Low energy carbon capture absorbent based on polyetheramine-alcohol-water system and its catalytic regeneration method

Abstract

The present application relates to low energy consumption carbon capture absorbent based on polyether amine-alcohol-water system and its catalytic regeneration method, belong to carbon capture technical field.The absorbent is composed of polyether amine, organic alcohol and deionized water, wherein the polyether amine is preferably D230, and the organic alcohol is preferably C3-C4 monohydric alcohol;The absorbent has the characteristics of low viscosity, high absorption capacity and good cycle stability;The present application also discloses a kind of for the catalytic regeneration of the absorbent monolithic catalyst, which uses foamed nickel as carrier, and has NiS2 active layer in situ growth on the surface.Catalytic regeneration method includes: the rich liquid after absorbing CO2 saturation is heated to 95-105 DEG C, and the catalytic desorption is carried out by adding the monolithic catalyst.The absorbent and catalytic regeneration method provided by the present application can significantly reduce the CO2 desorption temperature, improve the desorption rate, reduce the regeneration energy consumption, and have good industrial application prospect.

Description

Technical Field

[0001] This invention belongs to the field of carbon capture technology, specifically relating to a low-energy carbon capture absorbent based on a polyetheramine-alcohol-water system and its catalytic regeneration method. Technical Background

[0002] To mitigate atmospheric CO2 concentrations, carbon capture, utilization, and storage (CCUS) technology is currently one of the most effective methods, and organic amine absorption, as a highly efficient and mature carbon capture technology, has been widely applied. For example, ethanolamine (MEA) is a commonly used absorbent in chemical absorption, but its high energy consumption during desorption has become a key factor restricting its large-scale industrial application. Therefore, developing more energy-efficient absorbents has become a research hotspot.

[0003] Currently, alkanolamine solvents are well-established in CO2 capture. Diamines, due to their two amino groups, can react with CO2 to form more stable cyclic carbonates, typically exhibiting higher absorption capacity and rate. Polyetheramines, as a typical diamine, contain abundant ether bonds and amino groups in their molecular structure, possessing good chemical stability, heat resistance, and corrosion resistance, along with relatively low viscosity and volatility, theoretically possessing the potential to reduce equipment corrosion and solvent loss. However, no research has yet systematically explored the application potential of polyetheramines in CO2 capture, especially how to address the potential problems of drastic viscosity increases and mass transfer deterioration during CO2 absorption.

[0004] In simple organic amine systems, the absorption agent increases the viscosity of the system during CO2 capture, which is detrimental to further absorption and desorption. However, the advantages of the absorbent become more apparent after adding deionized water to the organic amine system. It not only reduces the viscosity and enhances gas-liquid mass transfer, thus increasing the CO2 absorption rate, but also consumes less energy and has a higher desorption rate compared to ethanolamine solutions, while requiring a lower temperature. Therefore, this absorbent combines properties such as viscosity, absorption rate, and desorption rate.

[0005] However, traditional methods require heating the solution to 110-130 degrees Celsius. o C, this process requires a large amount of thermal energy. While maintaining the existing absorbent system and process flow, catalytic desorption is an effective strategy to further reduce regeneration energy consumption. The use of catalysts can significantly reduce regeneration energy consumption, thereby significantly reducing the operating costs of the carbon capture system.

[0006] In summary, there is an urgent need to develop a novel amine-based absorbent with low viscosity, high absorption capacity, low regeneration energy consumption, and recyclability, along with a highly efficient catalytic regeneration technology, to address the core pain points of traditional carbon capture technologies, such as high energy consumption, high viscosity, and high corrosion, and to promote the industrial application of CCUS technology. Summary of the Invention

[0007] The purpose of this invention is to provide a low-energy carbon capture absorbent based on a polyetheramine-alcohol-water system and its catalytic regeneration method, aiming to solve the technical problems of high regeneration energy consumption, excessive viscosity of the absorption process system, and easy corrosion of equipment in existing organic amine carbon capture technologies, thereby achieving low-energy carbon capture with low viscosity, high absorption capacity, low desorption temperature, rapid catalytic regeneration, and long-term stable cycle.

[0008] On the one hand, the present invention provides a low-energy carbon capture and absorbent based on a polyetheramine-alcohol-water system, employing the following technical solution: A low-energy carbon capture and absorbent system of polyetheramine-alcohol-water, wherein the low-energy carbon capture and absorbent comprises polyetheramine, organic alcohol and deionized water; The molar ratio of the polyetheramine, organic alcohol and deionized water is 1:(0.1~10):(0.1~10).

[0009] Preferably, the polyetheramine is polyetheramine D230.

[0010] Preferably, the organic alcohol is a C3-C4 monohydric alcohol; The difference between the boiling point of the organic alcohol and the boiling point of water does not exceed 20°C.

[0011] Preferably, the organic alcohol is n-propanol, isopropanol, n-butanol, or isobutanol.

[0012] On the one hand, the present invention provides a catalytic regeneration method for the above-mentioned low-energy carbon capture and absorbent, employing the following technical solution: A catalytic regeneration method for low-energy carbon capture and absorbent includes the following steps: Heat the CO2-saturated solution to the desorption temperature; and / or An integral catalyst is added to the rich solution to catalyze the desorption of CO2.

[0013] Preferably, the monolithic catalyst uses nickel foam as a carrier, and a NiS2 active layer is grown in situ on the surface of the nickel foam; the NiS2 active layer has a nanosheet-like, nanowire-like, or nanoflower-like microstructure.

[0014] Preferably, the desorption temperature is 95~105℃.

[0015] Preferably, the desorption time is 0.5 to 2 hours.

[0016] Preferably, the preparation method of the monolithic catalyst is as follows: 1) Pretreatment of nickel foam; 2) Ni-LDH / NF precursors were synthesized on the surface of pretreated nickel foam using a hydrothermal or solvothermal method; 3) The Ni-LDH / NF precursor is mixed with a sulfur source and subjected to sulfidation heat treatment to obtain a NiS2 / NF monolithic catalyst.

[0017] Preferably, in step 2), the hydrothermal or solvothermal reaction temperature is 120~200℃, and the reaction time is 6~24h.

[0018] In summary, the present invention has the following beneficial technical effects: 1. This invention, by compounding polyetheramine D230 with organic alcohol and deionized water in a specific ratio, utilizes the dilution effect of water and the solubilizing effect of organic alcohol to effectively inhibit the excessive polymerization of carbamate during CO2 absorption. Experimental data show that, compared with the anhydrous system (viscosity as high as 1783 mPa·s), the viscosity of the absorbent of this invention can be reduced by more than 90% after absorbing CO2, significantly improving gas-liquid mass transfer efficiency and increasing the CO2 absorption rate.

[0019] 2. The low-energy carbon capture and absorbent of this invention exhibits excellent absorption performance for simulated flue gas (15% CO2) under mild conditions of 30-50℃. Example data shows that when the molar ratio of polyetheramine D230, n-propanol, and water is 1:1:4, the absorption capacity reaches 933.4 mL / L (based on CO2 volume), far exceeding that of the system without added water (750.5 mL / L), achieving high-capacity capture.

[0020] 3. The desorption temperature of the low-energy carbon capture absorbent in this invention is up to 105℃, which is 15-25℃ lower than the 110-130℃ of the traditional ethanolamine system. Relative heat load tests show that, compared with 5M MEA solution, the heat load of the absorbent in this invention is reduced by 20%, effectively reducing energy consumption in the carbon capture process.

[0021] 4. The monolithic catalyst in this invention uses nickel foam as a self-supporting carrier, and the in-situ grown NiS2 nanosheet active layer on its surface has abundant catalytic active sites. In the catalytic desorption experiment, at 95℃, the highest desorption rate after adding the catalyst reached 8 mL / s, which is 45.5% higher than the blank control group (95℃) without catalyst, and the desorption time was shortened from 80 minutes to 60 minutes. This indicates that the catalyst can effectively reduce the decomposition activation energy of CO2 bound state (carbamate), achieving rapid desorption at lower temperatures. Attached Figure Description

[0022] Figure 1 This is the preparation process of the monolithic catalyst NiS2 / NF provided in the embodiments of the present invention; Figure 2 In the image, a represents the X-ray diffraction (XRD) pattern of the NiS2 / NF monolithic catalyst. Figure 2 In the middle b, the scanning electron microscope (SEM) images of the NiS2 / NF monolithic catalyst at different magnifications are shown. Figure 3 This is a viscosity comparison chart of the absorbents in Comparative Examples 1-3 of the present invention. Figure 4 In Figure 'a', the CO2 absorption rate of the absorbent in Example 1 changes over time at different absorption temperatures. Figure 4 In Figure b, the CO2 absorption rate of the absorbents in Comparative Examples 1, 4, 8 and 1 changes over time. Figure 5 This is a comparison chart of the viscosity changes and maximum CO2 desorption rates of the absorbents before and after CO2 absorption in Comparative Examples 1, 4, 8 and 1 of the present invention. Figure 6 In Figure a, the absorption rate curves of the absorbents in Comparative Examples 4-7 of this invention are shown. Figure 6 In Figure b, the absorption capacity of the absorbents in Comparative Examples 4-7 of this invention is shown in a bar chart. Figure 6 In the figure, c represents the absorption rate curves of the absorbents in Comparative Examples 4-7, Comparative Example 9, and Examples 1-2 of the present invention. Figure 6 In the figure, d represents a bar chart showing the absorption capacity of the absorbents in Comparative Examples 4, 6, 9, and Examples 1-2 of this invention. Figure 7 In Figure 'a', the curves showing the CO2 desorption rate of the absorbent in Example 1 as a function of time at different desorption temperatures are presented. Figure 7 In Figure b, the viscosity of the absorbent in Example 1 and Comparative Example 4 of this invention changes over time. Figure 8 In Figure a, CO2 desorption rate varies with time during the temperature-programmed desorption process of the absorbents in Comparative Examples 4, 9, and 1-2 of this invention. Figure 8 In Figure b, the CO2 desorption capacity of the absorbents of Comparative Examples 4, 9 and Examples 1-2 of the present invention changes with time during the temperature-programmed desorption process. Figure 9 In Figure a, there is a bar chart comparing the CO2 desorption capacity and regeneration heat load of the absorbents in Examples 1-2 and Comparative Examples 9-10 of this invention. Figure 9 In Figure b, the bar chart shows the change in CO2 absorption capacity of the absorbent in Example 1 of this invention with the number of absorption-desorption cycles. Figure 10 In Figure 'a', the CO2 desorption rate of the absorbent in Example 1 changes over time with or without the NiS2 / NF monolithic catalyst. Figure 10 In Figure b, the CO2 desorption capacity of the absorbent in Example 1 changes over time with or without the NiS2 / NF monolithic catalyst. Detailed Implementation

[0023] The following examples, comparative examples, and appendices are used in conjunction with the embodiments. Figure 1-10 The present invention will be described in further detail below.

[0024] Preparation Example Preparation of monolithic catalysts Reference Figure 1 The preparation method of the monolithic catalyst includes the following steps: S1. Degrease and rust removal treatment for foamed nickel; S2. The foamed nickel treated in step S1 is placed in a mixed solution of nickel nitrate, ammonium fluoride and urea, stirred for 30 min, and then placed in a reaction vessel and hydrothermally reacted at 120°C for 8 h to obtain the Ni-LDH / NF precursor. S3. The Ni-LDH / NF precursor obtained in step S2 is mixed with S powder and subjected to sulfidation heat treatment. Then it is placed in a tube furnace and calcined in an oxygen atmosphere. The temperature is increased by 5℃ / min, and the temperature is increased to 350℃. The reaction is carried out for 2 hours to obtain the NiS2 / NF monolithic catalyst.

[0025] Reference Figure 2 ,Depend on Figure 2 As shown in Figure A, the diffraction peak positions of the NiS2 / NF monolithic catalyst perfectly match the standard characteristic crystal plane diffraction peaks ((111), (200), (210), (211), (220), (311), (331), (220)) of pyrite-type NiS2, with no obvious impurity diffraction peaks appearing. This indicates that after hydrothermal-sulfidation heat treatment, the Ni-LDH precursor has been completely transformed into the target crystalline phase NiS2 active component, with high phase purity. Furthermore, the absence of strong diffraction peaks from the nickel foam substrate in the spectrum suggests that the NiS2 active component is uniformly loaded and well-crystallized on the nickel foam surface, providing a reliable phase basis for the efficient and stable operation of the catalyst.

[0026] Reference Figure 2 ,Depend on Figure 2As shown in Figure B, the low-magnification morphology (h, scale bar 200 μm) clearly reveals the three-dimensional interconnected porous framework structure of the nickel foam substrate. This structure possesses a high specific surface area and excellent mass and heat transfer properties, serving as a self-supporting carrier to provide uniform loading sites for the active components while facilitating fluid flow in industrial applications. The medium-magnification morphology (c, f, g, scale bar 30-100 μm) shows that the surface of the nickel foam framework is completely covered by a uniform and dense layer of NiS2 active components, with no exposed substrate areas. This indicates that the active components are uniformly loaded on the carrier surface, with tight interfacial bonding, preventing the loss of active components during catalysis. The high-magnification morphology (a, b, d, e, scale bar 1.5-20 μm) further reveals that the loaded NiS2 active components exhibit a three-dimensional nanoflower / nanofacial structure assembled from nanosheets. This hierarchical structure has a large specific surface area and abundant exposed active sites, significantly increasing the contact probability between CO2 and the catalytic active centers, thus improving the efficiency of the catalytic desorption reaction.

[0027] Example Example 1 The preparation method of a low-energy carbon capture and absorbent based on a polyetheramine-alcohol-water system includes the following steps: Using polyetheramine as the absorbent and organic alcohol and water as solvents, the polyetheramine, organic alcohol and deionized water were prepared in a molar ratio of 1:1:4, placed in a container, and ultrasonically homogenized to obtain a low-energy carbon capture and absorbent based on the polyetheramine-alcohol-water system. Among them, polyetheramine D230 is selected as the polyetheramine and n-propanol is selected as the organic alcohol.

[0028] Example 2 The preparation method of the low-energy carbon capture and absorbent based on the polyetheramine-alcohol-water system differs from Example 1 in that the polyetheramine, organic alcohol and deionized water are prepared in a molar ratio of 1:1:8, while the remaining steps are the same as in Example 1.

[0029] Comparative Example Comparative Example 1 The absorbent used is 200ml of single polyetheramine D230.

[0030] Comparative Example 2 The absorbent used is 200ml of single polyetheramine D400.

[0031] Comparative Example 3 The absorbent used is 200ml of single polyetheramine D2000.

[0032] Comparative Example 4 The absorbent was prepared by mixing polyetheramine D230 and n-propanol in a 1:1 molar ratio, placed in a container, and sonicated to obtain 200 ml of absorbent.

[0033] Comparative Example 5 The absorbent was prepared by mixing polyetheramine D230 and n-propanol in a molar ratio of 1:2, placing it in a container, and sonicating it to obtain 200ml of absorbent.

[0034] Comparative Example 6 The absorbent was prepared by mixing polyetheramine D230 and n-propanol in a molar ratio of 1:3, placing it in a container, and sonicating it to obtain 200ml of absorbent.

[0035] Comparative Example 7 The absorbent was prepared by mixing polyetheramine D230 and n-propanol in a molar ratio of 1:4, placing it in a container, and sonicating it to obtain 200ml of absorbent.

[0036] Comparative Example 8 The absorbent was prepared by mixing polyetheramine D230 and deionized water in a 1:1 molar ratio, placing it in a container, and sonicating it to obtain 200ml of absorbent.

[0037] Comparative Example 9 The absorbent was prepared by mixing polyetheramine D230, n-propanol and deionized water in a molar ratio of 1:1:16, placing it in a container, and sonicating it to obtain 200ml of absorbent.

[0038] Comparative Example 10 The absorbent is 200ml of 5M MEA.

[0039] Test case Test Example 1 Take the absorbents from Comparative Examples 1-3 respectively, and test them with a viscometer to measure their initial viscosity.

[0040] Reference Figure 3 The absorbent in Comparative Example 1 had the lowest initial viscosity at 9.24 mPa·s; the absorbent in Comparative Example 2 had a viscosity of 22.1 mPa·s; and the absorbent in Comparative Example 3 had a viscosity of 251 mPa·s. The absorbent in Comparative Example 1, polyetheramine D230, had the smallest molecular weight, short molecular chain, low ether bond content, and weak intermolecular forces, resulting in the lowest viscosity. In contrast, the absorbent in Comparative Example 3, polyetheramine D2000, had a significantly increased molecular weight, longer molecular chain, and enhanced intermolecular entanglement and interactions, leading to a sharp increase in viscosity. This invention aims to address the technical pain point of traditional amine-based absorbents, namely, the dramatic increase in viscosity and impaired mass transfer after absorption. Therefore, the initial viscosity of the absorbent components is crucial, and polyetheramine D230 was selected as the core component of the absorbent.

[0041] Test Example 2 The absorbents from Comparative Example 1, Comparative Example 4, Comparative Example 8, and Example 1 were used for CO2 capture. The capture process included the following steps: S1. A mixture of N2 and CO2 gas is bubbled into the four groups of absorbents mentioned above. A mass flow meter is used to precisely control the mixture of pure CO2 and N2 gas to simulate an industrial flue gas environment, ensuring that the CO2 concentration is 15% and the total flow rate is controlled at 400 mL / min. -1 And it is detected by an infrared CO2 analyzer; S2. Place the four groups of rich solutions (rich solution refers to the absorbent solution containing bound CO2 after CO2 absorption by the absorbent) from step S1 in a water bath, set the absorption temperature to 30~50℃, introduce simulated flue gas, and absorb for 1~8 hours. At the same time, collect the CO2 concentration in the analyzer.

[0042] Reference Figure 4 ,Depend on Figure 4 As shown in section a, the absorbent was the absorbent prepared in Example 1. The dynamic changes of its CO2 absorption rate over time (0-120 min) were tested at 30℃, 35℃, 40℃, and 50℃. In the initial absorption phase (0-60 min), the absorption rate remained at a relatively high level (approximately 5.1 mL) at all temperatures. L -1 s -1 The differences were not significant; at this point, the absorbent had sufficient active amine groups, and the reaction kinetics and mass transfer process were not significantly affected by temperature. In the later stages of absorption (60-120 min), the effect of temperature on the absorption rate decay gradually became more pronounced. The absorption rate decreased most rapidly at 30℃, approaching zero at 120 min; the rate decayed most slowly at 40℃, still maintaining approximately 0.7 mL at 120 min. L -1 s -1 The effective absorption rate was observed; the rate decayed slightly faster at 50°C than at 40°C, presumably because the higher temperature caused solvent evaporation or a reverse shift in the absorption equilibrium, reducing the effective absorption capacity. Therefore, 40°C is the optimal absorption temperature for the absorbent in this embodiment of the invention, balancing reaction kinetics and absorption capacity.

[0043] Reference Figure 4 ,Depend on Figure 4 As shown in section b, during the initial absorption period of 0-50 min, the absorption rate of each absorbent was approximately 5.1 mL. L -1 s -1The differences were not significant at this point, indicating sufficient active sites and the effect of the solvent was not yet apparent. As absorption proceeded, the absorbent in Comparative Example 1 showed the fastest decline, decreasing sharply after approximately 70 minutes and almost losing its absorption capacity by 100 minutes. This was attributed to the dramatic increase in viscosity, impaired mass transfer, and encapsulation of active sites after CO2 absorption in the pure amine system. The absorbent in Comparative Example 8 declined slightly slower than that in Comparative Example 1, indicating that water only partially improved viscosity and lacked stabilizing effect on the reaction intermediates. The absorbent in Comparative Example 4 showed a significantly slower decline, indicating that n-propanol could effectively reduce system viscosity, decrease product aggregation, and delay the rate of decline. The absorbent in Example 1 declined the slowest, maintaining approximately 1.9 mL at 220 minutes. L -1 s -1 The absorption rate of this absorbent is much higher than that of other absorbents, indicating that water promotes the dissociation of amino groups and n-propanol stabilizes the reaction intermediates. Together, they significantly reduce the viscosity of the system, ensure mass transfer efficiency, and significantly extend the effective working time of the absorbent.

[0044] Reference Figure 5 The absorbent in Comparative Example 1 had a viscosity of only 9.24 mPa before absorption. After absorbing CO2, the viscosity increases to 5099 mPa. This is because the products such as carbamates generated from the reaction of polyetheramine D230 with CO2 tend to aggregate, leading to a near loss of system fluidity and severely hindering gas-liquid mass transfer. This is completely consistent with the problem of "a sharp increase in viscosity after absorption by pure organic amines" in the background technology. The absorbents of Comparative Examples 4 and 8 had viscosities of 1620 mPa after absorbing CO2. s, 627mPa Although the viscosity of the absorbent in Example 1 was lower than that in Comparative Example 1, it was still at a relatively high level; the viscosity of the absorbent in Example 1 after absorbing CO2 was only 189 mPa. The viscosity of the amine system decreased by approximately 96% compared to Comparative Example 1, and by approximately 70% compared to Comparative Examples 4 and 8. This result indicates that the synergistic effect of n-propanol and water can effectively inhibit the aggregation of absorbed products, significantly improve the system's fluidity, and fundamentally solve the viscosity bottleneck of the pure amine system.

[0045] Reference Figure 5 The absorbent in Comparative Example 1 had the highest viscosity and the lowest desorption rate; the absorbent in Example 1 had the lowest viscosity and a significantly higher desorption rate than the absorbents in other systems. The high desorption rate in Example 1 was due to the low mass transfer resistance caused by the low viscosity, allowing CO2 molecules to diffuse rapidly from the liquid phase to the gas phase, making the desorption process easier.

[0046] Test Example 3 The absorbents from Comparative Examples 4-7, Comparative Example 9, and Examples 1-2 were used for CO2 capture, and the capture process was the same as in Test Example 1. After absorption, the solution was transferred to an oil bath, and desorption was started by heating. Desorption began when the solution temperature reached 60°C. The flow rate was measured using a soap film flow meter, and the readings on the power meter were recorded.

[0047] Reference Figure 6 ,Depend on Figure 6 As shown in Figure a, the absorption rate of all systems decreased with increasing absorption time, and the rate decay pattern differed significantly depending on the molar ratio. Specifically, the absorption rate of the absorbent in Comparative Example 6 decreased the slowest, maintaining approximately 2.0 mL at 220 min. L -1 s -1 The effective absorption rate of [the absorbent] was [the rate of absorption]; however, the absorption rates of the absorbents in Comparative Examples 4, 5, and 7 decreased more rapidly. Figure 6 As shown in section b, the absorbent in Comparative Example 6 has the highest CO2 absorption capacity, reaching 750.5 mL. L -1 It is significantly higher than other ratio systems.

[0048] Reference Figure 6 ,Depend on Figure 6 As can be seen from c, the absorption rate of the absorbent in Example 1 decreased the slowest, still maintaining approximately 2.0 mL at 220 min. L -1 s -1 The absorption rate of the absorbent in Example 2 and Comparative Example 9 was significantly higher than that of the binary system; however, the absorbent in Comparative Example 6 nearly lost its absorption capacity after approximately 200 minutes. Although the absorption rate decay of the absorbents in Example 2 and Comparative Example 9 was improved compared to the binary system, it was still faster than that of the absorbent in Example 1. Figure 6 As can be seen from d, the absorbent in Example 1 has the highest CO2 absorption capacity, reaching 933.4 mL. L -1 .

[0049] Test Example 4 Three groups of absorbents prepared in Example 1 were used for CO2 capture, and the capture process was the same as in Test Example 1. After absorption, desorption experiments were conducted at 95°C, 105°C, and 120°C, respectively.

[0050] Reference Figure 7 ,Depend on Figure 7 As can be seen from a, at 120℃, the absorbent in Example 1 exhibited the highest peak desorption rate (approximately 6.0 mL). s -1The initial desorption rate is rapid, with most CO2 desorption completed within 60 minutes, and the desorption rate approaches 0 by 80 minutes. At 105°C, the peak desorption rate of the absorbent in Example 1 is lower than that at 120°C, but the overall desorption process is gradual, and most CO2 desorption can still be completed within 80 minutes. At 95°C, although the peak desorption rate of the absorbent in Example 1 decreases somewhat, a stable desorption process can still be maintained, and effective regeneration can be completed within 80 minutes, proving that CO2 desorption can also be achieved at lower temperatures, providing a basis for catalytically assisted low-temperature regeneration.

[0051] Test Example 6 Three sets of absorbents prepared in Example 1 were used for CO2 capture, and the capture process was the same as in Test Example 1. During the process, viscosity was sampled and tested at ten-minute intervals. After the test sample was completed, it was poured back into the original solution, and the measurement was stopped after four hours of absorption.

[0052] Reference Figure 7 ,Depend on Figure 7 As shown in b, the viscosity of the absorbent system in Comparative Example 4 increases sharply as the absorption process proceeds, reaching nearly 1750 mPa after 200 minutes of absorption. The viscosity of the absorbent in Example 1 is almost completely lost, severely hindering the gas-liquid mass transfer process. This perfectly matches the technical bottleneck of the dramatic increase in viscosity after absorption by traditional amine-based absorbents. The absorbent in Example 1 exhibits an extremely gradual viscosity increase during absorption, with a viscosity of only about 150 mPa after 200 minutes of absorption. s, still maintains good liquidity.

[0053] Test Example 7 Reference Figure 8 This test example uses a programmed temperature rise method, and the temperature rise curve is shown as the dotted line in the figure. The test measures the desorption rate change of the absorbent in Comparative Example 4, Comparative Example 9, and Examples 1-2. Depend on Figure 8 As shown in section a, the absorbent of Example 1 exhibits a higher peak desorption rate, which occurs at a lower temperature range. The desorption rate decays rapidly after reaching its peak, dropping to a lower level within 40-50 minutes. In contrast, the absorbents of Comparative Examples 4 and 9 show lower peak desorption rates at higher temperatures, and the desorption process lasts significantly longer. The absorbent of Example 1 demonstrates a balanced desorption rate, balancing the desorption initiation speed and peak rate. Depend on Figure 8As shown in Figure b, the desorption equilibrium time of the absorbent in Example 1 decreases significantly with increasing water content. The absorbent in Example 1 completes most of the CO2 desorption in about 40 minutes, and its desorption efficiency is significantly higher than that of Comparative Example 4 and Comparative Example 9. With increasing water content, the desorption equilibrium time of the system further decreases, but the desorption capacity decreases slightly, indicating a trade-off between capacity and efficiency. Among these, the desorption capacity of the absorbent in Example 1 is close to that of the binary system, and the desorption efficiency is significantly improved, achieving the optimal balance between desorption capacity and efficiency.

[0054] Test Example 8 The absorbent prepared in Example 1 was subjected to a cyclic test. The solution was subjected to five absorption and desorption cycles to test the cyclic performance of the solution and to calculate the absorption capacity.

[0055] Reference Figure 9 ,Depend on Figure 9 As shown in Figure a, the absorbent of Example 1 has the highest CO2 desorption capacity, approximately 98 mL, significantly higher than the absorbents of Example 2 and Comparative Example 9, and also higher than the conventional 5M MEA of Comparative Example 10. This indicates that the absorbent of Example 1 can release more CO2 during the desorption stage, resulting in superior regeneration efficiency. Based on the heat load of the 5M MEA of Comparative Example 9, the regeneration heat load of the absorbent of Example 1 is only about 78% of it; the regeneration heat loads of the absorbents of Example 2 and Comparative Example 9 are approximately 88% and 95%, respectively. Although still lower than Comparative Example 10, their energy consumption advantage is not as significant as that of the absorbent of Example 1. With increasing water content, the regeneration heat load of the absorbents of Examples 1-2 gradually decreases, but the CO2 desorption capacity also decreases simultaneously, indicating a trade-off between energy consumption and capacity. The absorbent of Example 1 achieves the optimal balance between desorption capacity and regeneration energy consumption.

[0056] Reference Figure 9 ,Depend on Figure 9 As shown in section b, the CO2 absorption capacity of the absorbent in Example 1 did not decrease significantly during 5 cycles: the absorption capacity in the first cycle was 933.4 mL. L -1 The volumes for the second to fourth cycles were 900 mL each. L -1 913.7mL L -1 901.7mL L -1 The absorption capacity remained at 890.4 mL in the fifth cycle. L -1 The capacity retention rate is approximately 95.4%, and the decay rate is only about 4.6%, demonstrating excellent cycling stability.

[0057] Test Example 9 A set of absorbents prepared in Example 1 was used for CO2 capture, and the capture process was the same as in Test Example 1. After the absorption was saturated, the sample was transferred to an oil bath for desorption experiments, and the NiS2 / NF catalyst prepared in the preparation example was added. The oil bath temperature was set to 95°C, the flow rate at the outlet was recorded, and the desorption rate and desorption capacity were calculated.

[0058] Reference Figure 10 ,Depend on Figure 10 As shown in section a, the peak CO2 desorption rate of the system with added catalyst can reach approximately 8.2 mL. s -1 The peak rate in the blank group was only about 5.6 mL. s 1 This indicates that the catalyst effectively lowered the activation energy of the CO2 desorption reaction, promoting the kinetics of the desorption reaction. The desorption rate decreased rapidly after reaching its peak, dropping to near zero at approximately 55 min; while the desorption rate of the control group decreased slowly, maintaining a certain desorption rate at 80 min. This suggests that the catalyst significantly accelerated the desorption process, with most CO2 being desorbed in the early stages of the reaction, shortening the desorption cycle.

[0059] Reference Figure 10 ,Depend on Figure 10 As shown in Figure b, the desorption capacity of the system with added catalyst increased at a significantly faster rate than that of the control group over time. The catalytic system reached a desorption capacity of approximately 140 mL and stabilized after about 45 minutes; while the desorption capacity of the control group increased slowly, requiring about 60 minutes to reach a similar equilibrium capacity. This indicates that the catalyst significantly improved the overall efficiency of the desorption process and shortened the time required for absorbent regeneration. The final equilibrium desorption capacity of the two systems showed no significant difference, indicating that the NiS2 / NF monolithic catalyst only enhances the desorption rate through kinetic enhancement and does not affect the final regeneration degree of the absorbent. The desorption process still achieves complete regeneration, ensuring the recyclability of the absorbent.

[0060] The embodiments shown in this specification are only used to illustrate the technical solutions of the present invention and are intended to help those skilled in the art understand the principles and advantages of the present invention. They do not constitute a limitation on the scope of protection of the present invention. Although the present invention has been specifically described, those skilled in the art can still make any modifications, equivalent substitutions or other reasonable variations to the implementation methods without departing from the spirit and scope of the present invention. All equivalent technical solutions resulting therefrom should be considered within the scope of protection of this patent.

Claims

1. A low-energy carbon capture and absorbent based on a polyetheramine-alcohol-water system, characterized in that, The low-energy carbon capture and absorbent includes polyetheramine, organic alcohol and deionized water; The molar ratio of the polyetheramine, organic alcohol and deionized water is 1:(0.1~10):(0.1~10).

2. The low-energy carbon capture and absorbent based on the polyetheramine-alcohol-water system according to claim 1, characterized in that, The polyetheramine is polyetheramine D230.

3. The low-energy carbon capture and absorbent based on the polyetheramine-alcohol-water system according to claim 1, characterized in that, The organic alcohol is a C3-C4 monohydric alcohol; The difference between the boiling point of the organic alcohol and the boiling point of water does not exceed 20°C.

4. The low-energy carbon capture and absorbent based on the polyetheramine-alcohol-water system according to claim 3, characterized in that, The organic alcohol is n-propanol, isopropanol, n-butanol, or isobutanol.

5. A catalytic regeneration method for the low-energy carbon capture and absorbent according to any one of claims 1 to 4, characterized in that, Includes the following steps: Heat the CO2-saturated solution to the desorption temperature; and / or An integral catalyst is added to the rich solution to catalyze the desorption of CO2.

6. The catalytic regeneration method according to claim 5, characterized in that, The monolithic catalyst uses nickel foam as a carrier, and an active NiS2 layer is grown in situ on the surface of the nickel foam. The NiS2 active layer exhibits a nanosheet, nanowire, or nanoflower-like microstructure.

7. The catalytic regeneration method according to claim 5, characterized in that, The desorption temperature is 95~105℃.

8. The catalytic regeneration method according to claim 5, characterized in that, The desorption time is 0.5~2h.

9. The catalytic regeneration method according to claim 5, characterized in that, The preparation method of the monolithic catalyst is as follows: 1) Pretreatment of nickel foam; 2) Ni-LDH / NF precursors were synthesized on the surface of pretreated nickel foam using a hydrothermal or solvothermal method; 3) The Ni-LDH / NF precursor is mixed with a sulfur source and subjected to sulfidation heat treatment to obtain a NiS2 / NF monolithic catalyst.

10. The catalytic regeneration method according to claim 9, characterized in that, In step 2), the hydrothermal or solvothermal reaction temperature is 120~200℃, and the reaction time is 6~24h.

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