Integrated carbon capture-hydroconversion calcium-based bifunctional material and preparation method and application thereof

Abstract

The application relates to the technical field of integrated carbon dioxide capture and hydrogenation conversion, and discloses a calcium-based bifunctional material for integrated carbon capture-hydrogenation conversion as well as a preparation method and application thereof. The calcium-based bifunctional material for integrated carbon capture-hydrogenation conversion and the preparation method. The calcium-based bifunctional material is mainly composed of an adsorbent matrix and a catalyst matrix, the adsorbent matrix, the catalyst matrix and a dispersing agent are mixed by selecting appropriate calcium precursors, adsorbent supports and RWGS catalysts, and then the mixture is subjected to water bath heating, stirring, drying and calcination to obtain the calcium-based bifunctional material for integrated carbon capture-hydrogenation conversion. Under the working condition of normal pressure and 650 DEG C, compared with traditional calcium-based CO2 adsorbents and hydrogenation conversion catalysts, the calcium-based bifunctional material has higher CO2 adsorption capacity, CO2 conversion rate and better cycle stability in the ICCU-RWGS reaction.

Description

Technical Field

[0001] This invention relates to the field of integrated carbon dioxide capture and hydrogenation conversion technology, specifically to a calcium-based bifunctional material integrating carbon capture and hydrogenation conversion, its preparation method, and its application. Background Technology

[0002] With the acceleration of global industrialization, the continuous rise 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 focal point of global concern. Among numerous technologies, Integrated CO2 Capture and Utilization (ICCU) technology shows broad application prospects due to its ability to simultaneously achieve CO2 emission reduction and resource utilization.

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

[0004] Calcium-based adsorbents are widely used in ICCU technology due to their low cost and large adsorption capacity. However, traditional calcium-based adsorbents exhibit poor CO2 adsorption performance at high temperatures and are prone to deactivation during recycling. To address these issues, bifunctional calcium-based materials have emerged. By combining calcium-based adsorbents with catalysts, these materials not only effectively improve CO2 adsorption performance but also promote RWGS reactions, achieving highly efficient CO2 capture and conversion.

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

[0006] However, calcium bifunctional materials still face some challenges in practical applications. For example, the cycling stability of the materials needs further improvement, and the optimization of reaction conditions requires more research. Therefore, developing high-performance calcium bifunctional materials is of great significance for promoting the practical application of ICCU-RWGS technology. Summary of the Invention

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

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

[0009] (1) Mix the adsorbent matrix, catalyst matrix and deionized water to obtain a mixture;

[0010] (2) The mixture is subjected to water bath heating treatment and stirred until a honey-like wet gel is obtained;

[0011] (3) The honey-like wet gel was dried at 120-150°C for 3-4 hours to obtain a fibrous dry gel.

[0012] (4) The fibrous dry gel is placed in a muffle furnace and heated at 250-300°C for 2 hours, then heated to 800-850°C and calcined at this temperature for 3 hours. After grinding, a calcium-based bifunctional material with integrated carbon capture-hydrogenation conversion is obtained.

[0013] A second aspect of the present invention provides a calcium-based bifunctional material with integrated 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 for integrated 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 with integrated carbon capture-hydrogenation conversion, its preparation method, and its application provided by this invention have at least the following beneficial effects:

[0016] (1) In this invention, the addition of Mn has a good promoting effect on the cycling 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 of the bifunctional material prepared in this embodiment of the invention was 92.894 mmol / g, the total adsorption capacity decay rate was 18.16%, and the average conversion rate was 57.8%.

[0017] (2) Compared with commercial CaO, CO2 has a higher adsorption capacity and the CO2 hydrogenation conversion rate can reach the average level of existing RWGS catalysts. Attached Figure Description

[0018] Figure 1This is a flowchart illustrating the preparation of calcium-based bifunctional materials integrating carbon capture-hydrogenation conversion according to an embodiment of the present invention;

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

[0020] Figure 3 This is a comparison chart of CO production during the CO2 capture cycle performance test of the materials obtained in the embodiments and comparative examples of the present invention;

[0021] Figure 4 This is a comparison chart of CO2 conversion rates during the CO2 capture cycle performance test of the materials obtained in the embodiments and comparative examples of the present invention. Detailed Implementation

[0022] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0023] As mentioned above, a first aspect of the present invention provides a method for preparing a calcium-based bifunctional material integrating carbon capture-hydrogenation conversion, the method comprising the following steps:

[0024] (1) Mix the adsorbent matrix, catalyst matrix and deionized water to obtain a mixture;

[0025] (2) The mixture is subjected to water bath heating treatment and stirred until a honey-like wet gel is obtained;

[0026] (3) The honey-like wet gel was dried at 120-150°C for 3-4 hours to obtain a fibrous dry gel.

[0027] (4) The fibrous dry gel is placed in a muffle furnace and heated at 250-300°C for 2 hours, then heated to 800-850°C and calcined at this temperature for 3 hours. After grinding, a calcium-based bifunctional material with integrated carbon capture-hydrogenation conversion is obtained.

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

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

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

[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] In a preferred embodiment, in step (1), the adsorbent support is a nitrate containing Fe or a nitrate containing Mn.

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

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

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

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

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

[0039] In a preferred embodiment, in step (1), the catalyst matrix is ​​an 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 adsorbent matrix, the catalyst matrix, and the deionized water is 100:5-20:400-600.

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

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

[0043] As previously stated, the third aspect of the present invention provides the application of the calcium-based bifunctional material for integrated 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 all commercially available products.

[0045] Example 1

[0046] This example is used for combination Figure 1 A method for preparing calcium-based bifunctional materials with integrated carbon capture-hydrogenation conversion is provided, and the method includes the following steps:

[0047] (1) Weigh out 5.594g of C 12 H 22 O 14 Ca, 0.104g Mn(NO3)2·4H2O (3wt% of the molar weight of CaO), 0.329g Fe(NO3)3·9H2O (7wt% of the molar weight of CaO), 0.347g Ni(NO3)2·9H2O (10wt% of the molar weight of CaO), and 0.242g Ce(NO3)4 (5wt% of the molar weight of CaO) were placed in a beaker, and then 22.456g of deionized water was added. The mixture was stirred with a magnetic stirrer to obtain an emulsion mixture.

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

[0049] (3) Take out the magnetic ball from the beaker in step (2) and transfer it to a forced-air drying oven. Dry it at 150°C for 3 hours to obtain a fibrous dry gel.

[0050] (4) The fibrous dry gel was placed in a muffle furnace and heated at 270°C for 2 hours. Then, the temperature was increased to 850°C at a rate of 5°C / min and calcined at this temperature for 3 hours. After grinding, a calcium-based bifunctional material was obtained, denoted as Mn-CaO.

[0051] Example 2

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

[0053] Example 3

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

[0055] Comparative Example 1

[0056] The procedure is 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 are not added, and the amount of Mn(NO3)2·4H2O is 0.347g (the amount added is 10wt% of the molar amount of CaO). The remaining steps and parameters are the same as in Example 1.

[0057] Comparative Example 2

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

[0059] Comparative Example 3

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

[0061] Test case

[0062] The materials prepared in the examples and comparative examples were subjected to ICCU-RWGS performance testing, and the results are as follows: Figures 2-4 As shown.

[0063] The ICCU-RWGS performance testing process is as follows:

[0064] The test temperature was 650℃; a fixed-bed reactor was used, and the CO2 capture process took 20 min. A mixed gas of CO2 / Ar with a concentration of 15 vol.% was introduced at a rate of 100 mL / min to simulate flue gas for carbon capture; after carbon capture, the process was changed to RWGS with a concentration of 15 vol.% H2 at a rate of 100 mL / min.

[0065] During the test, the CO2 capture amount (denoted as...) CO production (denoted as Q) CO CO2 conversion rate (denoted as X) CO2 The calculation formula for ) is as follows:

[0066]

[0067] In the formula, F represents the volumetric flow rate of the gas, and t represents time.

[0068] Depend on Figures 2-4 It can be seen that the addition of Mn has a good promoting effect on the cycling 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 bifunctional material prepared in Example 5 of this invention had a cumulative CO2 capture capacity of 92.894 mmol / g, a total adsorption capacity decay rate of 18.16% (35.29% higher than the comparative example), and an average conversion rate of 57.8% (16.1% higher than 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 inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for preparing an integrated carbon capture-hydroconversion calcium-based bifunctional material, characterized in that, The method comprises the following steps: (1) mixing an adsorbent base, a catalyst base and deionized water to obtain a mixed solution; (2) performing water bath heating treatment on the mixed solution and stirring until a honey-like wet gel is obtained; (3) drying the honey-like wet gel at 120-150 DEG C for 3-4 h to obtain a fibrous dry gel; (4) placing the fibrous dry gel in a muffle furnace, first heating at 250-300 DEG C for 2 h, then increasing the temperature to 800-850 DEG C and calcining at the temperature for 3 h, and grinding to obtain a calcium-based bifunctional material integrating carbon capture and hydroconversion; In step (1), the adsorbent base is composed of a calcium precursor and an adsorbent support; the calcium precursor is calcium citrate or calcium gluconate; the adsorbent support is a Fe-containing nitrate and / or a Mn-containing nitrate; In step (1), the catalyst base is a RWGS catalyst, and the RWGS catalyst is Ni(NO3)2·9H2O and / or Ce(NO3)4; In step (1), the adsorbent base, the catalyst base and the deionized water are used in a molar ratio of 100:5-20:400-600; The method does not additionally add a complexing agent.

2. The method of claim 1, wherein, In step (1), the calcium precursor is C 12 H 22 O 14 Ca.

3. The method according to claim 1 or 2, characterized in that, In step (1), in the adsorbent base, the molar amount of Fe element is 0-10wt% of the molar amount of the calcium precursor; And / or, in step (1), in the adsorbent base, the molar amount of Mn element is 0-10wt% of the molar amount of the calcium precursor.

4. The method according to claim 1 or 2, characterized in that, In step (1), in the catalyst base, the mass fraction of Ni element is 5-10wt% of the CaO theoretically formed by calcination of the calcium precursor; And / or, in step (1), in the catalyst base, the mass fraction of Ce element is 5-10wt% of the CaO theoretically formed by calcination of the calcium precursor.

5. The method according to claim 1 or 2, characterized in that, In step (2), the water bath heating treatment is performed under conditions of a temperature of 80-90 DEG C and a time of 3-6 h.

6. The calcium-based bifunctional material integrating carbon capture and hydroconversion prepared by the method of any one of claims 1-5.

7. Use of the calcium-based bifunctional material integrating carbon capture and hydroconversion of claim 6 in the capture and hydroconversion of CO2.

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