Ca / M Composite Material and Its Preparation and Application in Carbon Dioxide Reduction

Abstract

The present invention belongs to the field of carbon dioxide treatment, and specifically relates to a preparation method of a Ca / M composite material. A precursor is obtained by pre-reacting a Ca source, an M source and a complexing agent and then desolvating. The precursor is calcined at a temperature above 500 °C to obtain a precursor material. Then, the precursor material is thermally modified in a hydrogen-containing atmosphere to obtain the Ca / M composite material. The M source is a raw material capable of providing at least one metal among cerium, magnesium, sodium, potassium, and yttrium, and the weight ratio of Ca / M elements of the Ca source and the M source is 1:0.20 to 0.45. The present invention also includes the material prepared by the above preparation method and its application in carbon dioxide capture and conversion. The material prepared by the preparation method of the present invention has excellent carbon dioxide reduction catalytic activity.

Description

Technical Field

[0001] The present invention belongs to the technical field of industrial process waste gas purification, and specifically relates to the technical field of carbon dioxide catalytic degradation. Background Art

[0002] In view of the problem of carbon dioxide emissions, under the background of "carbon peak and carbon neutrality", the development of efficient CCUS (Carbon Capture, Utilization and Storage) technology is of great significance for realizing the dual-carbon vision of our country. The conventional CCUS whole-process technology covers four links: carbon dioxide capture, transportation, utilization, and storage. However, at present, CCUS projects are facing severe problems such as high energy consumption, high cost, and poor emission reduction effect, and the overall project is in a negative income state. The ICCU (Integrated Carbon Capture and Utilization) technology can omit the processes of enriching, compressing, and transporting CO2 while realizing the high-value utilization of CO2, and has the characteristics of low cost and high efficiency. The key problem for ICCU technology lies in the development of bifunctional materials with the ability to adsorb and in-situ transform CO2. Limited by reaction conditions and adsorption catalytic efficiency, the selection of bifunctional materials has a decisive impact on the technological development in this field. Therefore, optimizing the types and ratios of catalysts and adsorbents and developing economic, efficient, and stable bifunctional materials for use at appropriate temperatures is the future development trend.

[0003] Regarding the research progress of bifunctional materials at home and abroad, the post-capture CO2 utilization technical routes mainly include methanation, reverse water gas shift (to produce carbon monoxide), and dry reforming reactions. Among them, the reverse water gas shift reaction has broad application prospects due to its good product selectivity, high space-time yield of CO, and good cycle stability [1], and can effectively achieve closed carbon chains, reduce storage and transportation costs, and produce high-value syngas. To improve the comprehensive CO yield and cycle stability, many studies have tried to couple solid calcium-based adsorbents with catalytic materials through physical or chemical synthesis methods to achieve in-situ desorption and conversion of CO2 [2-9]. However, due to the low Tamman temperature of calcium-based adsorbents, the particles are prone to sintering and carbon deposition deactivation; in addition, the interaction mechanism between the adsorbent and the catalyst is unclear, and the adsorption, lattice migration, and deoxygenation rates of gaseous CO2 are limited. How to achieve anti-sintering of bifunctional materials and the preparation of a close combination of adsorbent / catalyst is the main problem currently faced by this technology.

[0004] [1] Sun S, Sun H, Williams PT, et al. Recent advances in integrated CO2 capture and utilization: a review [J]. Sustainable Energy & Fuels. 2021, 5: 4546-4559.

[0005] [2] Xu J, Su X, Duan H, et al. Influence of pretreatment temperature on catalytic performance of rutile TiO2-supported ruthenium catalyst in CO2 methanation[J]. Journal of Catalysis. 2016, 333: 227-237.

[0006] [3] Porosoff MD, Yan B, Chen JG. Catalytic reduction of CO2 by H2 for synthesis of CO, methanol and hydrocarbons: challenges and opportunities[J]. Energy & Environmental Science. 2016, 9: 62-73.

[0007] [4] Shao B, Hu G, Alkebsi KAM, et al. Heterojunction-redox catalysts of Fe x Co y [5] Yang L, Pastor-Pérez L, Gu S, et al. Highly efficient Ni / CeO2-Al2O3 catalysts for CO2 upgrading via reverse water-gas shift: Effect of selected transition metal promoters[J]. Applied Catalysis B: Environmental. 2018, 232: 464-471.

[0008] [6] Yang L, Pastor-Pérez L, Gu S, et al. Highly efficient Ni / CeO2-Al2O3 catalysts for CO2 upgrading via reverse water-gas shift: Effect of selected transition metal promoters[J]. Applied Catalysis B: Environmental. 2018, 232: 464-471.

[0009] It should be noted that there seems to be a mistake in the original text where the reference number in is [5] but in the translation it was adjusted to [6] to match the consecutive numbering. If this is not intentional, it should be corrected in the original text.[6]Su X, Yang X, Zhao B, et al. Designing of highly selective and high-temperature endurable RWGS heterogeneous catalysts: recent advances and the future directions[J]. Journal of Energy Chemistry. 2017, 26: 854-867.

[0010] [7]Guo Y, Wang G, Yu J, et al. Tailoring the performance of Ni-CaO dual function materials for integrated CO2 capture and conversion by doping transition metal oxides[J]. Separation and Purification Technology. 2023, 305.

[0011] [8]González- M, Dorneanu B, Arellano-García H. The reverse water gas shift reaction: a process systems engineering perspective[J]. Reaction Chemistry & Engineering. 2021, 6: 954-976.

[0012] [9]Daza Y A, Kuhn J N. CO2 conversion by reverse water gas shift catalysis: comparison of catalysts, mechanisms and their consequences for CO2 conversion to liquid fuels[J]. RSC Advances. 2016, 6: 49675-49691. Summary of the Invention

[0013] Aiming at the problem of unsatisfactory existing carbon dioxide capture and reduction effects, the first object of the present invention is to provide a preparation method of a Ca / M composite material (which can also be called a carbon dioxide capture and reduction catalyst), aiming to prepare a catalyst with both excellent carbon dioxide capture and reduction activities.

[0014] The second object of the present invention is to provide the Ca / M composite material prepared by the above preparation method.

[0015] The third object of the present invention is to provide a method for using the described Ca / M composite material for carbon dioxide capture and reduction, aiming to improve the capture and reduction activity of carbon dioxide.

[0016] A preparation method of a Ca / M composite material, in which a Ca source, an M source, and a complexing agent are pre-reacted and then desolvated to obtain a precursor; the precursor is calcined at a temperature above 500 °C to obtain a precursor material; and then the precursor material is thermally modified in a hydrogen-containing atmosphere to obtain the Ca / M composite material;

[0017] The described M source is a raw material capable of providing at least one metal among cerium, magnesium, sodium, potassium, and yttrium, and the Ca / M element weight ratio of the Ca source to the M source is 1:0.20 - 0.45, and further can be 1:0.25 - 0.35.

[0018] In the present invention, the Ca source and the M source in the described ratio are pre-calcined at the described temperature, and then thermally modified in a hydrogen-containing atmosphere. In this way, the crystal spacing and other physical and chemical structural characteristics of the prepared material can be unexpectedly improved, so as to adapt to the requirements of carbon dioxide capture and reduction catalysis, and improve the carbon dioxide capture and reduction catalytic effect.

[0019] In the present invention, the described Ca source is any component capable of providing Ca materials, for example, optionally at least one of calcium oxides, carbonates, bicarbonates, nitrates, and organic acid salts;

[0020] In the present invention, the described M source is at least one of oxides, carbonates, bicarbonates, nitrates, and organic acid salts of M metal;

[0021] Preferably, the described M is a combination of yttrium and magnesium. Research unexpectedly shows that using the described combined M can unexpectedly further cooperate synergistically with the process, which helps to further jointly control the lattice structure of the product and make it exhibit better carbon dioxide capture and reduction activity.

[0022] In the present invention, when M is a combination of yttrium and magnesium, there is no special requirement for their ratio. For example, the ratio of magnesium to yttrium can be 1:0.1 - 1.

[0023] In the present invention, the described complexing agent includes but is not limited to at least one of citric acid, ethylene glycol, glycine, nitrilotriacetic acid, and ethylenediaminetetraacetic acid;

[0024] Preferably, the weight ratio of the described Ca source to the complexing agent is 1:0.5 - 1, and further can be 1:0.6 - 0.8;

[0025] In the present invention, the solvent in the pre-reaction stage is water, or a mixed solvent of water - organic solvent;

[0026] Preferably, the temperature of the pre-reaction (also known as the gelation reaction) is 50 to 90 °C.

[0027] In the present invention, the way of desolvation (also known as aging) is, for example, evaporation. Among them, the evaporation process can be carried out under normal pressure or negative pressure. The temperature of the desolvation process is, for example, 150 to 200 °C.

[0028] In the present invention, the precursor is innovatively calcined and cooperated with the subsequent thermal modification treatment in a hydrogen-containing atmosphere, so that the phase and crystal lattice spacing of the product can be unexpectedly adjusted, and then it can be adapted to the requirements of carbon dioxide capture and reduction catalysis, and can significantly improve the efficiency and effect of catalytic reduction of carbon dioxide to carbon monoxide.

[0029] In the present invention, the atmosphere in the calcination stage is an oxygen-containing atmosphere, which can be oxygen, or a mixture of oxygen and other gases (such as nitrogen, argon, etc.). Considering the simplicity of the treatment process and cost, it can further be air;

[0030] In the present invention, the calcination temperature is 500 to 750 °C, and further preferably 600 to 700 °C. In the present invention, the regulation of the product phase and crystal lattice spacing can be realized at this lower temperature, and then it can be more adapted to the application requirements of carbon dioxide capture and reduction.

[0031] In the present invention, the holding time at the calcination temperature is 3 to 8 h, and further can be 4 to 5 h.

[0032] Preferably, before calcination, pre-calcination is carried out at a temperature of 250 to 400 °C. In the present invention, the precursor is pre-calcined and then calcined, so that it can further facilitate the regulation of physical and chemical characteristics such as the crystal lattice spacing of the product, make it more adapted to carbon dioxide capture and reduction, and further improve its carbon dioxide reduction effect.

[0033] Preferably, the pre-calcination time is 0.5 to 2 h, and preferably 1 to 1.5 h.

[0034] In the present invention, the content of the gas in the hydrogen-containing atmosphere is 20 to 100 v%, and further can be 30 to 60 v%;

[0035] Preferably, the temperature of the thermal modification stage is 500 to 750 °C, and further preferably 600 to 700 °C;

[0036] Preferably, the holding time at the thermal modification temperature is 1 to 4 h.

[0037] The present invention also provides a Ca / M composite material prepared by the described preparation method.

[0038] The preparation method described in the present invention can endow the material with special phases and characteristics such as crystals and grain boundaries, and the material with such characteristics prepared by the preparation method can unexpectedly meet the requirements of carbon dioxide capture and reduction catalysis, and can significantly improve the yield of carbon monoxide.

[0039] The present invention also provides a method for resource utilization of carbon dioxide-containing waste gas, which uses the Ca / M composite material described in the present invention to capture carbon dioxide in the carbon dioxide-containing waste gas, and then performs reduction treatment in a hydrogen-containing atmosphere to collect the CO product in the reduction stage.

[0040] In the present invention, the carbon dioxide-containing waste gas can be any gas with a demand for carbon dioxide recovery. For example, the carbon dioxide content in the carbon dioxide-containing waste gas is 5-30%, and the nitrogen oxides are <500 mg / m 3 , and the sulfur dioxide is <1000 mg / m 3 , and the particulate matter is <100 mg / m 3 .

[0041] In the present invention, the carbon dioxide capture temperature is 25-750 °C, and considering the treatment efficiency, it can be further 500-700 °C.

[0042] In the present invention, in the reduction stage, the hydrogen content in the hydrogen atmosphere is 30-100 v%, which can be further 40-60 v%, the temperature is 550-750 °C, which can be further 600-700 °C, and more preferably 630-670 °C.

[0043] In the present invention, before capture, the Ca / M composite material is preferably pre-activated with a hydrogen-containing atmosphere, and then capture and subsequent reduction treatment are carried out; in the present invention, before carbon dioxide capture-reduction, it can be preferably pre-activated with a hydrogen-containing atmosphere. Among them, the activation temperature can be optionally 550-750 °C (further can be 600-700 °C), and the time can be optionally 0.1-2 h (further can be 0.5-1 h).

[0044] In the present invention, the Ca / M composite material prepared by the preparation method not only has excellent catalytic reduction activity, but also has excellent structural stability and regeneration ability, and can be used for cyclic capture and reduction treatment to realize cyclic capture and reduction of carbon dioxide.

[0045] Beneficial effects

[0046] In the present invention, the Ca source and M source in the above proportions are pre-calcined at the above temperature, and then thermally modified in a hydrogen-containing atmosphere, so that the crystal spacing and other physical and chemical structural characteristics of the prepared material can be unexpectedly improved, and further the activity of carbon dioxide capture and reduction to carbon monoxide can be improved.

[0047] In the present invention, under the preferred process, the crystal characteristics of the product can be further optimized to better meet the requirements of carbon dioxide capture and reduction applications.

[0048] Research shows that the Ca / M composite material described in the present invention has good stability during the adsorption and calcination cycles, enabling the CO production to reach 13.09 mmol / g. After 29 cycles of experiments, the material maintains a stable production of 7.5 mmol / g. These advantages endow the present invention with superior technical economy. Description of the Drawings

[0049] Figure 1 XRD pattern of the Ca / M composite material prepared in Example 1.

[0050] Figure 2 TEM and elemental scanning images of the Ca / M composite material prepared in Example 1; Detailed Description of the Invention

[0051] An optional method for preparing the Ca / M composite material of the present invention includes the following steps:

[0052] First, a Ca source, an M source, and a chelating agent (citric acid) are dissolved in deionized water to form a mixed solution containing metal ions. Among them, the weight ratio of Ca to M elements in the Ca source and M source is 1:0.20 - 0.45;

[0053] Second, heat the solution in a water bath at 60 - 90 °C with continuous stirring, and then carry out desolvation at 160 - 200 °C for 2 - 10 h to obtain a precursor;

[0054] Third, calcine the precursor in a muffle furnace under an air atmosphere at 500 - 750 °C, more preferably at 600 - 700 °C, to obtain a precursor material.

[0055] Fourth, thermally modify the precursor material in a hydrogen-containing atmosphere to obtain the Ca / M composite material.

[0056] <Integrated CO2 Capture and Utilization Method>

[0057] Another object of the present invention is to provide a method for integrating CO2 capture and utilization using the novel Ca / M composite material of the present invention. The method is characterized in that the novel Ca / M composite material of the present invention is contacted with industrial flue gas at a temperature of 400 - 800 °C to capture carbon dioxide therein, and then catalytically reduced in a hydrogen-containing atmosphere at a temperature of 400 - 800 °C to prepare CO. A further preferred application method of the present invention is to pre-activate the Ca / M composite material in a hydrogen-containing atmosphere, then mix it with a carbon dioxide-containing atmosphere for capture, and then reduce it in a hydrogen-containing atmosphere.

[0058] In the present invention, the above-mentioned carbon dioxide capture and reduction processes can be repeated.

[0059] In the present invention, at the laboratory stage, a composite gas of carbon dioxide and Ar is used as the test simulation gas.

[0060] Example

[0061] The present invention will be further described below with reference to examples. The examples are only used to explain the present invention and are not intended to limit the scope of the present invention. It should be understood that the present invention is not limited to the specific embodiments described below, and those skilled in the art can make various modifications or alterations within the scope of the claims.

[0062] Example 1

[0063] Step a. Preparation of a novel Ca / Mg composite material

[0064] a-1: Calcium carbonate (Ca source), magnesium nitrate (M source), and citric acid (the weight ratio of calcium nitrate to citric acid is 50:30, and the weight ratio of Ca / Mg elements is 1:0.25) are mixed in deionized water, reacted at 60 - 70 °C for 3 - 4 h by water bath heating, and then desolvated at 160 - 170 °C to obtain a precursor. The precursor is then calcined in an air atmosphere at 600 °C for 5 h to obtain a precursor catalyst.

[0065] a-2: The precursor catalyst is placed in a H2-Ar mixed atmosphere (hydrogen content is 50 v%) and heat-modified at 650 °C for 2 h to obtain a Ca / M composite material. XRD is shown in Figure 1 .. TEM and elemental scanning diagrams are shown in Figure 2 , showing that the crystal spacings of Mg and Ca in the material are short, achieving atomic-level composite strengthening.

[0066] Step b. Detection of CO2 capture and conversion performance

[0067] A serial fixed-bed experimental bench is used to detect the effect of the synthesized Ca / M composite material in capturing and utilizing carbon dioxide. The quartz tube used in the fixed bed is 400 mm long and 10 mm in inner diameter, and the temperature range is controlled at 400 - 800 °C. Before the experiment, 0.06 - 0.08 g of quartz wool is placed in the quartz tube, and then 0.3 g of the Ca / M composite material is loaded. The experimental gas conditions are 10% CO2 / Ar, 40% H2 / Ar, and pure Ar for purging. The gas feed components are controlled by a mass flowmeter, and the total flow rate is controlled at 100 ml / min. The gas is mixed and then enters the fixed bed through a pipeline for the experiment.

[0068] First, the CO2 / Ar is introduced for 15 min (the temperature during the treatment stage is T, and the trapping time is maintained at temperature T). After the adsorption ends, Ar is introduced again for purging. Finally, the H2 / Ar is introduced to conduct the carbon dioxide reduction conversion experiment. The time for introducing H2 / Ar is set to 30 min (the temperature during the treatment stage is T, and the reduction conversion time is maintained at temperature T). For the cyclic experiment, the gas switching in the purging, adsorption, and reaction processes is repeated. During the experiment, the components and concentrations of the consumed and generated gases are measured by a non-dispersive infrared analyzer. The instrument measurement error is linearly calibrated with standard gases of different concentrations, and the error is less than ±3% of the total range. The measured active temperature range is 550 - 700 °C. Among them, when the temperature T is 650 °C, the total CO production is 13.1 mmol / g, and the production after 5 cycles at 650 °C is 11.0 mmol / g. When the temperature T is 550 °C, the total CO production is 10.2 mmol / g, and when the temperature T is 700 °C, the total CO production is 11.1 mmol / g.

[0069] Example 2

[0070] Compared with Example 1, the difference is only that the type of M source is changed. The ratio of M to Ca in the M source is the same as that in Example 1. The experimental groups are as follows:

[0071] Group A: The M source is yttrium nitrate;

[0072] Group B: The M source is magnesium nitrate + yttrium nitrate, where the mass ratio of magnesium / yttrium elements is 1:0.2;

[0073] Test is conducted according to the method described in Example 1, and the results are as follows:

[0074] Group A: The active temperature range is 580 - 680 °C. Among them, when the temperature is 650 °C, the total CO production is 8.8 mmol / g.

[0075] Group B: The active temperature range is 560 - 690 °C. Among them, when the temperature is 650 °C, the total CO production is 13.7 mmol / g.

[0076] It can be seen from the comparison between Example 1 and Examples 2A and 2B that by using the combination of M and Ca and matching with the described preparation process, excellent carbon dioxide capture and conversion capabilities can be obtained. Especially when using the combination of Mg and Y as the M source, a better synergistic effect can be unexpectedly obtained.

[0077] Example 3

[0078] Compared with Example 1, the difference is only that the dosage of the Ca source remains unchanged, and the ratio of the weight of Ca / M element is changed to 1:0.33. Other operations and parameters are the same as those in Example 1:

[0079] The test was carried out according to the method described in Example 1, and the results were as follows: when the temperature was 650 °C, the total CO production was 13.0 mmol / g.

[0080] Example 4

[0081] Compared with Example 1, the difference was only that the calcination temperature in step a was changed to 700 °C for 4 h, and the hydrogen content in the atmosphere of thermal modification was 60 v%, the temperature of thermal modification was 700 °C, and the time was 3 h. Other operations and parameters were the same as those in Example 1.

[0082] The test found that when the temperature was 650 °C, the total CO production was 12.9 mmol / g.

[0083] Example 5

[0084] Compared with Example 1, the difference was only that during the calcination process in step a-1, the precursor was first heated to 300 °C and kept warm for 1 h, and then heated to 600 °C and kept warm for 4 h to obtain the precursor catalyst. Other operations and parameters were the same as those in Example 1.

[0085] The test found that when the temperature was 650 °C, the total CO production was 13.6 mmol / g.

[0086] It can be seen from Examples 1 and 5 that by adopting the two-stage gradient process of the present invention, the microscopic physical and chemical structure and crystal spacing of the material can be further improved to make it more suitable for carbon dioxide capture and reduction requirements, and its reduction effect can be further improved.

[0087] Example 6

[0088] Compared with Example 1, the difference was only that in step (b), before introducing the CO2 / Ar capture, a 40 v% hydrogen-Ar atmosphere was introduced into the system and heat-activated at 600 °C for 30 min, and then subsequent treatment was carried out. Other operations and parameters were the same as those in Example 1.

[0089] The test was carried out according to the method described in Example 1, and the results were as follows: when the temperature was 650 °C, the total CO production was 13.8 mmol / g.

[0090] Comparative Example 1

[0091] Compared with Example 1, the difference was only that the calcium source was missing, and the missing share was supplemented equally by the M source. Other operations and parameters were the same as those in Example 1.

[0092] The test was carried out according to the method of Example 1, and the results were that when the temperature was 650 °C, the total CO production was 0.3 mmol / g.

[0093] Comparative Example 2

[0094] Compared with Example 1, the only difference is that the M source is missing, and the missing portion is supplemented equally by the calcium source. Other operations and parameters are the same as in Example 1.

[0095] Tested according to the method of Example 1, the result is that the total CO output at 650 °C is 4.7 mmol / g.

[0096] Comparative Example 3:

[0097] Compared with Example 1, the only difference is that the amount of calcium source is kept unchanged, and the ratio of M / Ca is not adjusted within the required range. The experimental groups are, for example:

[0098] Group A: The elemental ratio of Ca / M is 1:0.14;

[0099] Group B: The ratio of Ca / M is 1:0.65;

[0100] Tested according to the method described in Example 1, the results are as follows:

[0101] Group A: The total CO output at 650 °C is 6.1 mmol / g.

[0102] Group B: The total CO output at 650 °C is 7.9 mmol / g.

[0103] Comparative Example 4

[0104] Compared with Example 1, the only difference is that the calcination temperature is 400 °C, and other operations and parameters are the same as in Example 1.

[0105] Tested according to the method of Example 1, the result is that the total CO output at 650 °C is 6.6 mmol / g.

[0106] Comparative Example 5

[0107] Compared with Example 1, the only difference is that citric acid is missing, and other operations and parameters are the same as in Example 1.

[0108] Tested according to the method of Example 1, the result is that the total CO output at 650 °C is 5.9 mmol / g.

[0109] Comparative Example 6

[0110] The products of Comparative Example 1 and Comparative Example 2 were ball-milled and mixed. Among them, the mass ratio of Mg / Ca is the same as in Example 1. Tested according to the method of Example 1, the result is that the total CO output at 650 °C is 1.1 mmol / g.

[0111] Comparative Example 7

[0112] Compared with Example 1, the only difference is that the reduction treatment step is missing. That is, the hot modification gas is changed from hydrogen to air, and the time is also 2 h;

[0113] Tested according to the method described in Example 1, the results are as follows: the total CO production at a temperature of 650 °C is 6.3 mmol / g.

Claims

1. A preparation method of a Ca / M composite material, characterized in that, The Ca source, M source and complexing agent are pre-reacted and then desolvated to obtain a precursor; the precursor is calcined at a temperature of 600-700 °C for 3-8 h to obtain a precursor material; and then the precursor material is thermally modified in a hydrogen-containing atmosphere to obtain the Ca / M composite material. The temperature in the thermal modification stage is 600-700 °C; the complexing agent includes at least one of citric acid, ethylene glycol, glycine, nitrilotriacetic acid, and ethylenediaminetetraacetic acid; the weight ratio of the Ca source to the complexing agent is 1:0.5-1; the heat preservation time at the thermal modification temperature is 1-4 h. The M source is a raw material capable of providing at least one metal of magnesium and yttrium, and the Ca / M element weight ratio of the Ca source to the M source is 1:0.20-0.

45. The Ca / M composite material is a material capable of capturing carbon dioxide in the waste gas containing carbon dioxide and then obtaining a CO product through reduction treatment in a hydrogen-containing atmosphere.

2. The preparation method of the Ca / M composite material according to claim 1, characterized in that, The Ca source is at least one of calcium oxides, carbonates, bicarbonates, nitrates, and organic acid salts.

3. The preparation method of the Ca / M composite material according to claim 1, characterized in that, The M source is at least one of M metal oxides, carbonates, bicarbonates, nitrates, and organic acid salts.

4. The preparation method of the Ca / M composite material according to claim 1, characterized in that, The M is a combination of yttrium and magnesium.

5. The preparation method of the Ca / M composite material according to claim 1, characterized in that, The weight ratio of the Ca source to the complexing agent is 1:0.6-0.

8.

6. The preparation method of the Ca / M composite material according to claim 1, wherein, The solvent in the pre-reaction stage is water or a mixed solvent of water-organic solvent.

7. The preparation method of the Ca / M composite material according to claim 1, characterized in that, The temperature of the pre-reaction is 50-90 °C.

8. The preparation method of the Ca / M composite material according to claim 1, characterized in that, The atmosphere in the calcination stage is an oxygen-containing atmosphere.

9. The preparation method of the Ca / M composite material according to claim 1, characterized in that, Before calcination, pre-calcination is carried out at a temperature of 250-400 °C.

10. The preparation method of the Ca / M composite material according to claim 9, characterized in that, The time of pre-calcination is 0.5-2 h.

11. The preparation method of the Ca / M composite material according to claim 1, characterized in that, The content of the gas in the hydrogen-containing atmosphere is 20-100 V%.

12. The preparation method of the Ca / M composite material according to claim 1, characterized in that, The heat preservation time at the thermal modification temperature is 2 h or 3 h.

13. A Ca / M composite material prepared by the preparation method according to any one of claims 1-12.

14. A method for resource utilization of carbon dioxide-containing waste gas, characterized in that, Using the Ca / M composite material according to claim 13 to capture carbon dioxide in the waste gas containing carbon dioxide, and then carrying out reduction treatment in a hydrogen-containing atmosphere to collect the CO product in the reduction stage.

15. The method for resource utilization of carbon dioxide-containing waste gas according to claim 14, characterized in that, The carbon dioxide content in the carbon dioxide-containing waste gas is 5-30%, nitrogen oxides <500 mg / m 3 , sulfur dioxide <1000 mg / m 3 , particulate matter <100 mg / m 3 .

16. The resource utilization method of carbon dioxide-containing waste gas according to claim 14, wherein In the reduction stage, the hydrogen content in the hydrogen-containing atmosphere is 30-100 v%, and the temperature is 550-750 °C.

17. The method for resource utilization of carbon dioxide-containing waste gas according to any one of claims 14 to 16, characterized in that, Before capture, the Ca / M composite material is pre-activated with a hydrogen-containing atmosphere, and then capture and subsequent reduction treatment are carried out.

18. The method for resource utilization of carbon dioxide-containing waste gas according to claim 17, characterized in that, The capture and reduction treatment are carried out cyclically.

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