A coce composite oxide catalyst, a preparation method thereof, and a method for catalyzing dehydrogenation of propane to propylene

Abstract

The application belongs to the technical field of supported catalysts, and discloses a CoCe composite oxide catalyst, a preparation method thereof and a method for catalyzing propane dehydrogenation to prepare propylene; the catalyst is a CoCe composite oxide supported by a gamma-Al2O3 carrier, wherein the mass ratio of Ce to the gamma-Al2O3 is 10% to 40%, and the mass ratio of Co to the CeO2 / gamma-Al2O3 is 0.5% to 2%; the preparation method is as follows: a step-by-step impregnation method is used to impregnate cerium nitrate on the gamma-Al2O3 carrier first, the precursor is dried, pyrolysis is carried out in air, and a gamma-Al2O3 supported Ce oxide catalyst is obtained; then, cobalt nitrate is impregnated on the CeO2 / gamma-Al2O3, and after drying and pyrolysis in air, a CoO-CeO2 / gamma-Al2O3 catalyst is obtained. The application utilizes the oxide carrier interaction between CoO and CeO2 to improve the reaction performance; the application takes the non-noble metal oxide as an active center, the preparation method is simple, the price is low, and the toxicity is low; and the catalyst is used for catalyzing propane dehydrogenation to prepare propylene, and the performance is excellent.

Description

Technical Field

[0001] This invention belongs to the field of supported catalyst technology, specifically, it relates to a CoCe composite oxide catalyst and its preparation method, as well as a method for catalyzing the dehydrogenation of propane to propylene. Background Technology

[0002] Propylene, as an important basic raw material in the petrochemical industry, is used industrially in the preparation of various high-value-added products, including polypropylene, propylene oxide, isopropanol, ethyl acrylate, and acrylonitrile. Propylene derivatives also have wide applications in industrial production and daily life. For example, polypropylene, compared to polyethylene, has better mechanical properties and heat resistance, and is therefore widely used in food packaging and optical fibers. Propylene oxide can be used to produce polyether polyols and further synthesized into polyurethane foam materials, which are essential basic materials for thermal insulation, sound insulation, and waterproofing. Acrylonitrile can be polymerized with butadiene to form nitrile rubber, which has excellent elasticity, weather resistance, and chemical resistance, and is widely used in the automotive industry and other fields.

[0003] Compared to traditional fluidized bed catalytic cracking and naphtha steam cracking, which are hampered by fossil fuel consumption and suffer from low propylene selectivity in methanol-to-olefins (MTO), propane dehydrogenation to propylene is particularly important due to the shift of the refining industry towards chemical feedstock production, the abundance of feedstocks from shale gas development, and the targeted production of propylene. The propane dehydrogenation process selectively breaks the CH bonds in propane molecules under the action of a catalyst to generate the single product propylene, thus achieving a relatively high propylene yield. Furthermore, advancements in technologies such as hydraulic fracturing have enabled the efficient development of shale gas resources. The abundant propane components in shale gas significantly reduce the feedstock costs required for propane dehydrogenation, widening the market price gap between propane and propylene and greatly improving the economic viability of producing the higher value-added product propylene from propane dehydrogenation. Therefore, propane dehydrogenation to propylene technology is considered the most promising propylene production technology and has attracted widespread attention in both industrial applications and basic research.

[0004] Propane dehydrogenation plants, primarily using the Oleflex and Catofin processes, are widely deployed globally, but the Pt-based and CrO-based materials they utilize... x Traditional catalysts suffer from either high cost or high toxicity, making the search for inexpensive, low-toxicity, and high-performance alternative catalysts an urgent need. Summary of the Invention

[0005] The purpose of this invention is to solve the technical problems of high cost or high toxicity of existing propane dehydrogenation to propylene catalysts, and to provide a low-cost, low-toxicity, and high-performance CoO-CeO2 / γ-Al2O3 catalyst and its preparation method, as well as a method for catalyzing propane dehydrogenation to propylene using this catalyst.

[0006] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0007] According to one aspect of the present invention, a CoCe composite oxide catalyst is provided, wherein γ-Al2O3 is used as a support, and the γ-Al2O3 support supports CoCe composite oxide, expressed as CoO-CeO2 / γ-Al2O3; wherein the mass ratio of Ce to γ-Al2O3 is 10% to 40%, and the mass ratio of Co to CeO2 / γ-Al2O3 is 0.5% to 2%.

[0008] Preferably, the mass ratio of Ce to γ-Al2O3 is 10% to 20%.

[0009] Preferably, the mass ratio of Co to CeO2 / γ-Al2O3 is 0.5% to 1%.

[0010] According to another aspect of the present invention, a method for preparing the above-mentioned CoCe composite oxide catalyst is provided, comprising the following steps:

[0011] (1) Ce precursor solution A was prepared using Ce(NO3)3·6H2O. Precursor solution A was added dropwise to γ-Al2O3 powder. After shaking and sonication, a slurry-like mixture was obtained. The slurry-like mixture was dried, ground into powder, and calcined at 400℃~700℃ for 1~6h. The obtained product was denoted as CeO2 / γ-Al2O3.

[0012] When solution A is added dropwise to γ-Al2O3, the ratio of the volume of solution A in mL to the mass of the carrier γ-Al2O3 in g is controlled to be 1:1 to 4:1.

[0013] (2) A precursor solution B of Co was prepared using Co(NO3)2·6H2O. The precursor solution B was added dropwise to the CeO2 / γ-Al2O3 powder obtained in step (1). After shaking and sonication, a slurry-like mixture was obtained. The slurry-like mixture was dried, ground into powder, and calcined at 400-700℃ for 1-6 h. The resulting catalyst was denoted as CoO-CeO2 / γ-Al2O3.

[0014] When adding solution B dropwise to CeO2 / γ-Al2O3, the ratio of the volume of solution B in mL to the mass of CeO2 / γ-Al2O3 in g is controlled to be 1:1 to 4:1.

[0015] Furthermore, in steps (1) and (2), the drying is carried out in flowing air at 50℃~110℃ for 6~18h.

[0016] Preferably, in steps (1) and (2), the roasting temperature is 500℃~600℃ and the time is 2~4h.

[0017] Preferably, in step (1), when solution A is added dropwise to γ-Al2O3, the ratio of the volume of solution A in mL to the mass of carrier γ-Al2O3 in g is controlled to be 2:1 to 3:1.

[0018] Preferably, in step (2), when adding solution B dropwise to CeO2 / γ-Al2O3, the ratio of the volume of solution B in mL to the mass of CeO2 / γ-Al2O3 in g is controlled to be 1.2:1 to 2:1.

[0019] According to another aspect of the present invention, a method for catalytic dehydrogenation of propane to propylene is provided, wherein the above-mentioned CoO-CeO2 / γ-Al2O3 catalyst is placed in a fixed-bed reactor and subjected to a total pressure of 0.1–0.14 MPa, a propane atmosphere of 10–50 kPa, a temperature of 550–620 °C, for 0.5–4 h. -1 Propylene was obtained under weight-space velocity conditions.

[0020] Furthermore, under a total pressure of 0.1–0.12 MPa, a propane atmosphere of 15–30 kPa, and a temperature of 570–590 °C, for 1–2 hours... -1 Reactions under weight-space velocity conditions.

[0021] The beneficial effects of this invention are:

[0022] The CoCe composite oxide catalyst of this invention utilizes the oxide support interaction between CoO and CeO2 to improve the Co production during the preparation process. 2+ And further inhibited Co 2+ The deep reduction of active sites in propane dehydrogenation improves reaction performance; it uses non-precious metal oxides as active centers, has a simple preparation method, low price, and low toxicity; this catalyst is used to catalyze the dehydrogenation of propane to propylene, with excellent performance, propane conversion rate of 31.3-51.8%, and propylene selectivity of 67.2-87.5%. Attached Figure Description

[0023] Figure 1 The graph shows the conversion results of xCoO-yCeO2 / γ-Al2O3 with different loading amounts;

[0024] Figure 2 This is a graph showing the selectivity results for different loading amounts of xCoO-yCeO2 / γ-Al2O3;

[0025] Figure 3 The graph shows the conversion and selectivity results of 1CoO-yCeO2 / γ-Al2O3 with different Ce loadings;

[0026] Figure 4 The graph shows the conversion and selectivity results of the 1CoO-20CeO2 / γ-Al2O3 reaction at different temperatures;

[0027] Figure 5 The graph shows the conversion and selectivity results of the reaction of 1CoO-20CeO2 / γ-Al2O3 at different weight space-time velocities;

[0028] Figure 6 The figure shows the stability test results of 1CoO-20CeO2 / γ-Al2O3 catalytic propane dehydrogenation to propylene recycling 20 times in a fixed-bed reactor;

[0029] Figure 7 These are in-situ diffuse reflectance infrared images of 20CeO2 / γ-Al2O3 reduced at different temperatures using 18 vol.% H2 / Ar;

[0030] Figure 8 The images show the in-situ diffuse reflectance infrared spectra of 1CoO-20CeO2 / γ-Al2O3 reduced at different temperatures in 18 vol.% H2 / Ar.

[0031] Figure 9 These are in-situ XPS images of Co 2p for xCoO-yCeO2 / γ-Al2O3 with different loadings;

[0032] Figure 10 This is a quasi-in-situ XPS image of Co 2p before and after the reaction of 1CoO-20CeO2 / γ-Al2O3 in propane at 20 kPa for 20 min. Detailed Implementation

[0033] This invention provides a CoCe composite oxide catalyst, using γ-Al2O3 as a support, with CoCe composite oxide supported on the γ-Al2O3 support, expressed as CoO-CeO2 / γ-Al2O3; wherein the mass ratio of Ce to γ-Al2O3 is 10% to 40%, and the mass ratio of Co to CeO2 / γ-Al2O3 is 0.5% to 2%.

[0034] In some preferred embodiments of the present invention, the mass ratio of Ce to γ-Al2O3 is 10% to 20%.

[0035] In some preferred embodiments of the present invention, the mass ratio of Co to CeO2 / γ-Al2O3 is 0.5% to 1%.

[0036] This invention also provides a method for preparing the above-mentioned CoCe composite oxide catalyst, comprising the following steps:

[0037] A certain amount of Ce(NO3)3·6H2O was weighed out as a precursor of Ce and dissolved in a certain amount of ultrapure water to form precursor solution A. A certain amount of γ-Al2O3 powder was weighed out as a carrier, and solution A was added dropwise to the γ-Al2O3 powder. After shaking and sonication, a slurry-like mixture was obtained. The obtained slurry-like mixture was transferred to an oven and dried in flowing air at 50℃~110℃ for 6~18h. Then, the dried mixture was ground into powder and placed in a muffle furnace and calcined at 400℃~700℃ for 1~6h. The obtained catalyst is denoted as yCeO2 / γ-Al2O3, where y represents the mass ratio of Ce to γ-Al2O3.

[0038] A certain amount of Co(NO3)2·6H2O was weighed out as a precursor of Co and dissolved in a certain amount of ultrapure water to form precursor solution B. A certain amount of yCeO2 / γ-Al2O3 powder was weighed out, and solution B was added dropwise to the yCeO2 / γ-Al2O3 powder. After shaking and sonication, a slurry-like mixture was obtained. The obtained slurry-like mixture was transferred to an oven and dried in flowing air at 50℃~110℃ for 6~18h. Then, the dried mixture was ground into powder and placed in a muffle furnace and calcined at 400℃~700℃ for 1~6h. The obtained catalyst was denoted as xCoO-yCeO2 / γ-Al2O3, where x represents the mass ratio of Co to yCeO2 / γ-Al2O3.

[0039] When solution A is added dropwise to the carrier γ-Al2O3, the ratio of the volume of solution A in mL to the mass of carrier γ-Al2O3 in g is controlled to be 1:1 to 4:1; when solution B is added dropwise to yCeO2 / γ-Al2O3, the ratio of the volume of solution B in mL to the mass of yCeO2 / γ-Al2O3 in g is controlled to be 1:1 to 4:1.

[0040] In some preferred embodiments of the present invention, when solution A is added dropwise to carrier γ-Al2O3, the numerical ratio of the volume of solution A in mL to the mass of carrier γ-Al2O3 in g is controlled to be 2:1 to 3:1.

[0041] In some preferred embodiments of the present invention, when solution B is added dropwise to yCeO2 / γ-Al2O3, the numerical ratio of the volume of solution B in mL to the mass of yCeO2 / γ-Al2O3 in g is controlled to be 1.2:1 to 2:1.

[0042] In some preferred embodiments of the present invention, both loading processes involve drying the resulting slurry mixture in flowing air at 80°C to 90°C for 8 to 12 hours, followed by calcining the dried mixture at 500°C to 600°C for 2 to 4 hours.

[0043] The present invention also provides a method for the catalytic dehydrogenation of propane to propylene using the above-mentioned CoCe composite oxide catalyst, wherein the CoO-CeO2 / γ-Al2O3 catalyst is placed in a fixed-bed reactor and subjected to a total pressure of 0.1–0.14 MPa, a propane atmosphere of 10–50 kPa, a temperature of 550–620 °C, and a reaction time of 0.5–4 h. -1 Propylene was obtained under weight-space velocity conditions.

[0044] In some preferred embodiments of the present invention, the process is carried out at a total pressure of 0.1–0.12 MPa, a propane atmosphere of 15–30 kPa, and a temperature of 570–590°C for 1–2 hours. -1 Reactions under weight-space velocity conditions.

[0045] The present invention will be further described in detail below through specific embodiments. These embodiments will enable those skilled in the art to have a more comprehensive understanding of the present invention, but will not limit the present invention in any way.

[0046] Example 1

[0047] The catalyst is prepared with a Ce to γ-Al2O3 mass ratio of 0% and a Co to CeO2 / γ-Al2O3 mass ratio of 1%.

[0048] 0.050 g of Co(NO3)2·6H2O was dissolved in 2 mL of ultrapure water to obtain solution B; 1 g of γ-Al2O3 was weighed; solution B was added dropwise to γ-Al2O3, and after shaking and sonication, a slurry-like mixture was obtained; the obtained slurry-like mixture was transferred to an oven and dried in flowing air at 80 °C for 12 h; then the dried mixture was ground into powder and placed in a muffle furnace and calcined at 600 °C for 2 h to obtain the composite metal oxide catalyst 1Co / Al.

[0049] Example 2

[0050] The catalyst contains 20% Ce to γ-Al2O3 by mass and 0.5% Co to 20CeO2 / γ-Al2O3 by mass.

[0051] 0.620 g of Ce(NO3)3·6H2O was weighed and dissolved in 2 mL of ultrapure water to obtain solution A; 1 g of γ-Al2O3 was weighed; solution A was added dropwise to γ-Al2O3, and after shaking and sonication, a slurry-like mixture was obtained; the slurry-like mixture was transferred to an oven and dried in flowing air at 80 °C for 12 h; then the dried mixture was ground into powder and placed in a muffle furnace and calcined at 600 °C for 2 h to obtain 20CeAl.

[0052] 0.025 g of Co(NO3)2·6H2O was dissolved in 1.3 mL of ultrapure water to obtain solution B; 1 g of 20CeAl was weighed; solution B was added dropwise to 20CeAl, and after shaking and sonication, a slurry-like mixture was obtained; the obtained slurry-like mixture was transferred to an oven and dried in flowing air at 80 °C for 12 h; then the dried mixture was ground into powder and placed in a muffle furnace and calcined at 600 °C for 4 h to obtain 0.5Co / 20CeAl.

[0053] Example 3

[0054] The preparation was carried out according to the steps of Example 2, except that the mass ratio of Co to 20CeO2 / γ-Al2O3 was 1%. 0.050 g of Co(NO3)2·6H2O was weighed and dissolved in 1.3 mL of ultrapure water to obtain solution B; finally, 1Co / 20CeAl was obtained.

[0055] Example 4

[0056] The preparation was carried out according to the steps of Example 2, except that the mass ratio of Co to 20CeO2 / γ-Al2O3 was 2%. 0.100 g of Co(NO3)2·6H2O was weighed and dissolved in 1.3 mL of ultrapure water to obtain solution B; finally, 2Co / 20CeAl was obtained.

[0057] Example 5

[0058] The catalyst contains 20% Ce to γ-Al2O3 by mass and 0% Co to 20CeO2 / γ-Al2O3 by mass.

[0059] 0.620 g of Ce(NO3)3·6H2O was weighed and dissolved in 2 mL of ultrapure water to obtain solution A; 1 g of γ-Al2O3 was weighed; solution A was added dropwise to γ-Al2O3, and after shaking and sonication, a slurry-like mixture was obtained; the slurry-like mixture was transferred to an oven and dried in flowing air at 80 °C for 12 h; then the dried mixture was ground into powder and placed in a muffle furnace and calcined at 600 °C for 2 h to obtain 20CeAl.

[0060] Example 6

[0061] The preparation was carried out according to the steps of Example 2, except that the mass ratio of Ce to γ-Al2O3 was 10% and the mass ratio of Co to 10CeO2 / γ-Al2O3 was 1%. 0.310 g of Ce(NO3)3·6H2O was weighed and dissolved in 2 mL of ultrapure water to obtain solution A; 0.050 g of Co(NO3)2·6H2O was weighed and dissolved in 1.3 mL of ultrapure water to obtain solution B; finally, 1Co / 10CeAl was obtained.

[0062] Example 7

[0063] The preparation was carried out according to the steps of Example 2, except that the mass ratio of Ce to γ-Al2O3 was 40% and the mass ratio of Co to 40CeO2 / γ-Al2O3 was 1%. 1.240 g of Ce(NO3)3·6H2O was weighed and dissolved in 2 mL of ultrapure water to obtain solution A; 0.050 g of Co(NO3)2·6H2O was weighed and dissolved in 1.3 mL of ultrapure water to obtain solution B; finally, 1Co / 40CeAl was obtained.

[0064] The catalysts prepared in Examples 1-5 are used to catalyze the dehydrogenation of propane to propylene, and the specific methods are as follows:

[0065] 0.5 g of catalyst was placed in a fixed-bed reactor and subjected to an incubation period of 1 h at a total pressure of 0.1 MPa, a propane atmosphere of 19 kPa, and 590 °C. -1 The reaction was carried out at a weight-space-time velocity, and the products were detected by GC. The reaction results for each embodiment are shown below. Figure 1 and Figure 2 .

[0066] Depend on Figure 1 and Figure 2 It can be seen that the catalysts prepared in Examples 1 to 5 have excellent performance in catalyzing the dehydrogenation of propane to propylene. Among them, 1Co / 20CeAl has the best performance, achieving the best performance of 46.9% propane conversion and 86.6% propylene selectivity in 5 min.

[0067] The inventors used the catalysts prepared in Examples 6 and 7 to catalyze the dehydrogenation of propane to propylene. 0.5 g of the catalyst was placed in a fixed-bed reactor, and the reactor was subjected to a total pressure of 0.1 MPa, a propane atmosphere of 19 kPa, and a temperature of 590°C for 1 hour. -1 The reaction was carried out at a weight-space velocity, and the products were detected by GC. The reaction results are shown below. Figure 3 .

[0068] Depend on Figure 3 It can be seen that as the Ce content increases from 10% to 40%, the conversion rate gradually increases to 49.8% of 1Co / 40CeAl, but the selectivity of 1Co / 40CeAl decreases to 68.2%, so the optimal performance is achieved in 1Co / 20CeAl.

[0069] The inventors placed 0.5 g of the composite oxide catalyst from Example 3 into a fixed-bed reactor and incubated it at a total pressure of 0.1 MPa, a propane atmosphere of 19 kPa, and a temperature of 550–590 °C for 1 hour. -1 The reaction was carried out at a weight-space velocity, and the products were detected by GC. The reaction results are shown below. Figure 4 .

[0070] Depend on Figure 4It can be seen that as the reaction temperature gradually increases from 550℃ to 590℃, the reaction performance of 1Co / 20CeAl gradually improves, and the optimal reaction performance is achieved at 590℃.

[0071] The inventors placed 0.5 g of the composite oxide catalyst from Example 3 into a fixed-bed reactor and incubated it at a total pressure of 0.1 MPa, a propane atmosphere of 19 kPa, and a temperature of 590 °C for 1–4 hours. -1 The reaction was carried out at a weight-space velocity, and the products were detected by GC. The reaction results are shown below. Figure 5 .

[0072] Depend on Figure 5 It can be seen that as the spacetime velocity of weight increases from 4h... -1 up to 1 hour -1 The reaction performance of 1Co / 20CeAl gradually increases as the temperature decreases, reaching a peak within 1 hour. -1 To achieve optimal reaction performance.

[0073] The inventors used the composite oxide catalyst from Example 3 to catalyze the dehydrogenation of propane to propylene, and then regenerated it at 590°C with 10 vol.% O2 / N2 for 15 min, recycling it. The recycling effect is shown in [see figure]. Figure 6 .

[0074] Depend on Figure 6 It is evident that the catalyst of this invention is recyclable and exhibits good cycle stability.

[0075] The in-situ diffuse reflectance infrared spectroscopy of the catalysts prepared in Examples 3 and 5 above, reduced at different temperatures of 18 vol.% H2 / Ar, was measured. The results are shown in the figure. Figure 7 and Figure 8 .Depend on Figure 7 and Figure 8 It can be seen that the initial generation temperature of oxygen vacancies in CeO2 on the surface of 20CeAl is 450℃, while the initial generation temperature of oxygen vacancies in CeO2 on the surface of 1Co / 20CeAl is 400℃. This indicates that there is oxygen supply from CeO2 to CoO, which leads to the formation of oxygen vacancies in CeO2 at a lower temperature. This helps to maintain the partial oxidation state of CoO, and there is an oxide carrier interaction between CoO and CeO2.

[0076] The catalysts prepared in Examples 1-4 above were characterized by in-situ XPS, and the results are shown in the figure. Figure 9 .Depend on Figure 9 Calculated Co 2+ The content is shown in Table 1.

[0077] Table 1. Co content in different catalysts 2+ content

[0078]

[0079] As shown in Table 1, compared to 1Co / Al, 1Co / 20CeAl has a lower Co content. 2+ The content was increased due to the interaction between the oxide carriers of CoO and CeO2, which improved the Co content generated during the preparation process. 2+ content.

[0080] The quasi-in-situ XPS values ​​of the catalyst prepared in Example 3 above were measured before and after reduction at 20 vol.% C3H8 / N2 for 20 min. The results are shown in [Figure number missing]. Figure 10 .Depend on Figure 10 It is evident that no Co was produced after reduction. 0 The oxide support interaction between CoO and CeO2 inhibits Co 2+ Propane dehydrogenation active sites are deeply reduced.

[0081] In summary, the CoCe composite oxide catalyst prepared by this invention uses non-noble metal oxides as active centers and, through the interaction between CoO and CeO2 oxide supports, improves the Co content generated during the preparation process. 2+ And further inhibited Co 2+ Propane dehydrogenation active sites are deeply reduced, improving reaction performance. Propane conversion is 31.3-51.8%, and propylene selectivity is 67.2-87.5%. Within the preferred range, propane conversion is 31.3-46.9%, and propylene selectivity is 83.4-87.5%.

[0082] Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many specific modifications under the guidance of the present invention without departing from the spirit and scope of the claims, and these modifications all fall within the scope of protection of the present invention.

Claims

1. A method for the dehydrogenation of propane to propylene catalyzed by a CoCe composite oxide catalyst, characterized in that, The CoCe composite oxide catalyst uses γ-Al2O3 as a support, with CoCe composite oxide supported on the γ-Al2O3 support, expressed as CoO-CeO2 / γ-Al2O3; wherein the mass ratio of Ce to γ-Al2O3 is 10%–40%, and the mass ratio of Co to CeO2 / γ-Al2O3 is 0.5%–2%; The CoO-CeO2 / γ-Al2O3 catalyst was placed in a fixed-bed reactor and subjected to a total pressure of 0.1–0.14 MPa, a propane atmosphere of 10–50 kPa, and a temperature of 550–620 °C for 0.5–4 h. -1 Propylene was obtained under weight-space velocity conditions.

2. The method for catalyzing propane dehydrogenation to propylene using a CoCe composite oxide catalyst according to claim 1, characterized in that, The mass ratio of Ce to γ-Al2O3 is 10% to 20%.

3. The method for catalyzing propane dehydrogenation to propylene using a CoCe composite oxide catalyst according to claim 1, characterized in that, The mass ratio of Co to CeO2 / γ-Al2O3 is 0.5% to 1%.

4. The method for catalyzing propane dehydrogenation to propylene using a CoCe composite oxide catalyst according to claim 1, characterized in that, The preparation method of the CoCe composite oxide catalyst includes the following steps: (1) Ce precursor solution A was prepared using Ce(NO3)3·6H2O. Precursor solution A was added dropwise to γ-Al2O3 powder. After shaking and sonication, a mud-like mixture was obtained. The mud-like mixture was dried, ground into powder, and calcined at 400℃~700℃ for 1~6h. The obtained product was denoted as CeO2 / γ-Al2O3. When solution A is added dropwise to γ-Al2O3, the ratio of the volume of solution A in mL to the mass of the carrier γ-Al2O3 in g is controlled to be 1:1 to 4:

1. (2) A precursor solution B of Co was prepared using Co(NO3)2·6H2O. The precursor solution B was added dropwise to the CeO2 / γ-Al2O3 powder obtained in step (1). After shaking and sonication, a slurry-like mixture was obtained. The slurry-like mixture was dried, ground into powder, and calcined at 400-700℃ for 1-6 h. The resulting catalyst was denoted as CoO-CeO2 / γ-Al2O3. When adding solution B dropwise to CeO2 / γ-Al2O3, the ratio of the volume of solution B in mL to the mass of CeO2 / γ-Al2O3 in g is controlled to be 1:1 to 4:

1.

5. The method for catalyzing propane dehydrogenation to propylene using a CoCe composite oxide catalyst according to claim 4, characterized in that, In steps (1) and (2), the drying is carried out in flowing air at 50℃~110℃ for 6~18h.

6. In the method for producing propylene from propane by catalytic dehydrogenation using a CoCe composite oxide catalyst according to claim 4, in steps (1) and (2), the calcination temperature is 500℃~600℃ and the time is 2~4h.

7. The method for producing propylene from propane via CoCe composite oxide catalyst according to claim 4, characterized in that, In step (1), when adding solution A dropwise to γ-Al2O3, the ratio of the volume of solution A in mL to the mass of the carrier γ-Al2O3 in g is controlled to be 2:1 to 3:

1.

8. The method for catalyzing propane dehydrogenation to propylene using a CoCe composite oxide catalyst according to claim 4, characterized in that, In step (2), when adding solution B dropwise to CeO2 / γ-Al2O3, the ratio of the volume of solution B in mL to the mass of CeO2 / γ-Al2O3 in g is controlled to be 1.2:1 to 2:

1.

9. The method for catalyzing propane dehydrogenation to propylene using a CoCe composite oxide catalyst according to claim 1, characterized in that, Under a total pressure of 0.1–0.12 MPa, a propane atmosphere of 15–30 kPa, and a temperature of 570–590 °C, for 1–2 hours... -1 Reactions under weight-space velocity conditions.

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