Ba / La-SSZ-13 molecular sieve adsorbent, preparation method thereof and application of Ba / La-SSZ-13 molecular sieve adsorbent in carbon dioxide capture

Abstract

The invention provides a Ba / La-SSZ-13 molecular sieve adsorbent, a preparation method thereof and application of the Ba / La-SSZ-13 molecular sieve adsorbent in carbon dioxide capture, and belongs to the technical field of molecular sieve adsorbents. The Na-SSZ-13 molecular sieve is adopted as a matrix material, barium exchange is firstly carried out, Ba < 2 + > ions are preferentially occupied to the position, closer to the junction of the double chaa cages, in the chaa cages, and the Ba < 2 + > ions can effectively regulate and control the space of the chaa cages, dominate adsorption of carbon dioxide molecules and cooperate with the action of oxygen of a molecular sieve framework on carbon atoms on carbon dioxide, so that adsorption of carbon dioxide is improved. Rare earth metal La < 3 + > ions with extremely strong electrostatic field acting force are selected, through the electrostatic field acting force of a small amount of La < 3 + > on carbon dioxide, the adsorption capacity of the Ba / La-SSZ-13 molecular sieve adsorbent under low partial pressure is enhanced, the situation of difficult desorption cannot be caused, and the obtained Ba / La-SSZ-13 molecular sieve adsorbent has high carbon dioxide adsorption capacity under the condition of low partial pressure.

Description

Technical Field

[0001] This invention relates to the field of molecular sieve adsorbent technology, specifically to a Ba / La-SSZ-13 molecular sieve adsorbent, its preparation method, and its application in carbon dioxide capture. Background Technology

[0002] The increase in atmospheric carbon dioxide concentration has caused serious environmental problems, and solid adsorption methods are widely favored due to their advantages such as high product purity, fast mass transfer rate, simple process, low energy consumption, and environmental friendliness. Among various solid adsorbents, zeolite molecular sieves have advantages such as low cost and high stability, and have been widely used in industrial separation and catalysis. Current research on carbon dioxide adsorption performance based on molecular sieves mainly focuses on several aspects: First, improving adsorption capacity through the addition of template agents or modification with organic amines, for example, patent CN120754815A synthesized a high-efficiency carbon dioxide molecular sieve adsorbent by adding a template agent; patent CN120695770A synthesized a mesoporous molecular sieve using the soft template agent P123, and then improved the adsorption stability of carbon dioxide through Ce doping. Although the assistance of template agents and organic amines can greatly improve the performance of molecular sieve adsorbents, this undoubtedly increases the preparation cost.

[0003] Secondly, molecular sieves can be combined with other materials through doping or compositing to improve the adsorption capacity of carbon dioxide. For example, patent CN107185488A enhances the adsorption capacity of molecular sieves by constructing a porous core-shell structure. CN120695770A discloses that perovskite quantum dots (PQDs) doped with NaY molecular sieve adsorbents can improve the adsorption performance of carbon dioxide, up to 1.346 mmol / g. However, the complexity of the process makes it difficult to apply in practical industrial settings.

[0004] Third, novel molecular sieves are being synthesized. For example, patent CN115417422A discloses a novel FAU molecular sieve synthesized using the seed-gel method, which has a carbon dioxide adsorption capacity of 7.18 mmol / g. The stability of this type of molecular sieve still needs long-term investigation before it can be applied.

[0005] Fourth, the adsorption capacity for carbon dioxide can be enhanced through cation regulation. For example, the BaSrNaLSX molecular sieve disclosed in patent CN113828274A can adsorb 8.4~12.8 wt% carbon dioxide at 10 torr (13.3 mbar); the CaSrNaA molecular sieve disclosed in patent CN113828273A can adsorb 10~13.4 wt% carbon dioxide at 10 torr (13.3 mbar). Their carbon dioxide adsorption capacity under low partial pressure conditions still needs further improvement. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a Ba / La-SSZ-13 molecular sieve adsorbent, its preparation method and its application in carbon dioxide capture. The Ba / La-SSZ-13 molecular sieve adsorbent provided by the present invention has a high carbon dioxide adsorption capacity under low partial pressure conditions.

[0007] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a Ba / La-SSZ-13 molecular sieve adsorbent, which is prepared from raw materials including Ba / La-SSZ-13 molecular sieve powder through molding and calcination; Based on molar ratio, the dry basis chemical composition of the Ba / La-SSZ-13 molecular sieve raw powder is Al2O3·(8~12)SiO2·(0.95~0.98) BaO·(0.02~0.05) La2O3; The metal cations occupying the cation sites of the Ba / La-SSZ-13 molecular sieve include Ba 2+ and La 3+ .

[0008] This invention provides a method for preparing the above-mentioned Ba / La-SSZ-13 molecular sieve adsorbent, comprising the following steps: Na-SSZ-13 molecular sieve raw powder and barium ion-containing aqueous solution were mixed to carry out barium ion exchange reaction to obtain Ba-SSZ-13 molecular sieve. The Ba-SSZ-13 molecular sieve was mixed with an aqueous solution containing lanthanum ions to carry out a lanthanum ion exchange reaction, thereby obtaining Ba / La-SSZ-13 molecular sieve raw powder. The Ba / La-SSZ-13 molecular sieve raw powder, clay, and pore-forming agent are mixed, molded, dried, and calcined to obtain the Ba / La-SSZ-13 molecular sieve adsorbent.

[0009] Preferably, the average pore size of the Na-SSZ-13 molecular sieve raw powder is 3.8 Å; the molar ratio of SiO2 to Al2O3 in the Na-SSZ-13 molecular sieve raw powder is 8~12:1, and the molar ratio of Na2O to Al2O3 is 1:1.

[0010] Preferably, the concentration of barium ions in the barium ion-containing aqueous solution is 0.05~0.3 mol / L; The temperature of the barium ion exchange reaction is 60~90℃, and the time is 1~6h; The degree of barium ion exchange in the barium ion exchange reaction is ≥98%.

[0011] Preferably, the concentration of lanthanum ions in the lanthanum ion-containing aqueous solution is 0.01~0.1 mol / L; The lanthanum ion exchange reaction is carried out at a temperature of 50-80℃ for a time of 0.5-6 hours.

[0012] Preferably, the clay includes one or more of halloysite, kaolin, and attapulgite; The pore-forming agent includes one or more of guar gum powder, starch, and sodium cellulose.

[0013] Preferably, the mass ratio of the Na-SSZ-13 molecular sieve raw powder, clay and pore-forming agent is 16~20:2~3:0~1.

[0014] Preferably, the particle size of the particles obtained after molding is 1.2~1.6mm.

[0015] Preferably, the calcination temperature is 250~500℃, the holding time is 2~6h, and the heating rate to the calcination temperature is 2~10℃ / min.

[0016] This invention provides the application of the above-mentioned Ba / La-SSZ-13 molecular sieve adsorbent in carbon dioxide capture.

[0017] This invention provides a Ba / La-SSZ-13 molecular sieve adsorbent, prepared from raw materials including Ba / La-SSZ-13 molecular sieve powder through molding and calcination; the dry basis chemical composition of the Ba / La-SSZ-13 molecular sieve powder is Al2O3·(8~12)SiO2·(0.95~0.98)BaO·(0.02~0.05)La2O3, based on a molar ratio; the metal cations occupying the cation sites of the Ba / La-SSZ-13 molecular sieve include Ba... 2+ and La 3+ This invention uses Na-SSZ-13 molecular sieve as the matrix material. Na-SSZ-13 molecular sieve has a CHA topology, with the cha cage being the core of the CHA molecular sieve framework. It is a complex and symmetrical polyhedron, its cage walls composed of eight six-membered rings and six eight-membered rings. The eight-membered rings are the main channels of the cha cage, with a pore size of approximately 3.8 Å. The Ba... 2+ The ions are located closer to the boundary between the two cages within the cha cage, while La 3+ The ions are mainly located in the cha cage near the eight-membered ring channels. La, possessing a trivalent charge... 3+ The extremely strong electrostatic field generated by the ions enhances the adsorption strength of carbon dioxide, especially at low partial pressures. Typically, large amounts of La... 3+ Ions are difficult to desorb due to their strong adsorption properties, but the La controlled by this invention... 3+ With limited ion loading, La primarily serves to guide guest molecules.3+ The ions, located near the eight-membered ring channel within the cha cage, attract carbon dioxide into the cha cage. 2+ The occupancy of ions not only effectively modulates the spatial size but also exhibits a strong carbon dioxide adsorption capacity. In summary, La... 3+ The electrostatic field effect of ions and Ba 2+ The excellent occupancy of ions drives the significant enhancement of the adsorption capacity for guest molecules such as carbon dioxide, especially under low partial pressure conditions, resulting in a high carbon dioxide adsorption capacity for the molecular sieve. The results of the examples show that the Ba / La-SSZ-13 molecular sieve provided by this invention exhibits extremely high static adsorption capacity for carbon dioxide at 1 mbar, 10 mbar, and 1 bar, reaching a maximum of 10.9 wt% at 1 mbar, 17.4 wt% at 10 mbar, and 25.3 wt% at 1 bar, with an adsorption heat as low as 56.2 kJ / mol, ensuring effective regeneration.

[0018] This invention provides a method for preparing the above-mentioned Ba / La-SSZ-13 molecular sieve adsorbent. This invention first involves barium exchange, causing Ba... 2+ Ions preferentially occupy positions closer to the bicage boundary within the cha cage, Ba 2+ Ions effectively regulate the space of the cha cage, dominating the adsorption of carbon dioxide molecules, and synergistically enhance the adsorption of carbon dioxide by the interaction of oxygen in the molecular sieve framework with carbon atoms on the carbon dioxide. This invention selects the rare earth metal La, which possesses extremely strong electrostatic field forces. 3+ The addition of small amounts of ions, positioned appropriately, enhances the adsorption capacity of carbon dioxide at low partial pressures through electrostatic forces, without causing desorption difficulties. Furthermore, the preparation method provided by this invention utilizes readily available and inexpensive raw materials, resulting in low production costs, simple operation, and suitability for industrial production. Attached Figure Description

[0019] Figure 1 The image shows a SEM image of the Ba / La-SSZ-13 molecular sieve adsorbent obtained in Example 1. Figure 2 The image shows the static adsorption isotherm of carbon dioxide for the Ba / La-SSZ-13 molecular sieve adsorbent in Example 2. Detailed Implementation

[0020] This invention provides a Ba / La-SSZ-13 molecular sieve adsorbent, which is prepared from raw materials including Ba / La-SSZ-13 molecular sieve powder through molding and calcination.

[0021] In this invention, the dry basis chemical composition of the Ba / La-SSZ-13 molecular sieve raw powder, based on molar ratio, is Al2O3·(8~12)SiO2·(0.95~0.98)BaO·(0.02~0.05)La2O3, preferably Al2O3·(9~11)SiO2·(0.96~0.97)BaO·(0.03~0.04)La2O3, and more preferably Al2O3·10SiO2·0.97BaO·0.03La2O3, wherein the molar amount of Al2O3 is 1.

[0022] In this invention, the metal cation occupying the cation sites of the Ba / La-SSZ-13 molecular sieve includes Ba. 2+ and La 3+ This invention uses Na-SSZ-13 molecular sieve as a matrix. Na-SSZ-13 molecular sieve has a CHA topology, which features eight-membered ring channels with a pore size of approximately 3.8 Å. This ensures good accommodation of carbon dioxide molecules (3.3 Å) while maintaining ion-modified space, providing a novel adsorbent material for low-concentration carbon dioxide adsorption. This invention first involves barium exchange, allowing Ba... 2+ Ions preferentially occupy positions closer to the bicage boundary within the cha cage, Ba 2+ Ions effectively regulate the space of the cha cage, dominating the adsorption of carbon dioxide molecules, and synergistically enhance the adsorption of carbon dioxide by the interaction of oxygen in the molecular sieve framework with carbon atoms on the carbon dioxide. This invention selects the rare earth metal La, which possesses extremely strong electrostatic field forces. 3+ The addition of small amounts of ions, which are placed in suitable positions, can enhance the adsorption capacity of carbon dioxide at low partial pressures through the electrostatic field force on it, without causing desorption difficulties.

[0023] This invention provides a method for preparing the above-mentioned Ba / La-SSZ-13 molecular sieve adsorbent, comprising the following steps: Na-SSZ-13 molecular sieve raw powder and barium ion-containing aqueous solution were mixed to carry out barium ion exchange reaction to obtain Ba-SSZ-13 molecular sieve. The Ba-SSZ-13 molecular sieve was mixed with an aqueous solution containing lanthanum ions to carry out a lanthanum ion exchange reaction, thereby obtaining Ba / La-SSZ-13 molecular sieve raw powder. The Ba / La-SSZ-13 molecular sieve raw powder, clay, and pore-forming agent are mixed, molded, dried, and calcined to obtain the Ba / La-SSZ-13 molecular sieve adsorbent.

[0024] In this invention, the Na-SSZ-13 molecular sieve raw powder is preferably an all-sodium SSZ-13 molecular sieve. In this invention, the average pore size of the Na-SSZ-13 molecular sieve raw powder is preferably 3.8 Å; the molar ratio of SiO2 to Al2O3 in the Na-SSZ-13 molecular sieve raw powder is preferably 8~12:1, more preferably 9~11:1, and even more preferably 10:1; the molar ratio of Na2O to Al2O3 is preferably 1:1.

[0025] In this invention, the source of the Na-SSZ-13 molecular sieve powder is preferably commercially available, and the purchasing company is preferably Luoyang Jianlong Micro-Nano New Materials Co., Ltd.

[0026] This invention involves mixing Na-SSZ-13 molecular sieve powder with a barium ion-containing aqueous solution to perform a barium ion exchange reaction, thereby obtaining Ba-SSZ-13 molecular sieve. In this invention, the barium source in the barium ion-containing aqueous solution is preferably one or more of barium nitrate, barium chloride, and barium sulfate; the concentration of barium ions in the barium ion-containing aqueous solution is preferably 0.05~0.3 mol / L, more preferably 0.1~0.25 mol / L, and even more preferably 0.15~0.2 mol / L. In this invention, the volume ratio of the dry weight of the Na-SSZ-13 molecular sieve powder to the barium ion-containing aqueous solution is preferably 1g:2~5mL, more preferably 1g:3~4mL.

[0027] In this invention, the temperature of the barium ion exchange reaction is preferably 60-90°C, more preferably 70-80°C, and the time is preferably 1-6 hours, more preferably 2-5 hours, and even more preferably 3-4 hours. In this invention, the degree of barium ion exchange in the barium ion exchange reaction is preferably ≥98%, and this invention preferably repeats the barium ion exchange reaction to ensure the degree of barium ion exchange meets the requirement. After the barium ion exchange reaction, this invention preferably performs water washing and drying.

[0028] This invention involves mixing the Ba-SSZ-13 molecular sieve with an aqueous solution containing lanthanum ions to perform a lanthanum ion exchange reaction, yielding Ba / La-SSZ-13 molecular sieve raw powder. In this invention, the lanthanum source in the aqueous solution containing lanthanum ions is preferably one or more of lanthanum nitrate, lanthanum chloride, and lanthanum sulfate. In this invention, the concentration of lanthanum ions in the aqueous solution containing lanthanum ions is preferably 0.01~0.1 mol / L, more preferably 0.02~0.08 mol / L, and even more preferably 0.04~0.05 mol / L. In this invention, the volume ratio of the dry weight of the Ba-SSZ-13 molecular sieve raw powder to the aqueous solution containing lanthanum ions is preferably 1g:2~5mL, more preferably 1g:3~4mL.

[0029] In this invention, the temperature of the lanthanum ion exchange reaction is preferably 50-80°C, more preferably 60-70°C, and the time is preferably 0.5-6 hours, more preferably 1-5 hours, and even more preferably 2-4 hours. After the lanthanum ion exchange reaction, the present invention preferably performs washing with water and drying.

[0030] This invention involves mixing the Ba / La-SSZ-13 molecular sieve powder, clay, and a pore-forming agent, followed by molding, drying, and calcination to obtain a Ba / La-SSZ-13 molecular sieve adsorbent. In this invention, the clay preferably comprises one or more of halloysite, kaolin, and attapulgite, more preferably halloysite, which preferably has a nanotube-like hollow structure. In this invention, the particle size of the clay is preferably 200-400 mesh, more preferably 300 mesh. In this invention, the pore-forming agent preferably comprises one or more of guar gum powder, starch, and sodium cellulose.

[0031] In this invention, the preferred mass ratio of Na-SSZ-13 molecular sieve powder, clay, and pore-forming agent is 16~20:2~3:0~1, more preferably 17~19:2.2~2.8:0.2~0.5, further preferably 17~19:2.3~2.7:0.25~0.45, and most preferably 17.5~18:2.4~2.6:0.3~0.4.

[0032] In this invention, the molding is preferably carried out in a pelletizing device. This invention does not impose any particular limitation on the pelletizing device; any pelletizing device well-known to those skilled in the art can be used. In this invention, the particle size of the Ba / La-SSZ-13 pellets is preferably 1.2~1.7 mm, more preferably 1.3~1.6 mm.

[0033] In this invention, the drying temperature is preferably 60~100℃, more preferably 70~900℃; the drying time is preferably 2~8h, more preferably 3~7h.

[0034] The roasting temperature is preferably 250~500℃, more preferably 300~450℃; the heating rate from room temperature to the roasting temperature is preferably 2~10℃ / min, more preferably 3~8℃ / min; the roasting time is preferably 2~6h, more preferably 3~5h, starting from the time the temperature reaches the roasting temperature; the roasting atmosphere is preferably air.

[0035] This invention provides the application of the above-mentioned Ba / La-SSZ-13 molecular sieve adsorbent in the adsorption of carbon dioxide. In this invention, the pressure of the carbon dioxide-containing gas is preferably 1 mbar to 1 bar during the application.

[0036] The following detailed description, in conjunction with embodiments, illustrates the Ba / La-SSZ-13 molecular sieve adsorbent provided by this invention, its preparation method, and its application in carbon dioxide capture. However, these descriptions should not be construed as limiting the scope of protection of this invention.

[0037] Example 1 (1) Place 100 g (dry weight) of Na-SSZ-13 molecular sieve raw powder (Al2O3·10SiO2·Na2O) in 300 mL of barium nitrate solution with a barium ion concentration of 0.2 mol / L, heat to 80 °C and keep warm for 3 h, repeat the above barium ion exchange reaction until the molar amount of barium ions is more than 98% of the total molar amount of metal cations at the cation sites (as measured by X-ray fluorescence spectrometry (XRF)), and filter. Wash the obtained solid product with water to obtain Ba-SSZ-13 molecular sieve raw powder.

[0038] (2) The Ba-SSZ-13 molecular sieve raw powder was placed in 300 mL of lanthanum nitrate solution with a lanthanum ion concentration of 0.1 mol / L, heated to 60°C and kept warm for 1 h, filtered, and the obtained solid product was washed with water to obtain Ba / La-SSZ-13 molecular sieve raw powder.

[0039] (3) Ba / La-SSZ-13 molecular sieve raw powder, halloysite and guar gum powder are mixed in a mass ratio of 18:2.5:0.3 to obtain mixed powder; the mixed powder is added to a pelletizing device to form pellets to obtain Ba / La-SSZ-13 pellets with a diameter of 1.2~1.6mm; (4) The Ba / La-SSZ-13 shaped spheres were dried at 80°C for 6 hours and calcined at 400°C for 5 hours to obtain Ba / La-SSZ-13 molecular sieve adsorbent. The dry basis chemical composition of the molecular sieve was Al2O3·10 SiO2·0.97 BaO·0.03 La2O3.

[0040] The SEM image of the Ba / La-SSZ-13 molecular sieve adsorbent obtained in Example 1 is shown below. Figure 1 As stated, by Figure 1 It can be seen that the obtained Ba / La-SSZ-13 sample has a highly regular cubic morphology. All crystals show clear and sharp edges and smooth and flat crystal faces, and have good dispersion. The crystal size is uniform, and the side length is mainly concentrated in 0.2~0.3μm.

[0041] Example 2 (1) Place 100 g (dry weight) of Na-SSZ-13 molecular sieve raw powder (Al2O3·10SiO2·Na2O) in 300 mL of barium nitrate solution with a barium ion concentration of 0.2 mol / L, heat to 80 °C and keep warm for 3 h, repeat the above barium ion exchange reaction until the molar amount of barium ions is more than 98% of the total molar amount of metal cations at the cation sites, and filter. Wash the obtained solid product with water to obtain Ba-SSZ-13 molecular sieve raw powder.

[0042] (2) The Ba-SSZ-13 molecular sieve raw powder was placed in 300 mL of lanthanum nitrate solution with a lanthanum ion concentration of 0.2 mol / L, heated to 60℃ and kept warm for 1 h, filtered, and the obtained solid product was washed with water to obtain Ba / La-SSZ-13 molecular sieve raw powder.

[0043] (3) Ba / La-SSZ-13 molecular sieve raw powder, halloysite and guar gum powder are mixed in a mass ratio of 18:2.5:0.3 to obtain mixed powder; the mixed powder is added to a pelletizing device to form pellets to obtain Ba / La-SSZ-13 pellets with a diameter of 1.2~1.6mm; (4) The Ba / La-SSZ-13 shaped spheres were dried at 80°C for 6 hours and calcined at 400°C for 5 hours to obtain Ba / La-SSZ-13 molecular sieve adsorbent. The dry chemical composition of the molecular sieve was Al2O3·10SiO2·0.95BaO·0.05La2O3.

[0044] Comparative Example 1 (1) Place 100 g (dry weight) of Na-SSZ-13 molecular sieve raw powder (Al2O3·10SiO2·Na2O) in 300 mL of barium nitrate solution with a barium ion concentration of 0.2 mol / L, heat to 80 °C and keep warm for 3 h, repeat the above barium ion exchange reaction until the molar amount of barium ions is more than 98% of the total molar amount of metal cations at the cation sites, and filter. Wash the obtained solid product with water to obtain Ba-SSZ-13 molecular sieve raw powder.

[0045] (2) The Ba-SSZ-13 molecular sieve raw powder was placed in 300 mL of lanthanum nitrate solution with a lanthanum ion concentration of 0.8 mol / L, heated to 60℃ and kept warm for 3 h, filtered, and the obtained solid product was washed with water to obtain Ba / La-SSZ-13 molecular sieve raw powder.

[0046] (3) Ba / La-SSZ-13 molecular sieve raw powder, halloysite and guar gum powder are mixed in a mass ratio of 18:2.5:0.3 to obtain mixed powder; the mixed powder is added to a pelletizing device to form pellets to obtain Ba / La-SSZ-13 pellets with a diameter of 1.2~1.6mm; (4) The Ba / La-SSZ-13 molded spheres were dried at 80°C for 6 hours and calcined at 400°C for 5 hours to obtain Ba / La-SSZ-13 molecular sieve adsorbent. The dry chemical composition of the molecular sieve was Al2O3·10SiO2·0.6BaO·0.4La2O3.

[0047] Comparative Example 2 (1) Place 100 g (dry weight) of Na-SSZ-13 molecular sieve raw powder (Al2O3·10SiO2·Na2O) in 300 mL of barium nitrate solution with a barium ion concentration of 0.2 mol / L, heat to 80 °C and keep warm for 3 h, repeat the above barium ion exchange reaction until the molar amount of barium ions is more than 98% of the total molar amount of metal cations at the cation sites, and filter. Wash the obtained solid product with water to obtain Ba-SSZ-13 molecular sieve raw powder.

[0048] (2) Ba-SSZ-13 molecular sieve raw powder, halloysite and guar gum powder are mixed in a mass ratio of 18:2.5:0.3 to obtain mixed powder; the mixed powder is added to a pelletizing device to form pellets to obtain Ba-SSZ-13 pellets with a diameter of 1.2~1.6mm; (3) The Ba-SSZ-13 type spheres were dried at 80℃ for 6 hours and calcined at 400℃ for 5 hours to obtain Ba-SSZ-13 molecular sieve adsorbent. The dry chemical composition of the molecular sieve is Al2O3·10SiO2·BaO.

[0049] Comparative Example 3 (1) 100 g (dry weight) of Na-SSZ-13 molecular sieve raw powder (Al2O3·10SiO2·Na2O) was placed in 300 mL of barium nitrate solution with a barium ion concentration of 0.2 mol / L, heated to 80 °C and kept at that temperature for 3 h, and then filtered. The obtained solid product was washed with water to obtain Ba / Na-SSZ-13 molecular sieve raw powder.

[0050] (2) Ba-SSZ-13 molecular sieve raw powder, halloysite and guar gum powder are mixed in a mass ratio of 18:2.5:0.3 to obtain mixed powder; the mixed powder is added to a pelletizing device to form pellets to obtain Ba / Na-SSZ-13 pellets with a diameter of 1.2~1.6mm; (3) The Ba / Na-SSZ-13 shaped spheres were dried at 80°C for 6 hours and calcined at 400°C for 5 hours to obtain Ba / Na-SSZ-13 molecular sieve adsorbent. The dry chemical composition of the molecular sieve was Al2O3·10SiO2·0.8BaO·0.2Na2O.

[0051] Comparative Example 4 (1) Na-SSZ-13 molecular sieve raw powder (Al2O3·10SiO2·Na2O), halloysite and guar gum powder are mixed in a mass ratio of 18:2.5:0.3 to obtain mixed powder; the mixed powder is added to a pelletizing device to form pellets to obtain Na-SSZ-13 pellets with a size of 1.2~1.6mm; (2) The Na-SSZ-13 shaped spheres were dried at 80°C for 6 hours and calcined at 400°C for 5 hours to obtain Na-SSZ-13 molecular sieve adsorbent. The dry chemical composition of the molecular sieve was Al2O3·10SiO2·Na2O.

[0052] Test case Carbon dioxide adsorption capacity and heat of adsorption of the molecular sieves prepared in Examples 1-2 and Comparative Examples 1-4.

[0053] Test methods: Static adsorption method, degassing at 300℃ for 2-5 hours; static adsorption capacity of carbon dioxide was determined at 298K and 100kPa. Heat of adsorption, purging at 300℃ for 3 hours; heat of adsorption of carbon dioxide was determined by simultaneous thermal analyzer at 298K and 100kPa.

[0054] The static adsorption capacity and adsorption heat of carbon dioxide of the molecular sieves prepared in Examples 1-2 and Comparative Examples 1-4 are shown in Table 1.

[0055] Table 1. Carbon dioxide adsorption performance of molecular sieves prepared in Examples 1-2 and Comparative Examples 1-4

[0056] As shown in Table 1, the Ba / La-SSZ-13 molecular sieves prepared in Examples 1 and 2 all exhibited extremely high static carbon dioxide adsorption capacity under conditions of 1 mbar, 10 mbar and 1 bar, with a maximum of 10.9 wt% at 1 mbar, 17.4 wt% at 10 mbar and 25.3 wt% at 1 bar, and an adsorption heat as low as 56.2 kJ / mol, which can ensure regeneration effect.

[0057] The static adsorption isotherm of carbon dioxide for the Ba / La-SSZ-13 molecular sieve adsorbent in Example 2 is shown below. Figure 2 As shown, by Figure 2 It can be seen that the Ba / La-SSZ-13 sample exhibits extremely high carbon dioxide adsorption capacity, especially under extremely low pressure conditions (0~10 mbar). Specifically, it can reach up to about 10 wt% at 1 mbar, which is very suitable for capturing carbon dioxide under low partial pressure conditions.

[0058] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A Ba / La-SSZ-13 molecular sieve adsorbent characterized in that, The Ba / La-SSZ-13 molecular sieve is prepared from raw materials including Ba / La-SSZ-13 molecular sieve powder through shaping and calcination; The dry base chemical composition of the Ba / La-SSZ-13 molecular sieve powder is Al2O3·(8-12)SiO2·(0.95-0.98)BaO·(0.02-0.05)La2O3 in terms of molar ratio; Metal cations occupying the cation sites of the Ba / La-SSZ-13 molecular sieve include Ba 2+ and La 3+ .

2. The method of making the Ba / La-SSZ-13 molecular sieve adsorbent of claim 1, characterized by, The method comprises the following steps: The Na-SSZ-13 molecular sieve powder is mixed with a barium ion-containing aqueous solution to perform a barium ion exchange reaction, thereby obtaining a Ba-SSZ-13 molecular sieve; The Ba-SSZ-13 molecular sieve is mixed with a lanthanum ion-containing aqueous solution to perform a lanthanum ion exchange reaction, thereby obtaining the Ba / La-SSZ-13 molecular sieve powder; The Ba / La-SSZ-13 molecular sieve powder, clay and pore-forming agent are mixed to perform shaping, drying and calcination, thereby obtaining a Ba / La-SSZ-13 molecular sieve adsorbent.

3. The production method according to claim 2, characterized by, The average pore size of the Na-SSZ-13 molecular sieve powder is 3.8 Å; the molar ratio of SiO2 to Al2O3 of the Na-SSZ-13 molecular sieve powder is 8-12:1, and the molar ratio of Na2O to Al2O3 is 1:

1.

4. The production method according to claim 2, characterized by, The concentration of barium ions in the barium ion-containing aqueous solution is 0.05-0.3 mol / L; The temperature of the barium ion exchange reaction is 60-90℃, and the time is 1-6 h; The barium ion exchange degree of the barium ion exchange reaction is ≥98%.

5. The preparation method according to claim 2, characterized in that, The concentration of lanthanum ions in the lanthanum ion-containing aqueous solution is 0.01-0.1 mol / L; The temperature of the lanthanum ion exchange reaction is 50-80℃, and the time is 0.5-6 h.

6. The preparation method according to claim 2, characterized in that, The clay comprises one or more of halloysite, kaolin and attapulgite; The pore-forming agent comprises one or more of sesbania powder, starch and sodium cellulose.

7. The production method according to claim 2 or 6, characterized by, The mass ratio of the Na-SSZ-13 molecular sieve, clay and pore-forming agent is 16-20:2-3:0-1.

8. The preparation method according to claim 2, characterized in that, The particle size of the obtained granules after shaping is 1.2-1.6 mm.

9. The preparation method according to claim 2, characterized in that, The temperature of the calcination is 250-500℃, the holding time is 2-6 h, and the heating rate for heating to the calcination temperature is 2-10℃ / min.

10. The application of the Ba / La-SSZ-13 molecular sieve adsorbent of claim 1 or the Ba / La-SSZ-13 molecular sieve adsorbent prepared by the preparation method of any one of claims 2-9 in carbon dioxide capture.

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