in that: Step S3 includes one or a combination of the following conditions: Before drying the catalyst precursor liquid after impregnation, a rotary evaporation step is also included, wherein the rotary evaporation is specifically to use a rotary evaporator to rotary evaporate the catalyst precursor liquid after impregnation under a vacuum state to obtain a solid precursor; The drying temperature is 50-120°C, and the drying time is 12-24h; The calcination temperature is 300-600° C., and the calcination time is 4-10 hours.

6. The method for preparing the oxygen vacancy-rich Co-based supported catalyst according to claim 1, characterized in that: Step S4 includes one or a combination of the following conditions: The reducing atmosphere of the reduction treatment is pure H2 or H2 / Ar mixed gas, the reducing temperature is 300-500°C, and the reducing time is 5-10h; The carbonization atmosphere of the carbonization treatment is pure CO or synthesis gas with a H2 / CO molar ratio of 0.5 to 2.0, the carbonization pressure is 0.1 to 1 MPa, and the carbonization time is 5 to 24 hours.

7. The method for preparing the oxygen vacancy-rich Co-based supported catalyst according to claim 1, characterized in that: The particle size of the Co-based supported catalyst obtained in step S4 is 20 to 80 meshes.

8. A Co-based supported catalyst rich in oxygen vacancies, characterized in that: The Co-based supported catalyst is prepared by the method for preparing the oxygen vacancy-rich Co-based supported catalyst according to any one of claims 1 to 7.

9. Application of a Co-based supported catalyst rich in oxygen vacancies in the reaction of synthesizing mixed enols from synthesis gas, characterized in that: The Co-based supported catalyst is prepared by the preparation method described in any one of claims 1 to 7.

10. Use of the oxygen vacancy-rich Co-based supported catalyst according to claim 9 in the reaction of synthesizing mixed enols from synthesis gas, characterized in that: The reaction conditions for the synthesis gas to mixed enol reaction include one or a combination of the following conditions: The molar ratio of H2 to CO in the feed gas is 0.5-2.0, and the space velocity of the feed gas is 500-10000 mL g Cat. -1 h -1 ; The reaction temperature is 200-300°C, and the reaction pressure is 0.5-6.0Mpa.

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