WO2023103823A1 - Pt-ce dehydrogenation catalytic material, preparation method, and application thereof - Google Patents

Abstract

The invention relates to a Pt-Ce dehydrogenation catalytic material, a preparation method, and an application thereof. The catalytic material comprises a γ-Al₂O₃ carrier and an active ingredient loaded on the γ-Al₂O₃ carrier. The active ingredient is a Pt-Ce composition. The scheme of the present invention has the advantages of a simple composition, low costs, low active ingredient consumption, excellent dehydrogenation performance, high catalytic activity, and a reduction in dehydrogenation energy consumption.

Description

Pt-Ce dehydrogenation catalytic material, preparation method and application

The present invention claims the priority of the Chinese patent application with the application number 2021114816636 and the title of the invention "Pt-Ce dehydrogenation catalytic material, preparation method and application" submitted to the China Patent Office on December 06, 2021. All of the application The contents are incorporated herein by reference.

technical field

The invention relates to new energy liquid hydrogen storage and dehydrogenation technology, in particular to a Pt-Ce dehydrogenation catalytic material, a preparation method and an application thereof.

Background technique

Fossil energy is inefficient, has limited reserves, and is prone to problems such as environmental pollution and the greenhouse effect. It is very important for the sustainable development of human society to seek low-carbon emission, efficient and clean new energy sources to replace traditional fossil energy sources such as coal and oil. Hydrogen energy is one of the main new energy sources in the 21st century. It has rich sources, excellent combustion performance, good economic benefits, high energy density, green environmental protection, safety and efficiency, and is an ideal energy carrier.

Hydrogen storage is a key link in the utilization of hydrogen energy. Currently researched hydrogen storage technologies include high-pressure hydrogen storage, liquid hydrogen storage, solid-state hydrogen storage, liquid-phase organic hydrogen carrier hydrogen storage, etc. The first three hydrogen storage methods have problems such as excessive energy consumption, high gasification rate, and safety. And subject to factors such as cost, reversible characteristics, and stability, it is difficult to fit with existing infrastructure, and large-scale applications are limited. Liquid-phase organic hydrogen carrier hydrogen storage is to realize the storage and release of hydrogen through the hydrogenation and dehydrogenation reactions of unsaturated organic substances, and realize the transportation and application of hydrogen energy in different places. Because the nature of the hydrogen carrier is similar to that of fuel oil, it can be transported by using or transforming the existing basic oil transportation equipment. The form of hydrogen storage is safe and efficient, and it has a good market development prospect.

Hydrogen carriers currently being researched or commercially available include toluene, benzyltoluene (MBT), dibenzyltoluene (DBT), benzylbenzene, and N-ethylcarbazole (NEC). Catalytic dehydrogenation is realized in the system, which is convenient for transportation in liquid form. DBT is a heat transfer oil for industrial applications. It has a high and stable boiling point, and its low vapor pressure can also ensure the high purity of the product hydrogen. In addition, the low cost of DBT also determines that it has more advantages in bulk hydrogen storage and transportation. The existing dehydrogenation catalytic materials have complex active components, large amounts of precious metals, and various types, which have extremely high application costs.

The information disclosed in this Background section is only intended to increase the understanding of the general background of the present invention and should not be considered as an acknowledgment or any form of suggestion that the information constitutes the prior art that is already known to those of ordinary skill in the art.

Contents of the invention

The purpose of the present invention is to provide a Pt-Ce dehydrogenation catalytic material, preparation method and application thereof, which have higher dehydrogenation performance, greatly improved catalytic activity and reduced dehydrogenation energy consumption.

In order to achieve the above object, an embodiment of the present invention provides a Pt-Ce dehydrogenation catalytic material, including a gamma-Al ₂ O ₃ carrier; and an active ingredient loaded on the gamma-Al ₂ O ₃ carrier, the active ingredient It is a Pt-Ce composition.

In one or more embodiments of the present invention, the γ-Al ₂ O ₃ carrier is a 40-60 mesh granular material.

In one or more embodiments of the present invention, the loading amount of Pt on the γ-Al ₂ O ₃ carrier in the Pt-Ce composition is 0.3-0.6 wt.%, and the loading amount of Ce on the γ-Al ₂ O ₃ carrier The loading is 0.125-0.75 wt.%.

In one or more embodiments of the present invention, the mass ratio in the Pt-Ce composition satisfies: Pt:Ce=1:(0.25-1.5).

In one or more embodiments of the present invention, the preparation method of Pt-Ce dehydrogenation catalytic material includes the following steps: preparing γ-Al ₂ O ₃ carrier, and preparing active precursor solution with platinum source and/or cerium source ; After co-impregnating the γ-Al ₂ O ₃ carrier and the active precursor solution, aging, drying and calcining, the Pt-Ce dehydrogenation catalytic material is obtained. Preferably, the drying conditions may be as follows: the temperature may be selected at 100-130°C. The drying time can be selected from 8-20h.

In one or more embodiments of the present invention, the precursor solution is one of the following situations: A, a platinum source precursor solution and a cerium source precursor solution; B, a mixed precursor solution containing a mixture of a platinum source and a cerium source.

In one or more embodiments of the present invention, the co-impregnation means that the γ-Al ₂ O ₃ carrier is stirred with the active precursor solution for 20-40 minutes, and then aged for 18-36 hours.

In one or more embodiments of the present invention, the calcination is performed under a hydrogen atmosphere for 3-8 hours, and the calcination temperature is 300-400°C.

In one or more embodiments of the present invention, the hydrogen atmosphere is such that the hydrogen flow rate is 40-60 mL/min.

In one or more embodiments of the present invention, the application of Pt-Ce dehydrogenation catalytic material in catalytic dehydrogenation of hydrogen storage material.

Compared with the prior art, according to the Pt-Ce dehydrogenation catalytic material, preparation method and application thereof according to the embodiments of the present invention, the traditional dehydrogenation catalyst for perhydrodibenzyltoluene (18H-DBT) has slow dehydrogenation rate, OH-DBT low selectivity and low dehydrogenation conversion. The invention selectively adopts Pt-Ce double-supported catalysts, and the two synergistically promote the progress of the dehydrogenation reaction and improve the catalytic efficiency.

The present invention can realize the catalytic dehydrogenation of the DBT hydrogenation product in a liquid system, which is convenient for transportation, storage and application promotion in liquid form, and reduces the cost of popularization and application. In addition, DBT is a heat transfer oil for industrial applications, with a high and stable boiling point, and its low vapor pressure can also ensure the high purity of the product hydrogen. Finally, the low cost of DBT also determines that it has more advantages in bulk hydrogen storage and transportation.

Compared with existing catalysts, this scheme selectively realizes Pt-Ce synergistic catalytic dehydrogenation reaction, improves product selectivity, catalytic dehydrogenation rate, achieves a substantial increase in dehydrogenation efficiency, and has higher dehydrogenation performance , greatly improving the catalytic activity and reducing the energy consumption of dehydrogenation.

Description of drawings

Fig. 1 is the XRD spectrogram of the Pt-Ce/ _Al2O3 catalyst of different proportions according to one embodiment of _the present invention;

Fig. 2 is according to the Pt-Ce/ _Al2O3 catalyst of different proportions according to an embodiment of _the present invention H in catalytic dehydrogenation process Cumulative flow curve;

Fig. 3 is a GC-MS spectrum of the hydrogen carrier after the catalytic dehydrogenation of the 0.5%Pt-0.25%Ce/Al ₂ O ₃ catalyst according to an embodiment of the present invention.

Detailed ways

The specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

Unless expressly stated otherwise, throughout the specification and claims, the term "comprise" or variations thereof such as "includes" or "includes" and the like will be understood to include the stated elements or constituents, and not Other elements or other components are not excluded.

The nature of the hydrogen carrier used in liquid-phase organic hydrogen carrier hydrogen storage is similar to that of fuel oil, and the existing oil-based transportation equipment can be used or modified for transportation. The hydrogen storage form is safe and efficient, and it is different from traditional high-pressure hydrogen storage, liquid hydrogen storage and solid-state storage Compared with hydrogen, it has better market development prospects and is the key focus in the field of new energy today.

In the following examples, including but not limited to, the catalytic dehydrogenation of the hydrogenated product shown in the following reaction scheme can be used as an example to illustrate the advantages of the present invention, but it is not as a limitation to the scope of the present invention: liquid phase organic matter It is the full hydrogenation product 18H-DBT of dibenzyltoluene (DBT). Using Pt-Ce/Al ₂ O ₃ as a dehydrogenation catalyst, 18H-DBT is catalyzed for dehydrogenation reaction at normal pressure and below 350°C.

Example group 1

Reaction equipment: high-temperature and high-pressure reactor, the left and right ends of the reactor are equipped with inlet and outlet pipes and valves, and a mass flow meter is installed in the bypass of the outlet pipe to record the hydrogen flow rate at the outlet. The temperature, pressure, and time parameters of the reactor and the flow and time parameters of the mass flow meter can be transmitted to the computer for collection through the data line. In addition, in order to ensure that the organic matter does not gasify during the reaction, a 20cm-long condensation pipe is installed on the top of the reactor cover.

Catalyst preparation:

The purchased γ-Al ₂ O ₃ is used as the carrier, and before loading, 40-50 mesh γ-Al ₂ O ₃ is screened for use.

Add a certain amount of ultrapure water to chloroplatinic acid (H ₂ PtCl ₆ ) and cerium nitrate (Ce(NO ₃ ) ₃ 6H ₂ O) to prepare a mixed solution of corresponding concentration (the concentration here can be selected depending on the blending Depending on the loading requirements of the carrier, it can be prepared as a mixed solution of 0.5M Pt and 0.5M Ce, and other feasible concentration values can be selected from the range of 0.1-1M, such as 0.125M, 0.25M, 0.75M, etc., the same below) , ultrasonic dispersion for 20min;

The catalyst is prepared by the co-impregnation method, and the above mixed solution is poured into an appropriate amount of γ-Al ₂ O ₃ , for example, the mixed solution and the carrier are mixed at a volume ratio of 1:1, and then aged after stirring for 30 minutes (stand at room temperature, the same below) After 24 hours, centrifuge, wash, and dry overnight at 120°C in a vacuum oven;

The above-mentioned dried product was placed in a tube furnace and calcined for 5 hours under a hydrogen atmosphere. The calcining temperature was 350° C., and the heating rate was 5° C./min (referring to the heating rate from room temperature to 350° C., the same below), and the hydrogen flow rate was 40mL/min, after calcination, the target catalyst Pt-Ce/Al ₂ O ₃ is obtained, that is, a 0.5%Pt-0.50%Ce/Al ₂ O ₃ catalytic material is obtained, and other serial numbers can be obtained in the same way.

Dehydrogenation reaction process:

Feeding: Add 40g of 18H-DBT organic liquid oil and 2g of Pt-Ce/Al ₂ O ₃ catalyst into the reactor;

Pressure keeping: After installing the reactor, fill it with 1-2MPa nitrogen and keep the pressure for 30 minutes. If the pressure remains unchanged, it is considered as airtight;

Replacement: Evacuate the pressure-holding nitrogen, and replace it with nitrogen and hydrogen (1-2MPa) 2-3 times each to ensure that the air in the kettle is completely emptied;

Heating: Close the inlet and outlet pipe valves of the reactor, set the temperature to 350°C (that is, the highest reaction temperature of this scheme, as shown in the table below, the same below), and start the operation at a stirring speed of 1000rpm;

Response: When the temperature rises to 150°C, open the gas outlet and the valve connected to the bypass flowmeter, and if the flowmeter reads, it means that the dehydrogenation starts;

End: When the mass flow meter reads 0, stop running and the reaction ends.

The advantages of this embodiment are described below in conjunction with Figures 1-3:

As shown in Figure 1, it can be seen from the XRD spectrum analysis that only the diffraction peaks of the carrier Al ₂ O ₃ are shown in the figure. On the one hand, it is because the metal content of Pt and Ce is low, and on the other hand, it shows that the two metals are on the carrier. Disperse evenly without agglomeration.

Table 1 Dehydrogenation temperature and reaction time of Pt-Ce/Al ₂ O ₃ catalysts with different proportions

serial number	catalyst	Dehydrogenation temperature/℃	Dehydrogenation time/min
1	0.5%Pt/Al 2 O 3	220～350	90
2	0.5%Pt-0.125%Ce / Al2O3	180～350	75
3	0.5%Pt-0.25%Ce / Al2O3	160～350	41
4	0.5%Pt-0.50%Ce / Al2O3	175～350	49
5	0.5%Pt-0.75%Ce / Al2O3	175～350	53

Table 1 and Figure 2 show that the catalyst material of the present invention has obvious improvements in dehydrogenation temperature and dehydrogenation efficiency.

As shown in Figure 3, the GC-MS spectrogram analysis results of the hydrogen carrier after catalytic dehydrogenation of 0.5%Pt-0.25%Ce/Al ₂ O ₃ catalyst: because the catalysts with different ratios are almost all dehydrogenated completely, only the above ratio Take the dehydrogenation results as an example, as shown in the figure below, the selectivity in the table is the analysis result of MS quantitative software, and the dehydrogenation conversion rate is the calculation result (calculated with OH-DBT as the final product).

Example group 2

Reaction equipment: high-temperature and high-pressure reaction kettle, the left and right ends of the reaction kettle are equipped with inlet and outlet pipes and valves, and a mass flow meter is installed in the bypass of the outlet pipe to record the hydrogen flow rate at the outlet. The temperature, pressure, and time parameters of the reactor and the flow and time parameters of the mass flow meter can be transmitted to the computer for collection through the data line. In addition, in order to ensure that the organic matter does not gasify during the reaction, a 20cm-long condensation pipe is installed on the top of the reactor cover.

Catalyst preparation:

The purchased γ-Al ₂ O ₃ is used as the carrier, and 50-60 mesh γ-Al ₂ O ₃ is sieved before loading, and is ready for use.

Using chloroplatinic acid (H ₂ PtCl ₆ ) aqueous solution and cerium nitrate (Ce(NO ₃ ) ₃ 6H ₂ O) as precursors, add a certain amount of ultrapure water to prepare a mixed solution of corresponding concentration, and ultrasonically disperse for 20 minutes;

The catalyst was prepared by the co-impregnation method. The above mixed solution was poured into a certain amount of γ-Al ₂ O ₃ , stirred for 20 minutes, aged for 30 hours, centrifuged, washed, and dried in a vacuum oven at 100°C for 8 hours;

The above dried product was placed in a tube furnace and calcined for 3 hours under a hydrogen atmosphere. The calcining temperature was 300°C, the heating rate was 5°C/min, and the hydrogen flow rate was 50mL/min. After calcining, the target catalyst Pt-Ce/Al was obtained ₂ O ₃ .

Dehydrogenation reaction process:

Feeding: Add 40g of 18H-DBT organic liquid oil and 2g of Pt-Ce/Al ₂ O ₃ catalyst into the reactor;

Pressure keeping: After installing the reactor, fill it with 1-2MPa nitrogen and keep the pressure for 30 minutes. If the pressure remains unchanged, it is considered as airtight;

Replacement: Evacuate the pressure-holding nitrogen, and replace it with nitrogen and hydrogen (1-2MPa) 2-3 times each to ensure that the air in the kettle is completely emptied;

Heating: Close the inlet and outlet pipe valves of the reactor, set the temperature to 350°C, stir at 1000rpm, and start running;

Reaction: When the temperature rises to 150°C, open the gas outlet and the valve connected to the flowmeter by the bypass, and when the temperature reaches 160-180°C, the flowmeter has a reading, and dehydrogenation begins;

End: When the mass flow meter reads 0, stop running and the reaction ends.

Table 2 Dehydrogenation temperature and reaction time of Pt-Ce/Al ₂ O ₃ catalysts with different proportions

serial number	catalyst	Dehydrogenation temperature/℃	Dehydrogenation time/min
1	0.5%Pt/Al 2 O 3	220～350	96

2	0.5%Pt-0.125%Ce / Al2O3	190～350	80
3	0.5%Pt-0.25%Ce / Al2O3	160～350	46
4	0.5%Pt-0.50%Ce / Al2O3	180～350	52
5	0.5%Pt-0.75%Ce / Al2O3	185～350	58

Table 2 shows that the catalyst material of the scheme of the present invention has obvious improvements in dehydrogenation temperature and dehydrogenation efficiency.

GC-MS spectrogram analysis results of the hydrogen carrier after catalytic dehydrogenation with 0.5% Pt-0.25% Ce/Al ₂ O ₃ catalyst: Since the catalysts with different ratios are almost completely dehydrogenated, only the above ratio is used as an example for dehydrogenation The results show, as shown in the following table, the selectivity in the table is the analysis result of MS quantitative software, and the dehydrogenation conversion is the calculation result (calculated with OH-DBT as the final product).

Example group 3

Reaction equipment: high-temperature and high-pressure reactor, the left and right ends of the reactor are equipped with inlet and outlet pipes and valves, and a mass flow meter is installed in the bypass of the outlet pipe to record the hydrogen flow rate at the outlet. The temperature, pressure, and time parameters of the reactor and the flow and time parameters of the mass flow meter can be transmitted to the computer for collection through the data line. In addition, in order to ensure that the organic matter does not gasify during the reaction, a 20cm-long condensation pipe is installed on the top of the reactor cover.

Catalyst preparation:

The purchased γ-Al ₂ O ₃ is used as the carrier, and 40-60 mesh γ-Al ₂ O ₃ is sieved before loading, and is ready for use.

Using chloroplatinic acid (H ₂ PtCl ₆ ) aqueous solution and cerium nitrate (Ce(NO ₃ ) ₃ 6H ₂ O) as precursors, add a certain amount of ultrapure water to prepare a mixed solution of corresponding concentration, and ultrasonically disperse for 20 minutes;

The catalyst was prepared by the co-impregnation method. The above mixed solution was poured into a certain amount of γ-Al ₂ O ₃ , stirred for 40 minutes, aged for 18 hours, centrifuged, washed, and dried in a vacuum oven at 130°C for 20 hours.

The above dried product was placed in a tube furnace and calcined for 6 hours under a hydrogen atmosphere. The calcining temperature was 400°C, the heating rate was 5°C/min, and the hydrogen flow rate was 60mL/min. After calcining, the target catalyst Pt-Ce/Al was obtained ₂ O ₃ .

Dehydrogenation reaction process:

Feeding: Add 40g of 18H-DBT organic liquid oil and 2g of Pt-Ce/Al ₂ O ₃ catalyst into the reactor;

Pressure keeping: After installing the reactor, fill it with 1-2MPa nitrogen and keep the pressure for 30 minutes. If the pressure remains unchanged, it is considered as airtight;

Replacement: Evacuate the pressure-holding nitrogen, and replace it with nitrogen and hydrogen (1-2MPa) 2-3 times each to ensure that the air in the kettle is completely emptied;

Heating: Close the inlet and outlet pipe valves of the reactor, set the temperature to 350°C, stir at 1000rpm, and start running;

Reaction: When the temperature rises to 150°C, open the gas outlet and the valve connected to the flowmeter by the bypass, and when the temperature reaches 160-180°C, the flowmeter has a reading, and dehydrogenation begins;

End: When the mass flow meter reads 0, stop running and the reaction ends.

Table 3 Dehydrogenation temperature and reaction time of Pt-Ce/Al ₂ O ₃ catalysts with different proportions

serial number	catalyst	Dehydrogenation temperature/℃	Dehydrogenation time/min
1	0.5%Pt/Al 2 O 3	220～350	86
2	0.5%Pt-0.125%Ce / Al2O3	175～350	73
3	0.5%Pt-0.25%Ce / Al2O3	155～350	38
4	0.5%Pt-0.50%Ce / Al2O3	175～350	45
5	0.5%Pt-0.75%Ce / Al2O3	180～350	55

Table 3 shows that the catalyst material of the present invention has obvious improvements in dehydrogenation temperature and dehydrogenation efficiency.

GC-MS spectrogram analysis results of the hydrogen carrier after catalytic dehydrogenation with 0.5% Pt-0.25% Ce/Al ₂ O ₃ catalyst: Since the catalysts with different ratios are almost completely dehydrogenated, only the above ratio is used as an example for dehydrogenation The results show, as shown in the table below, the selectivity in the table is the analysis result of MS quantitative software, and the dehydrogenation conversion is the calculation result (calculated with OH-DBT as the final product).

Example group 4

Reaction equipment: high-temperature and high-pressure reactor, the left and right ends of the reactor are equipped with inlet and outlet pipes and valves, and a mass flow meter is installed in the bypass of the outlet pipe to record the hydrogen flow rate at the outlet. The temperature, pressure, and time parameters of the reactor and the flow and time parameters of the mass flow meter can be transmitted to the computer for collection through the data line. In addition, in order to ensure that the organic matter does not gasify during the reaction, a 20cm-long condensation pipe is installed on the top of the reactor cover.

Catalyst preparation:

The purchased γ-Al ₂ O ₃ is used as the carrier, and 45-55 mesh γ-Al ₂ O ₃ is sieved before loading, and is ready for use.

Using chloroplatinic acid (H ₂ PtCl ₆ ) aqueous solution and cerium nitrate (Ce(NO ₃ ) ₃ 6H ₂ O) as precursors, add a certain amount of ultrapure water to prepare a mixed solution of corresponding concentration, and ultrasonically disperse for 20 minutes;

The catalyst was prepared by the co-impregnation method. The above mixed solution was poured into a certain amount of γ-Al ₂ O ₃ , stirred for 35 minutes, aged for 36 hours, centrifuged, washed, and dried in a vacuum oven at 110°C for 16 hours;

The above dried product was placed in a tube furnace and calcined for 8 hours under a hydrogen atmosphere. The calcining temperature was 380°C, the heating rate was 5°C/min, and the hydrogen flow rate was 55mL/min. After calcining, the target catalyst Pt-Ce/Al was obtained ₂ O ₃ .

Dehydrogenation reaction process:

Feeding: Add 40g of 18H-DBT organic liquid oil and 2g of Pt-Ce/Al ₂ O ₃ catalyst into the reactor;

Pressure keeping: After installing the reactor, fill it with 1-2MPa nitrogen and keep the pressure for 30 minutes. If the pressure remains unchanged, it is considered as airtight;

Replacement: Evacuate the pressure-holding nitrogen, and replace it with nitrogen and hydrogen (1-2MPa) 2-3 times each to ensure that the air in the kettle is completely emptied;

Heating: Close the inlet and outlet pipe valves of the reactor, set the temperature to 350°C, stir at 1000rpm, and start running;

Reaction: When the temperature rises to 150°C, open the gas outlet and the valve connected to the flowmeter by the bypass, and when the temperature reaches 160-180°C, the flowmeter has a reading, and dehydrogenation begins;

End: When the mass flow meter reads 0, stop running and the reaction ends.

Table 4 Dehydrogenation temperature and reaction time of Pt-Ce/Al ₂ O ₃ catalysts with different proportions

serial number	catalyst	Dehydrogenation temperature/℃	Dehydrogenation time/min
1	0.5%Pt/Al 2 O 3	220～350	95
2	0.5%Pt-0.125%Ce / Al2O3	190～350	72
3	0.5%Pt-0.25%Ce / Al2O3	165～350	43
4	0.5%Pt-0.50%Ce / Al2O3	170～350	48
5	0.5%Pt-0.75%Ce / Al2O3	175～350	54

Table 4 shows that the catalyst material of the present invention has obvious improvements in dehydrogenation temperature and dehydrogenation efficiency.

GC-MS spectrogram analysis results of the hydrogen carrier after catalytic dehydrogenation with 0.5% Pt-0.25% Ce/Al ₂ O ₃ catalyst: Since the catalysts with different ratios are almost completely dehydrogenated, only the above ratio is used as an example for dehydrogenation The results show, as shown in the table below, the selectivity in the table is the analysis result of MS quantitative software, and the dehydrogenation conversion is the calculation result (calculated with OH-DBT as the final product).

Comparative example group 1

Reaction equipment: high-temperature and high-pressure reactor, the left and right ends of the reactor are equipped with inlet and outlet pipes and valves, and a mass flow meter is installed in the bypass of the outlet pipe to record the hydrogen flow rate at the outlet. The temperature, pressure, and time parameters of the reactor and the flow and time parameters of the mass flow meter can be transmitted to the computer for collection through the data line. In addition, in order to ensure that the organic matter does not gasify during the reaction, a 20cm-long condensation pipe is installed on the top of the reactor cover.

Catalyst preparation:

The purchased porous material shown in Table 5 was used as the carrier, and before loading, the 40-50 mesh part was sieved for use.

Add a certain amount of ultrapure water to chloroplatinic acid (H ₂ PtCl ₆ ) and cerium nitrate (Ce(NO ₃ ) ₃ 6H ₂ O) to prepare a mixed solution of corresponding concentration (the concentration here can be selected depending on the blending Depending on the loading requirements of the carrier, it can be prepared as a mixed solution of 0.5M Pt and 0.5M Ce, and other feasible concentration values can be selected from the range of 0.1-1M, such as 0.125M, 0.25M, 0.75M, etc., the same below) , ultrasonic dispersion for 20min;

The catalyst is prepared by the co-impregnation method, and the above mixed solution is poured into an appropriate amount of carrier, such as the mixed solution and the carrier are mixed at a volume ratio of 1:1, aged for 24 hours after stirring for 30 minutes, centrifuged, washed, and placed in a vacuum drying oven for 120 ℃ dry overnight;

The above-mentioned dried product was placed in a tube furnace and calcined for 5 hours under a hydrogen atmosphere. The calcining temperature was 350°C, the heating rate was 5°C/min, and the hydrogen flow rate was 40mL/min. After calcining, the target catalyst Pt-Ce/Al was obtained ₂ O ₃ , that is, to obtain 0.5% Pt-0.50% Ce/carrier catalytic material, and the schemes of other serial numbers can be obtained in the same way.

Dehydrogenation reaction process:

Feeding: Add 40g of 18H-DBT organic liquid oil and 2g of Pt-Ce/carrier catalyst into the reactor;

Pressure keeping: After installing the reactor, fill it with 1-2MPa nitrogen and keep the pressure for 30 minutes. If the pressure remains unchanged, it is considered as airtight;

Replacement: Evacuate the pressure-holding nitrogen, and replace it with nitrogen and hydrogen (1-2MPa) 2-3 times each to ensure that the air in the kettle is completely emptied;

Heating: Close the inlet and outlet pipe valves of the reactor, set the temperature to 350°C (that is, the highest reaction temperature of this scheme, as shown in the table below, the same below), and start the operation at a stirring speed of 1000rpm;

Response: When the temperature rises to 150°C, open the gas outlet and the valve connected to the flowmeter in the bypass, and if the flowmeter reads, it means that the dehydrogenation starts;

End: When the mass flow meter reads 0, stop running and the reaction ends.

Table 5 Dehydrogenation temperature and reaction time of different proportions of Pt-Ce/support catalyst

GC-MS spectrogram analysis results of the hydrogen carrier after catalytic dehydrogenation of 0.5%Pt-0.25%Ce/zirconia catalyst: Since the catalysts with different proportions are almost completely dehydrogenated, only the above proportions are used as an example to show the dehydrogenation results. As shown in the table below, the selectivity in the table is the analysis result of MS quantitative software, and the dehydrogenation conversion rate is the calculation result (calculated with OH-DBT as the final product).

GC-MS spectrogram analysis results of the hydrogen carrier after catalytic dehydrogenation of 0.5%Pt-0.25%Ce/zeolite catalyst: Since the catalysts with different ratios are almost completely dehydrogenated, only the above ratio is used as an example to show the dehydrogenation results, as follows As shown in the table, the selectivity in the table is the analysis result of MS quantitative software, and the dehydrogenation conversion is the calculation result (calculating with OH-DBT as the final product).

GC-MS spectrogram analysis results of the hydrogen carrier after the catalytic dehydrogenation of 0.5%Pt-0.25%Ce/activated carbon catalyst: Since the catalysts with different ratios are almost completely dehydrogenated, the dehydrogenation results are shown only by taking the above ratio as an example, as follows As shown in the table, the selectivity in the table is the analysis result of MS quantitative software, and the dehydrogenation conversion is the calculation result (calculating with OH-DBT as the final product).

The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. These descriptions are not intended to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling others skilled in the art to make and use various exemplary embodiments of the invention, as well as various Choose and change. It is intended that the scope of the invention be defined by the claims and their equivalents.

Claims (10)

1. A kind of Pt-Ce dehydrogenation catalytic material, is characterized in that, comprises

   γ-Al ₂ O ₃ carrier;

   and the active ingredient loaded on the γ-Al ₂ O ₃ carrier, the active ingredient is a Pt-Ce composition.
2. The Pt-Ce dehydrogenation catalytic material according to claim 1, characterized in that the γ-Al ₂ O ₃ carrier is a 40-60 mesh particle material.
3. The Pt-Ce dehydrogenation catalytic material according to claim 1, characterized in that, in the Pt-Ce composition, the loading of Pt on the γ-Al ₂ O ₃ carrier is 0.3-0.6wt.%, and Ce is in The load on the γ-Al ₂ O ₃ carrier is 0.125-0.75wt.%.
4. The Pt-Ce dehydrogenation catalytic material according to claim 3, wherein the mass ratio in the Pt-Ce composition satisfies: Pt:Ce=1:(0.25-1.5).
5. The preparation method of the arbitrary described Pt-Ce dehydrogenation catalytic material as claimed in claim 1-4, comprises the steps:

   Prepare γ-Al ₂ O ₃ carrier, and prepare active precursor solution with platinum source and/or cerium source;

   After co-impregnating the γ-Al ₂ O ₃ carrier and the active precursor solution, aging, drying and calcining, the Pt-Ce dehydrogenation catalytic material is obtained.
6. The preparation method of Pt-Ce dehydrogenation catalytic material as claimed in claim 5, is characterized in that, described precursor solution is one of following situations:

   A, platinum source precursor solution and cerium source precursor solution;

   B. A mixed precursor solution containing a mixture of platinum source and cerium source.
7. The preparation method of Pt-Ce dehydrogenation catalytic material as claimed in claim 5, it is characterized in that, described co-impregnation is described gamma-Al ₂ O ₃ carrier and described active precursor solution after stirring 20-40min, aging 18-36h.
8. The preparation method of Pt-Ce dehydrogenation catalytic material according to claim 5, characterized in that, the calcination is 3-8h under hydrogen atmosphere, and the calcination temperature is 300-400°C.
9. The method for preparing a Pt-Ce dehydrogenation catalytic material according to claim 8, characterized in that, the hydrogen atmosphere is a hydrogen flow rate of 40-60 mL/min.
10. The application of the Pt-Ce dehydrogenation catalytic material as described in any one of claims 1-4 in the dehydrogenation of catalytic hydrogen storage materials.

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