Calcium-based bifunctional material integrating carbon capture and hydro-conversion as well as preparation method and application of calcium-based bifunctional material

Abstract

The invention relates to the technical field of integrated carbon dioxide capture and hydro-conversion, and discloses a calcium-based bifunctional material integrated with carbon capture and hydro-conversion as well as a preparation method and application of the calcium-based bifunctional material. The invention relates to a calcium-based bifunctional material integrating carbon capture and hydro-conversion and a preparation method thereof. The calcium-based bifunctional material is mainly composed of an adsorbent matrix and a catalyst matrix, a proper calcium precursor, an adsorbent support and an RWGS catalyst are selected, the adsorbent matrix, the catalyst matrix and a dispersing agent are mixed, then water bath heating, stirring, drying and calcining are performed, and the calcium-based bifunctional material is obtained. The calcium-based bifunctional material for integrating carbon capture-hydro-conversion is obtained. Under the working conditions of normal pressure and 650 DEG C, compared with the traditional calcium-based CO2 adsorbent and hydro-conversion catalyst, the calcium-based CO2 adsorbent and hydro-conversion catalyst show higher CO2 adsorption capacity, CO2 conversion rate and better cycle stability in ICCU-RWGS reaction.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated carbon dioxide capture and hydrogenation conversion, and particularly relates to a calcium-based bifunctional material for integrated carbon capture-hydrogenation conversion, a preparation method thereof, and an application thereof. Background Art

[0002] With the acceleration of the global industrialization process, the continuous increase in carbon dioxide (CO2) emissions has had an increasingly serious impact on the environment and climate. How to effectively capture and utilize CO2 has become a focus issue of global concern. Among many technologies, the integrated CO2 capture and utilization (ICCU) technology has shown broad application prospects because it can simultaneously achieve CO2 emission reduction and resource utilization.

[0003] The ICCU technology combines CO2 capture and conversion reactions, and completes the adsorption and conversion of CO2 in the same reactor, effectively reducing energy consumption and equipment costs. Among them, the reverse water gas shift reaction (RWGS) is an important CO2 conversion pathway, which can convert CO2 into syngas (mainly composed of carbon monoxide and hydrogen), providing raw materials for subsequent chemical synthesis.

[0004] As a common CO2 adsorption material, calcium-based adsorbents have been widely used in the ICCU technology due to their low price, large adsorption capacity and other advantages. However, traditional calcium-based adsorbents have poor CO2 adsorption performance at high temperatures and are prone to deactivation during cyclic use. To solve these problems, calcium-based bifunctional materials have emerged. By combining calcium-based adsorbents with catalysts, calcium-based bifunctional materials can not only effectively improve the CO2 adsorption performance, but also promote the RWGS reaction to achieve efficient CO2 capture and conversion.

[0005] In recent years, researchers have made significant progress in the preparation and application of calcium-based bifunctional materials. For example, by introducing different carrier materials, such as cerium oxide, titanium oxide, etc., the CO2 adsorption performance and thermal stability of calcium-based adsorbents can be significantly improved. In addition, by compounding calcium-based adsorbents with metal catalysts such as nickel and copper, the RWGS reaction can be effectively promoted, and the yield and purity of syngas can be increased.

[0006] However, at present, calcium-based bifunctional materials still face some challenges in practical applications. For example, the cyclic stability of the materials needs to be further improved, and more research is needed on the optimization of reaction conditions. Therefore, the development of high-performance calcium-based bifunctional materials is of great significance for promoting the practical application of the ICCU-RWGS technology. Summary of the Invention

[0007] The object of the present invention is: based on the above technical problems, to provide a calcium-based bifunctional material integrating carbon capture-hydrogenation conversion, and its preparation method and application.

[0008] To achieve the above object, the first aspect of the present invention provides a preparation method of a calcium-based bifunctional material integrating carbon capture-hydrogenation conversion, the method comprising the following steps:

[0009] (1) Mix an adsorbent matrix, a catalyst matrix, and deionized water to obtain a mixed solution;

[0010] (2) Perform a water bath heating treatment on the mixed solution, and stir until a honey-like wet gel is obtained;

[0011] (3) Place the honey-like wet gel at 120-150 °C for drying for 3-4 h to obtain a fibrous dry gel;

[0012] (4) Place the fibrous dry gel in a muffle furnace, first heat it at 250-300 °C for 2 h, then raise the temperature to 800-850 °C, and calcine at this temperature for 3 h, and grind to obtain a calcium-based bifunctional material integrating carbon capture-hydrogenation conversion.

[0013] The second aspect of the present invention provides a calcium-based bifunctional material integrating carbon capture-hydrogenation conversion prepared by the method described in the first aspect of the present invention.

[0014] The third aspect of the present invention provides the application of the calcium-based bifunctional material integrating carbon capture-hydrogenation conversion described in the second aspect of the present invention in the capture and hydrogenation conversion of CO2.

[0015] The calcium-based bifunctional material integrating carbon capture-hydrogenation conversion, its preparation method and application provided by the present invention at least further have the following beneficial effects:

[0016] (1) In the present invention, the addition of Mn has a good promoting effect on the cyclic stability of the ICCU-RWGS process of the bifunctional material; the addition of Fe can improve the CO2 adsorption capacity of the bifunctional material to a certain extent during the carbon capture process; the introduction of Ni and Ce can further improve the CO2 conversion rate of the bifunctional material during the hydrogenation conversion process. In 10 cycles, the cumulative CO2 capture amount of the bifunctional material prepared in the embodiment of the present invention is 92.894 mmol / g, the total attenuation rate of the adsorption capacity is 18.16%, and the average conversion rate is 57.8%.

[0017] (2) Compared with commercial CaO, the CO2 adsorption capacity is higher, and the CO2 hydrogenation conversion rate can reach the average level of the reported RWGS catalysts. Description of the Drawings

[0018] Figure 1It is the flow chart for preparing the calcium-based bifunctional material integrating carbon capture and hydrogenation conversion in the embodiments of the present invention;

[0019] Figure 2 It is the comparison chart of CO2 capture amounts during the cyclic performance test of the materials obtained in the embodiments and comparative examples of the present invention for CO2 capture;

[0020] Figure 3 It is the comparison chart of CO yields during the cyclic performance test of the materials obtained in the embodiments and comparative examples of the present invention for CO2 capture;

[0021] Figure 4 It is the comparison chart of CO2 conversion rates during the cyclic performance test of the materials obtained in the embodiments and comparative examples of the present invention for CO2 capture. Specific embodiments

[0022] In the ranges disclosed herein, the endpoints and any values are not limited to the exact ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values, they can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein.

[0023] As described above, the first aspect of the present invention provides a preparation method of a calcium-based bifunctional material integrating carbon capture and hydrogenation conversion, and the method includes the following steps:

[0024] (1) Mix an adsorbent matrix, a catalyst matrix, and deionized water to obtain a mixed solution;

[0025] (2) Perform a water bath heating treatment on the mixed solution and stir until a honey-like wet gel is obtained;

[0026] (3) Place the honey-like wet gel at 120 - 150 °C for drying for 3 - 4 h to obtain a fibrous dry gel;

[0027] (4) Place the fibrous dry gel in a muffle furnace, first heat it at 250 - 300 °C for 2 h, then raise the temperature to 800 - 850 °C, and calcine at this temperature for 3 h, and grind to obtain the calcium-based bifunctional material integrating carbon capture and hydrogenation conversion.

[0028] In the present invention, deionized water is used as a dispersant, which has good dissolution and complexation effects on the adsorbent matrix and the catalyst matrix.

[0029] In the present invention, for inorganic calcium precursors, citric acid with a total molar ratio of 1:1 to metal ions needs to be added as a complexing agent, and for organic calcium precursors, no additional complexing agent is added.

[0030] In the present invention, in step (1), during the water bath and stirring heating process, the mixed solution is clear and transparent without precipitation.

[0031] Preferably, in step (1), the adsorbent matrix is composed of a calcium precursor and an adsorbent support.

[0032] More preferably, in step (1), the calcium precursor is calcium citrate or calcium gluconate, preferably C 12 H 22 O 14 Ca.

[0033] Preferably, in step (1), the adsorbent support is a nitrate containing Fe or a nitrate containing Mn.

[0034] Preferably, in step (1), in the adsorbent matrix, the molar amount of Fe element is 0 - 10 wt% of the molar amount of the calcium precursor.

[0035] More preferably, in step (1), in the adsorbent matrix, the molar amount of Mn element is 0 - 10 wt% of the molar amount of the calcium precursor.

[0036] Preferably, in step (1), the catalyst matrix is a metal compound containing Ni or a metal compound containing Ce.

[0037] More preferably, in step (1), in the catalyst matrix, the mass fraction of Ni element is 5 - 10 wt% of the CaO theoretically formed by the calcination of the calcium precursor.

[0038] Preferably, in step (1), in the catalyst matrix, the mass fraction of Ce element is 5 - 10 wt% of the CaO theoretically formed by the calcination of the calcium precursor.

[0039] Preferably, in step (1), the catalyst matrix is a RWGS catalyst, and the RWGS catalyst is Ni(NO3)2·9H2O and / or Ce(NO3)4.

[0040] Preferably, in step (1), the molar ratio of the amounts used of the adsorbent matrix, the catalyst matrix, and the deionized water is 100:5 - 20:400 - 600.

[0041] More preferably, in step (2), the conditions of the water bath heating treatment are satisfied: the temperature is 80 - 90 °C, and the time is 3 - 6 h.

[0042] As described above, the second aspect of the present invention provides a calcium-based bifunctional material for integrated carbon capture - hydrogenation conversion prepared by the method of the first aspect of the present invention.

[0043] As described above, the third aspect of the present invention provides the application of the calcium-based bifunctional material integrating carbon capture-hydrogenation conversion described in the second aspect of the present invention in the capture and hydrogenation conversion of CO2.

[0044] The present invention will be described in detail below through examples. In the following examples, unless otherwise specified, the raw materials are commercially available products.

[0045] Example 1

[0046] This example is used to Figure 1 provide a method for preparing a calcium-based bifunctional material integrating carbon capture-hydrogenation conversion, and the method includes the following steps:

[0047] (1) Weigh 5.594 g of C 12 H 22 O 14 Ca, 0.104 g of Mn(NO3)2·4H2O (the addition amount is 3 wt% of the molar amount of CaO), 0.329 g of Fe(NO3)3·9H2O (the addition amount is 7 wt% of the molar amount of CaO), 0.347 g of Ni(NO3)2·9H2O (the addition amount is 10 wt% of the molar amount of CaO), 0.242 g of Ce(NO3)4 (the addition amount is 5 wt% of the molar amount of CaO) and place them in a beaker, then add 22.456 g of deionized water, and stir with a magnetic stirrer to obtain an emulsion-like mixed solution.

[0048] (2) Add a magnetic stir bar to the beaker containing the emulsion-like mixed solution, and then transfer it to a water bath magnetic stirrer. Hydrothermally stir at 90 °C for 3 h to obtain a honey-like wet gel.

[0049] (3) Take out the magnetic stir bar in the beaker in step (2), transfer it to a forced air drying oven, and dry at 150 °C for 3 h to obtain a fibrous dry gel.

[0050] (4) Place the fibrous dry gel in a muffle furnace, first heat at 270 °C for 2 h, then increase the temperature to 850 °C at a rate of 5 °C / min, and calcine at this temperature for 3 h, and grind to obtain a calcium-based bifunctional material, denoted as Mn-CaO.

[0051] Example 2

[0052] Carry out according to the method in Example 1, except that in step (1), Ce(NO3)4 is not added, and the remaining steps and parameters are the same as those in Example 1.

[0053] Example 3

[0054] It was carried out according to the method in Example 1, except that in step (1), Ni(NO3)2·9H2O was not added, and the remaining steps and parameters were the same as those in Example 1.

[0055] Comparative Example 1

[0056] It was carried out according to the method in Example 1, except that in step (1), Fe(NO3)3·9H2O, Ni(NO3)2·9H2O, and Ce(NO3)4 were not added, and the amount of Mn(NO3)2·4H2O used was 0.347 g (the addition amount was 10 wt% of the molar amount of CaO), and the remaining steps and parameters were the same as those in Example 1.

[0057] Comparative Example 2

[0058] It was carried out according to the method in Example 1, except that in step (1), Ni(NO3)2·9H2O and Ce(NO3)4 were not added, and the remaining steps and parameters were the same as those in Example 1.

[0059] Comparative Example 3

[0060] It was carried out according to the method in Example 1, except that in step (1), the Mn(NO3)2·4H2O, Fe(NO3)3·9H2O, Ni(NO3)2·9H2O, and Ce(NO3)4 were not added, and the remaining steps and parameters were the same as those in Example 1. Among them, the prepared material was denoted as CG-CaO.

[0061] Test Example

[0062] The ICCU-RWGS performance tests were carried out on the materials prepared in the examples and comparative examples, and the results are as Figures 2 to 4 shown.

[0063] Among them, the ICCU-RWGS performance test process is as follows:

[0064] The test temperature was 650 °C; a fixed-bed reactor was used. The CO2 capture process time was 20 min, and a mixed gas of 100 mL / min of 15 Vol.% CO2 / Ar was introduced to simulate flue gas for carbon capture; after carbon capture, it was changed to 100 mL / min of 15 Vol.% H2 for the RWGS process;

[0065] During the test, the CO2 capture amount (denoted as ), the CO production amount (denoted as Q CO ), and the CO2 conversion rate (denoted as X CO2 ) were calculated according to the following formulas:

[0066]

[0067] Wherein, F represents the volume flow rate of the gas, and t represents time.

[0068] It can be seen from Figures 2 to 4 that the addition of Mn has a good promoting effect on the cyclic stability of the bifunctional material in the ICCU-RWGS process; the addition of Fe can improve the CO2 adsorption capacity of the bifunctional material in the carbon capture process to a certain extent; the introduction of Ni and Ce can further improve the CO2 conversion rate of the bifunctional material in the hydrogenation conversion process. In 10 cycles, the cumulative CO2 capture amount of the bifunctional material prepared in Example 5 of the present invention is 92.894 mmol / g, the total attenuation rate of the adsorption capacity is 18.16% (35.29% higher than that of the comparative example), and the average conversion rate is 57.8% (16.1% higher than that of the comparative example).

[0069] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any other suitable combination of each technical feature. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.

Claims

1. A preparation method of a calcium-based bifunctional material integrating carbon capture and hydrogenation conversion, characterized in that, The method comprises the following steps: (1) Mix an adsorbent matrix, a catalyst matrix, and deionized water to obtain a mixed solution; (2) Perform a water bath heating treatment on the mixed solution and stir until a honey-like wet gel is obtained; (3) Dry the honey-like wet gel at 120 - 150 °C for 3 - 4 h to obtain a fibrous dry gel; (4) Place the fibrous dry gel in a muffle furnace, first heat it at 250 - 300 °C for 2 h, then raise the temperature to 800 - 850 °C, and calcine it at this temperature for 3 h, and grind it to obtain a calcium-based bifunctional material for integrated carbon capture - hydrogenation conversion.

2. The method according to claim 1, characterized in that In step (1), the adsorbent matrix is composed of a calcium precursor and an adsorbent support.

3. The method according to claim 2, wherein In step (1), the calcium precursor is calcium citrate or calcium gluconate, preferably C 12 H 22 O 14 Ca.

4. The method according to claim 2, characterized in that, In step (1), the adsorbent support is a nitrate containing Fe or a nitrate containing Mn.

5. The method according to any one of claims 2 to 4, characterized in that, In step (1), in the adsorbent matrix, the molar amount of Fe element is 0 - 10 wt% of the molar amount of the calcium precursor; And / or, in step (1), in the adsorbent matrix, the molar amount of Mn element is 0 - 10 wt% of the molar amount of the calcium precursor.

6. The method according to claim 1 or 2, characterized in that, In step (1), the catalyst matrix is a metal compound containing Ni or a metal compound containing Ce; And / or, in step (1), in the catalyst matrix, the mass fraction of Ni element is 5 - 10 wt% of the theoretically formed CaO by calcining the calcium precursor; And / or, in step (1), in the catalyst matrix, the mass fraction of Ce element is 5 - 10 wt% of the theoretically formed CaO by calcining the calcium precursor; And / or, in step (1), the catalyst matrix is a RWGS catalyst, and the RWGS catalyst is Ni(NO3)2·9H2O and / or Ce(NO3)4.

7. The method according to claim 1 or 2, characterized in that In step (1), the molar ratio of the amounts of the adsorbent matrix, the catalyst matrix, and the deionized water is 100:5 - 20:400 - 600.

8. The method according to claim 1 or 2, characterized in that, In step (2), the conditions of the water bath heating treatment are satisfied: the temperature is 80 - 90 °C and the time is 3 - 6 h.

9. A calcium-based bifunctional material for integrated carbon capture - hydrogenation conversion prepared by the method according to any one of claims 1 - 8.

10. Use of the calcium-based bifunctional material for integrated carbon capture - hydrogenation conversion according to claim 9 in the capture and hydrogenation conversion of CO2.

Images