Carbon capture agents, absorbents, devices, capture systems based on inorganic ammonia and applications

Abstract

This invention provides a carbon capture agent, absorbent, apparatus, capture system, and application based on inorganic ammonia. The carbon capture agent is used for the absorption and / or capture of carbon dioxide. The carbon dioxide capture agent comprises inorganic ammonia and a compounding agent; or, the carbon dioxide capture agent comprises a product obtained by mixing the inorganic ammonia and the compounding agent; the compounding agent comprises amino acids and / or organic amines. This invention can reduce the volatility of inorganic ammonia, reduce ammonia loss, and further reduce energy consumption in the carbon dioxide capture process.

Description

Technical Field

[0001] This invention relates to the treatment of carbon dioxide, and more particularly to a carbon capture agent, absorbent, apparatus, capture system and application based on inorganic ammonia. Background Technology

[0002] In recent years, global warming caused by greenhouse gases, especially carbon dioxide, has become a matter of great concern worldwide. However, the environmental problems caused by carbon dioxide remain very prominent. Therefore, how to effectively capture carbon dioxide from flue gas is an urgent problem to be solved.

[0003] Chinese invention patent CN113578025B (previous research by the inventor of this application) discloses a method and system for capturing carbon dioxide in flue gas. The method includes the following steps: conveying carbon dioxide-containing flue gas to an absorption device for carbon dioxide absorption, obtaining an absorbent and a purified gas; conveying the absorbent to the anode chamber of an electrolytic desorption device for desorption, obtaining a gas-liquid mixture containing a metal / ammonia coordination compound and carbon dioxide; performing gas-liquid separation on the gas-liquid mixture to obtain carbon dioxide gas and a separated liquid; conveying the separated liquid to the cathode chamber of the electrolytic desorption device, causing electrodeposition of the separated liquid in the cathode chamber, obtaining a deposited metal and an ammonia-containing solution; and conveying the ammonia-containing solution to the absorption device for further carbon dioxide absorption.

[0004] While the aforementioned patents can achieve the absorption and desorption of carbon dioxide in flue gas, inorganic ammonia is highly volatile. Therefore, directly using inorganic ammonia as a carbon capture agent can lead to significant losses of inorganic ammonia, and also result in unstable operation and poor cycle performance in the absorption and desorption of carbon dioxide.

[0005] In view of this, it is necessary to provide a carbon capture agent, absorbent, device, capture system and application based on inorganic ammonia to solve or at least alleviate the above-mentioned technical defects of the high volatility of inorganic ammonia. Summary of the Invention

[0006] The main objective of this invention is to provide a carbon capture agent, absorbent, device, capture system and application based on inorganic ammonia, aiming to solve the technical problem of the high volatility of inorganic ammonia.

[0007] To achieve the above objectives, the present invention provides a carbon capture agent based on inorganic ammonia, which is used for the absorption and / or capture of carbon dioxide;

[0008] The carbon scavenger comprises inorganic ammonia and a compounding agent; or, the carbon scavenger comprises a product obtained by mixing the inorganic ammonia and the compounding agent.

[0009] The compounding agent includes amino acids and / or organic amines.

[0010] Furthermore, the concentration of the inorganic ammonia is 0.5-8 mol / L;

[0011] And / or, the molar ratio of the inorganic ammonia to the compounding agent is 0.1-8:1.

[0012] Furthermore, the amino acid includes one or more of L-arginine, taurine, sarcosine, L-serine, glycine, β-alanine, and L-alanine.

[0013] Furthermore, the organic amine includes one or more of ethanolamine, aminoethylethanolamine, 2-amino-2-methyl-1-propanol, and N-methyldiethanolamine.

[0014] Furthermore, when the compounding agent includes the amino acid, the compounding agent also includes a regulator, which includes an alkaline hydroxide and / or an alkaline carbonate compound; the molar ratio of the amino acid to the regulator is 0.2-8:1.

[0015] Furthermore, the carbon trapping agent also includes a supporting electrolyte.

[0016] The present invention also provides a method for preparing a carbon capture agent, comprising: mixing inorganic ammonia and a compounding agent to obtain the carbon capture agent; wherein the compounding agent comprises amino acids and / or organic amines.

[0017] The present invention also provides the application of any of the carbon capture agents described above, or any of the carbon capture agents prepared as described above, in carbon dioxide absorption and / or carbon dioxide capture.

[0018] Furthermore, the carbon dioxide absorption step includes: contacting the carbon scavenger with the carbon dioxide-containing gas to be treated and absorbing it to obtain a carbon dioxide absorption liquid;

[0019] The carbon dioxide capture steps include:

[0020] The carbon capture agent is contacted with and absorbed by the gas to be treated containing carbon dioxide to obtain a carbon dioxide absorbent liquid.

[0021] The carbon dioxide absorbent is electrolyzed to desorb the carbon dioxide in the absorbent, resulting in a desorbed solution and desorbed carbon dioxide.

[0022] Furthermore, the carbon dioxide capture step further includes: electrolyzing the desorption solution to cause the metal ions bound to the carbon capture agent to undergo electrodeposition, thereby obtaining the carbon capture agent separated from the metal ions;

[0023] The desorption solution contains the carbon trapping agent, which is bound to metal ions originating from the electrode.

[0024] The present invention also provides a carbon dioxide absorption device, wherein the carbon dioxide absorption device comprises a carbon trapping agent as described above or a carbon trapping agent prepared by any of the preparation methods described above.

[0025] The present invention also provides a carbon dioxide capture system, which includes a carbon dioxide absorption device and a carbon dioxide desorption device;

[0026] The carbon dioxide absorption device contains a carbon trapping agent as described above or a carbon trapping agent prepared by any of the preparation methods described above;

[0027] The carbon dioxide absorption device and the carbon dioxide desorption device are connected to each other so as to continuously or intermittently transport the carbon dioxide absorbent generated in the carbon dioxide absorption device to the carbon dioxide desorption device, and the carbon dioxide desorption device has an electrolysis mechanism.

[0028] The present invention also provides a carbon dioxide absorbent liquid, which is used for the desorption and / or capture of carbon dioxide;

[0029] The carbon dioxide absorbent contains any of the carbon traps described above or the carbon traps prepared by any of the preparation methods described above, wherein the carbon traps are bound to carbon dioxide.

[0030] The present invention also provides an application of the carbon dioxide absorbent as described above in carbon dioxide desorption and / or carbon dioxide capture.

[0031] Furthermore, the carbon dioxide desorption step includes: electrolyzing the carbon dioxide absorbent to desorb carbon dioxide from the carbon dioxide absorbent;

[0032] The carbon dioxide capture process includes:

[0033] Obtain the carbon dioxide absorbent;

[0034] The carbon dioxide absorbent is electrolyzed to desorb the carbon dioxide from the absorbent.

[0035] The present invention also provides a carbon dioxide desorption device, wherein the anode chamber of the carbon dioxide desorption device contains a carbon dioxide absorbent as described above.

[0036] The present invention also provides a carbon dioxide capture system, which includes a carbon dioxide absorption device and a carbon dioxide desorption device;

[0037] The anode chamber of the carbon dioxide desorption device contains any of the carbon dioxide absorption liquids described above.

[0038] The anode chamber of the carbon dioxide desorption device is connected to the carbon dioxide absorption device to continuously or intermittently receive the carbon dioxide absorbent from the carbon dioxide absorption device.

[0039] Compared with the prior art, the present invention has at least the following advantages:

[0040] This invention proposes a carbon capture agent based on inorganic ammonia, which can reduce the volatility of inorganic ammonia and further reduce energy consumption in the carbon dioxide capture process, especially during long-term operation. Specifically, this invention significantly inhibits the volatility of inorganic ammonia by mixing it with amino acids and / or organic amines. ， This invention reduces ammonia loss, resulting in stable operation of the carbon dioxide capture system, excellent circulation performance, low maintenance costs, and is green, non-toxic, and environmentally friendly. Furthermore, it eliminates the need for a volatilization recovery system in the ammonia system, saving investment and simplifying the process. Detailed Implementation

[0041] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0043] It should be noted that existing technologies typically use inorganic ammonia (NH3) as the CO2 capture solvent and transition metals (zinc, nickel, copper, etc.) as the dielectric for efficient and low-consumption CO2 capture.

[0044] The existing technology mainly includes the following four steps (see Figure 1 in Chinese Invention with Authorization Announcement No. CN113578025B for details):

[0045] 1. Desulfurization and deammoniation pretreatment

[0046] The ammonia released from the absorber after the scrubbing water is recovered is used for flue gas desulfurization, achieving the dual functions of desulfurization and ammonia removal. Previous studies have shown that this process has a high ammonia recovery rate (>99%), a low ammonia emission concentration (<25 ppmv), and a high SO2 removal rate (>99%).

[0047] 2. CO2 ammonia absorption (absorption tower)

[0048] The pretreated flue gas enters the CO2 absorption tower and is coupled with the metal ions (Me) after ammonia regeneration by electrodeposition. 2+ )-Lean load / CO2-lean load ammonia solution contact decarbonization (reaction formula as follows), after collection Me 2+ -The lean / CO2-rich solution is sent to the anode chamber of the electrolytic cell.

[0049]

[0050] 3. Electrolytically coupled CO2 desorption (anode)

[0051] Metal ions have a significantly stronger coordination ability with ammonia than with CO2. In the anolyte chamber, electrochemically dissolved metal ions compete with CO2 for coordination with the amino group, thereby breaking the NH3-CO2 bond and releasing CO2 (reaction formula below). The desorbed Me... 2+ -The enriched / CO2-lean solution is sent to the cathode chamber of the electrolytic cell.

[0052]

[0053] Me (s) Transition metals such as zinc, copper, and nickel

[0054] 4. Electrodeposition coupled ammonia regeneration (cathode)

[0055] In the cathode chamber, Me(NH3) n 2+ Electrodeposition is Me (s) (The reaction formula is as follows), which promotes ammonia regeneration. At this time, the solution becomes Me. 2 + -Low-load / CO2-lean-load solution.

[0056]

[0057] After ammonia regeneration, the catholyte returns to the CO2 absorber for the next carbon capture cycle. An anion exchange membrane exists between the catholyte and anolyte; a heat exchanger exists between the absorber and the electrolytic cell; and a flash tank exists in the path from the anolyte to the catholyte for gas-liquid separation. After a certain number of cycles, the anode and cathode exchange fluids, or the flow directions of the anolyte and catholyte alternate periodically, to prevent complete dissolution of the anode metal.

[0058] However, the aforementioned prior art has at least the following drawbacks:

[0059] 1. Inorganic ammonia is highly volatile, resulting in significant losses, unstable operation, poor circulation performance, and high maintenance costs. Furthermore, inorganic ammonia is toxic and pollutes the environment.

[0060] 2. Inorganic ammonia volatilization recovery systems are complex, have lengthy processes, and high investment costs.

[0061] 3. Inorganic ammonia prevents further reduction in the energy consumption of the carbon dioxide absorption liquid electrolysis.

[0062] Based on this, the present invention provides a carbon capture agent based on inorganic ammonia, which is used for the absorption and / or capture of carbon dioxide; the carbon capture agent includes inorganic ammonia and a compounding agent.

[0063] It should be noted that inorganic ammonia, when used alone as a carbon capture agent, has the technical drawback of high volatility. Therefore, inorganic ammonia needs to be combined with the compounding agent; the compounding agent includes amino acids and / or organic amines.

[0064] Since the carbon scavenger is typically liquid, the inorganic ammonia usually exists in solution form, i.e., in the form of ammonia water, and has a certain concentration. The concentration of the inorganic ammonia can be 0.5 mol / L-8 mol / L, and more specifically 1 mol / L-5 mol / L. The concentration of the inorganic ammonia refers to the concentration of the inorganic ammonia in the carbon scavenger, or the initial concentration of the inorganic ammonia in the carbon scavenger (the concentration before the reaction). Therefore, the carbon scavenger may also include a solvent, which may include one or more of water and ammonia water.

[0065] It should be noted that the present invention does not specifically limit the types of amino acids and organic amines. To facilitate a detailed understanding of the present invention by those skilled in the art, some of the amino acids and organic amines mentioned in the present invention are listed below. Specifically, the vapor pressure of the amino acid at room temperature (25°C) may not exceed 1.31 kPa, i.e., it may be 0-1.31 kPa (at 25°C); the amino acid may include or be one or more of L-arginine, taurine, sarcosine, L-serine, glycine, β-alanine, and L-alanine; the organic amine refers to a class of nitrogen-containing compounds with an amino group (-NH2, -NH, -N) generated by the chemical reaction of organic substances with ammonia. The organic amines mentioned in the present invention typically have a pH greater than 7, do not contain the amino acids, and may include or be one or more of ethanolamine, aminoethylethanolamine, 2-amino-2-methyl-1-propanol (AMP), and N-methyldiethanolamine (MDEA).

[0066] Since the inorganic ammonia and the compounding agent may react chemically, the carbon scavenger in this invention can be understood as: the carbon scavenger includes the product of the inorganic ammonia and the compounding agent mixed together, and the mixing can be carried out in the solvent; that is, it can also be understood as: the carbon scavenger includes the product of the inorganic ammonia and the compounding agent mixed together in the solvent.

[0067] For example, referring to the following reaction formula, in the system of inorganic ammonia, the amino acid is deprotonated.

[0068]

[0069] Of course, there may be other technical mechanisms in this invention that are not yet fully understood, such as the change process of inorganic ammonia, but this does not affect the understanding of the technical solution and technical effect of this invention.

[0070] As a further explanation of the present invention, the molar ratio of the inorganic ammonia and the compounding agent can be 0.1-8:1, and more specifically 0.5-4:1.

[0071] In this invention, when the compound agent includes both the amino acid and the organic amine, the molar ratio of the amino acid and the organic amine can be 0.1-8:1.

[0072] Since the amino acid can also be deprotonated and activated by alkaline hydroxides and / or alkaline carbonates, when the compounding agent includes the amino acid, the compounding agent may also include a regulator, which includes alkaline hydroxides and / or alkaline carbonates; the molar ratio of the amino acid to the regulator is 0.2-8:1, and more preferably 1-2:1.

[0073] Furthermore, the alkaline hydroxide may include or be one or more of sodium hydroxide and potassium hydroxide; the alkaline carbonate may specifically be an alkaline bicarbonate, and the alkaline carbonate may include or be one or more of sodium bicarbonate and potassium bicarbonate.

[0074] Since the carbon dioxide capture in this invention involves carbon dioxide absorption and electrolytic desorption, in order to ensure the electrolytic desorption process, the carbon capture agent may also include a supporting electrolyte, such as potassium chloride.

[0075] The present invention also provides a method for preparing a carbon capture agent as described above, the carbon capture agent being used for the absorption and / or capture of carbon dioxide. The preparation method includes: mixing the inorganic ammonia and the compounding agent to obtain the carbon capture agent; the compounding agent includes the amino acid and / or the organic amine, and when the compounding agent includes the amino acid, the compounding agent may further include any of the regulators described above.

[0076] Typically, the carbon scavenger can be in liquid form, and the mixing of the organic amine and the compounding agent can be carried out in a solvent, which may include one or more of water and ammonia solution. In the embodiments and comparative examples of this invention, water is used as the solvent. Exemplarily, the inorganic ammonia exists in the form of an aqueous ammonia solution, and the carbon scavenger is obtained by mixing the aqueous ammonia solution and the compounding agent.

[0077] The present invention also provides the application of the carbon capture agent as described in any of the above claims in carbon dioxide absorption and / or carbon dioxide capture.

[0078] It should be noted that the carbon dioxide absorption refers to the use of a carbon capture agent to absorb carbon dioxide gas into a carbon dioxide absorption liquid, thereby separating the carbon dioxide gas from other gases or substances in the gas to be treated.

[0079] The carbon dioxide capture refers to the following steps: first, carbon dioxide gas is absorbed into a carbon dioxide absorbent using a carbon capture agent; then, carbon dioxide is released by carbon dioxide desorption (e.g., electrodesorption), thereby completing the capture and recovery of carbon dioxide and obtaining carbon dioxide products.

[0080] For example, the carbon dioxide absorption step may include:

[0081] The carbon capture agent is contacted with the gas to be treated containing carbon dioxide (e.g., flue gas containing carbon dioxide) and absorbed to obtain a carbon dioxide absorbent liquid after carbon dioxide absorption.

[0082] Specifically, the process of the carbon capture agent contacting the gas to be treated containing carbon dioxide can be carried out in a carbon dioxide absorption device, specifically in a carbon absorption tower.

[0083] The carbon dioxide capture steps may include:

[0084] The carbon scavenger is contacted with and absorbed by the carbon dioxide-containing gas to obtain a carbon dioxide absorbent; then, the carbon dioxide absorbent is electrolyzed to desorb the carbon dioxide in the absorbent, resulting in an desorbed liquid and desorbed carbon dioxide; wherein the desorbed liquid contains the carbon scavenger, and the carbon scavenger in the desorbed liquid is bound with metal ions originating from the electrode.

[0085] Specifically, the process of contacting the carbon capture agent with the carbon dioxide-containing gas to be treated can be carried out in a carbon dioxide absorption device to generate a carbon dioxide absorbent liquid after absorbing carbon dioxide; then, the carbon dioxide absorbent liquid is transported to a carbon dioxide desorption device to release the carbon dioxide bound to the carbon capture agent by electrolysis, thereby realizing the capture and recovery of carbon dioxide.

[0086] As a further explanation of the carbon dioxide capture, the carbon dioxide capture step may further include: electrolyzing the desorption solution to cause the metal ions bound to the carbon capture agent to undergo electrodeposition, thereby obtaining the carbon capture agent separated from the metal ions.

[0087] It is important to understand that carbon dioxide release typically occurs in the anode chamber of a carbon dioxide desorption device. That is, the electrodes in the anode chamber undergo electrodissolution, then combine with the carbon scavenging agent in the carbon dioxide absorbent, thereby separating the carbon dioxide from the carbon scavenging agent, completing the release of carbon dioxide, and obtaining the desorbed liquid. This can be accomplished using an external gas-liquid separation device, or the gas-liquid separation of carbon dioxide and the desorbed liquid can be completed directly in the anode chamber.

[0088] Electrolysis of the desorption solution is usually carried out in the cathode chamber of a carbon dioxide desorption device; that is, electrodeposition of the desorption solution occurs in the cathode chamber, thereby depositing metal ions in the desorption solution onto the electrodes of the cathode chamber, completing the separation of the carbon scavenger and the metal ions; the separated carbon scavenger can be reused for carbon dioxide absorption, thereby reforming the carbon dioxide absorbent.

[0089] The present invention also provides a carbon dioxide absorption device, wherein the carbon dioxide absorption device includes a carbon scavenger as described in any of the above claims. The carbon scavenger may be pre-placed in the absorption chamber of the carbon dioxide absorption device; alternatively, the carbon scavenger may be supplied to the carbon dioxide absorption device from the outside during the carbon dioxide absorption process.

[0090] The present invention also provides a carbon dioxide capture system, which includes a carbon dioxide absorption device and a carbon dioxide desorption device.

[0091] The carbon dioxide absorption device includes a carbon capture agent as described in any of the above descriptions; the carbon dioxide absorption device and the carbon dioxide desorption device are connected to each other so as to continuously or intermittently transport the carbon dioxide absorbent generated in the carbon dioxide absorption device to the carbon dioxide desorption device, and the carbon dioxide desorption device has an electrolysis mechanism.

[0092] It should be noted that, since the carbon dioxide desorption device is an electrodesorption device, the anode chamber and cathode chamber contained therein can be interchanged due to the influence of electrical properties. Therefore, the carbon dioxide absorption device can be connected to the anode chamber of the carbon dioxide desorption device, or it can be connected to the cathode chamber of the carbon dioxide desorption device at the same time, in order to adapt to the electrodesorption of carbon dioxide after the electrical properties are converted.

[0093] It should also be noted that, since the desorbed liquid needs to be electrolyzed in the cathode chamber after being generated in the anode chamber of the carbon dioxide desorption device, the anode chamber and cathode chamber of the carbon dioxide desorption device can be connected to each other to facilitate the transport of the desorbed liquid.

[0094] The present invention also provides a carbon dioxide absorbent for desorption and / or capture of carbon dioxide; the carbon dioxide absorbent contains a carbon capture agent as described in any of the above claims, the carbon capture agent in the carbon dioxide absorbent is bound to carbon dioxide, and is typically obtained by the carbon capture agent absorbing carbon dioxide.

[0095] The present invention also provides an application of the carbon dioxide absorbent as described in any one of the above claims in carbon dioxide desorption and / or carbon dioxide capture. It should be understood that, during the desorption process of the carbon dioxide absorbent, the volatilization rate of the carbon capture agent can be significantly reduced, and the electrolysis energy consumption during the desorption process can be reduced.

[0096] For example, the carbon dioxide desorption step may include:

[0097] Electrolysis is performed on the carbon dioxide absorbent as described in any of the above claims to desorb carbon dioxide from the absorbent, thereby obtaining carbon dioxide gas and a desorbent, wherein the carbon scavenger in the desorbent contains metal ions.

[0098] During the electrolysis process, the carbon dioxide absorbent can be placed in the anode chamber of the carbon dioxide desorption device, and the previously desorbed solution can be placed in the cathode chamber of the same device. This allows for simultaneous desorption of carbon dioxide in the anode chamber and electrodeposition of metal ions in the cathode chamber, while also enabling the re-acquisition of the carbon capture agent. The electrolysis current density can be 1 A / m³. 2 -400A / m 2 .

[0099] The carbon dioxide capture process may include:

[0100] Obtain a carbon dioxide absorbent as described in any of the above descriptions; the carbon dioxide absorbent may be derived from a carbon dioxide absorption device.

[0101] The carbon dioxide absorbent is subjected to any of the electrolysis methods described above to desorb the carbon dioxide from the absorbent.

[0102] The present invention also provides a carbon dioxide desorption device, wherein the anode chamber of the carbon dioxide desorption device contains the carbon dioxide absorbent as described. The carbon dioxide absorbent in the anode chamber can be supplied continuously from an external source or intermittently from an external source. When the carbon dioxide absorbent is continuously supplied to the anode chamber, the supply of the carbon dioxide absorbent and the electrolysis of the carbon dioxide absorbent can be performed simultaneously; when the carbon dioxide absorbent is intermittently supplied to the anode chamber, the carbon dioxide absorbent can be supplied to the anode chamber first, and then the carbon dioxide absorbent can be electrolyzed.

[0103] As a further description of the carbon dioxide desorption device, the carbon dioxide desorption device is typically an electrodesorption device, having an anode chamber and a cathode chamber separated by an anion exchange membrane. The electrodes in the anode chamber and the cathode chamber may contain transition metals (such as Zn, Cu, Ni, etc.). The electrodes in the anode chamber and the cathode chamber are electrically electrolyzed with an external power source. A cover may also be provided above the anode chamber and the cathode chamber to prevent gas escape. The anode chamber and the cathode chamber may also have channels for liquid and / or gas transport, as well as corresponding valves.

[0104] The present invention also provides a carbon dioxide capture system, comprising a carbon dioxide absorption device and a carbon dioxide desorption device; the anode chamber of the carbon dioxide desorption device contains a carbon dioxide absorbent as described above; the anode chamber of the carbon dioxide desorption device and the carbon absorbent outlet of the carbon dioxide absorption device are connected to each other to continuously or intermittently receive the carbon dioxide absorbent from the carbon dioxide absorption device. Wherein, when the anode chamber of the carbon dioxide desorption device is adjusted, the adjusted anode chamber can also be directly connected to the carbon absorbent outlet of the carbon dioxide absorption device.

[0105] The following are specific examples of the present invention:

[0106] Comparative Example 1: Inorganic Ammonia (NH3) System

[0107] 1. Simulation device for carbon dioxide desorption:

[0108] The simulation device includes a first electrolysis chamber and a second electrolysis chamber. The first electrolysis chamber contains a first electrode, and the second electrolysis chamber contains a second electrode. Both the first electrode and the second electrode are 7 cm long. 2The zinc plate has an electrode spacing of 2cm. Both the first and second electrodes are electrically connected to an external power source. When one electrolysis chamber is used as the anode chamber, the other electrolysis chamber is used as the cathode chamber. The first and second electrolysis chambers are separated by an anion exchange membrane, and the upper openings of both the first and second electrolysis chambers are sealed with the cover. Both the first and second electrolysis chambers are provided with carbon dioxide exhaust channels and electrolyte inlet and outlet channels.

[0109] 2. Preparation of anolyte and catholyte (M represents mol / L):

[0110] The anolyte in the anode chamber is a CO2-rich and zinc-poor solution (17.5 mL);

[0111] Anode solution composition: 0.2M Zn 2+ +1.2M CO2 + 2M ammonia + 2M potassium chloride.

[0112] The catholy solution located in the cathode chamber is a CO2-poor, zinc-rich solution (17.5 mL);

[0113] Cathodic solution composition: 0.7M Zn 2+ +0.5M CO2 + 2M ammonia + 2M potassium chloride.

[0114] 3. Simulation of electrolytic adsorption:

[0115] The prepared anolyte was used as the first electrolyte, and the prepared catholyte was used as the second electrolyte. Using the aforementioned simulation apparatus, the electrolyte was tested at 60°C and 100 A / m. 2 Constant current cyclic electrolysis is performed at a current density; the cyclic electrolysis is measured by the completion of the electrolysis of the first electrolyte in the cathode chamber.

[0116] The specific process of one cycle of electrolysis is as follows:

[0117] The first electrolyte was placed in the anode chamber, and the second electrolyte was placed in the cathode chamber. The mixture was subjected to an atmosphere of 60°C and 100 A / m. 2 The first electrolysis is carried out at a certain current density, thereby releasing and expelling carbon dioxide from the first electrolyte and causing zinc ions in the second electrolyte to electrodeposit. When the amount of CO2 discharged from the anode chamber reaches about 90% (at this time the carbon content of the solution is about 10% of the initial amount), the first electrolysis is ended. After the first electrolysis is completed, carbon dioxide is absorbed from the second electrolyte until the carbon dioxide concentration reaches saturation (based on pH stability).

[0118] The second electrolyte was placed in the anode chamber, and the first electrolyte was placed in the cathode chamber, at 60°C and 100 A / m. 2A second electrolysis is performed at a certain current density to release and remove carbon dioxide from the second electrolyte, and to cause zinc ions in the first electrolyte to electrodeposit. When the amount of CO2 removed from the anode chamber reaches about 90% (at which point the carbon content of the solution is about 10% of the initial amount), the second electrolysis is terminated. The first electrolyte is then subjected to carbon dioxide absorption until the carbon dioxide concentration reaches saturation (based on pH stability).

[0119] Then, subsequent cycles of electrolysis are performed.

[0120] The experimental results of this comparative example are as follows:

[0121] First cycle electrolysis: ammonia loss 5%, energy consumption 26kJ / molCO2;

[0122] Fifth cycle electrolysis: ammonia loss 28%, energy consumption 78kJ / molCO2;

[0123] The tenth cycle of electrolysis resulted in a 48% loss of ammonia and an energy consumption of 113 kJ / mol CO2.

[0124] Note: "Loss" refers to the amount of a corresponding component in the first electrolyte that is lost after electrolysis in the cathode chamber during this cycle of electrolysis, compared to its initial formulation (before the cycle of electrolysis).

[0125] "Energy consumption" refers to the power consumption generated by the first electrolyte in a single electrolysis in the cathode chamber during this electrolysis cycle.

[0126] Example 1: Inorganic ammonia + L-arginine

[0127] Compared to Comparative Example 1, this embodiment only replaces the 2M ammonia in the anolyte with 1M inorganic ammonia + 1M L-arginine; and replaces the 2M ammonia in the catholyte with 1M inorganic ammonia + 1M L-arginine, while keeping other conditions unchanged.

[0128] That is, the prepared anolyte and catholyte are:

[0129] Anode solution composition: 0.2M Zn 2+ +1.2M CO2 + 1M inorganic ammonia + 1M L-arginine + 2M potassium chloride;

[0130] Cathodic solution composition: 0.7M Zn 2+ +0.5M CO2 +1M inorganic ammonia +1M L-arginine +2M potassium chloride.

[0131] The experimental results of this embodiment are as follows:

[0132] First cycle electrolysis: Inorganic ammonia + L-arginine loss 0.3%, energy consumption 32kJ / molCO2;

[0133] Fifth cycle electrolysis: 1.2% loss of inorganic ammonia + L-arginine, energy consumption 36 kJ / mol CO2;

[0134] The tenth cycle of electrolysis resulted in a 2.4% loss of inorganic ammonia and L-arginine, with an energy consumption of 35 kJ / mol CO2.

[0135] Example 2: Inorganic ammonia + taurine

[0136] Compared to Comparative Example 1, this embodiment only replaces the 2M ammonia in the anolyte with 2M inorganic ammonia + 2M taurine; and replaces the 2M ammonia in the catholyte with 2M inorganic ammonia + 2M taurine, while keeping other conditions unchanged.

[0137] That is, the prepared anolyte and catholyte are:

[0138] Anode solution composition: 0.2M Zn 2+ +1.2M CO2 + 2M inorganic ammonia + 2M taurine + 2M potassium chloride;

[0139] Cathodic solution composition: 0.7M Zn 2+ +0.5M CO2 + 2M inorganic ammonia + 2M taurine + 2M potassium chloride.

[0140] The experimental results of this embodiment are as follows:

[0141] First cycle electrolysis: Inorganic ammonia + taurine loss 0.4%, energy consumption 29kJ / molCO2;

[0142] Fifth cycle electrolysis: Inorganic ammonia + taurine loss 2.1%, energy consumption 34kJ / molCO2;

[0143] The tenth cycle of electrolysis resulted in a 4.5% loss of inorganic ammonia and taurine, with an energy consumption of 39 kJ / mol CO2.

[0144] Example 3: Inorganic ammonia + sarcosine

[0145] Compared to Comparative Example 1, this embodiment only replaces the 2M ammonia in the anolyte with 2M inorganic ammonia + 2M sarcosine; and replaces the 2M ammonia in the catholyte with 2M inorganic ammonia + 2M sarcosine, while keeping other conditions unchanged.

[0146] That is, the prepared anolyte and catholyte are:

[0147] Anode solution composition: 0.2M Zn 2+ +1.2M CO2 + 2M inorganic ammonia + 2M sarcosine + 2M potassium chloride;

[0148] Cathodic solution composition: 0.7M Zn 2++0.5M CO2 + 2M inorganic ammonia + 2M sarcosine + 2M potassium chloride.

[0149] The experimental results of this embodiment are as follows:

[0150] First cycle electrolysis: 0.1% loss of inorganic ammonia and sarcosine, energy consumption 41 kJ / mol CO2;

[0151] Fifth cycle electrolysis: 0.4% loss of inorganic ammonia and sarcosine, energy consumption 43 kJ / mol CO2;

[0152] The tenth cycle of electrolysis resulted in a 0.9% loss of inorganic ammonia and sarcosine, with an energy consumption of 44 kJ / mol CO2.

[0153] Example 4: Inorganic ammonia + L-serine + NaOH

[0154] Compared to Comparative Example 1, this embodiment only replaces the 2M ammonia in the anolyte with 2M inorganic ammonia + 2M L-serine + 2M sodium hydroxide; and keeps the 2M inorganic ammonia + 2M L-serine + 2M sodium hydroxide in the catholyte unchanged, while keeping other conditions the same.

[0155] That is, the prepared anolyte and catholyte are:

[0156] Anode solution composition: 0.2M Zn 2+ +1.2M CO2 + 2M inorganic ammonia + 2M L-serine + 2M sodium hydroxide + 2M potassium chloride;

[0157] Cathodic solution composition: 0.7M Zn 2+ +0.5M CO2 + 2M inorganic ammonia + 2M L-serine + 2M sodium hydroxide + 2M potassium chloride.

[0158] The experimental results of this embodiment are as follows:

[0159] First cycle electrolysis: Inorganic ammonia + L-serine loss 0.4%, energy consumption 22kJ / molCO2;

[0160] Fifth cycle electrolysis: Inorganic ammonia + L-serine loss 1.5%, energy consumption 35kJ / molCO2;

[0161] The tenth cycle of electrolysis resulted in a 3.3% loss of inorganic ammonia and L-serine, with an energy consumption of 45 kJ / mol CO2.

[0162] Example 5: Inorganic ammonia + ethanolamine

[0163] Compared to Comparative Example 1, this embodiment only replaces the 2M ammonia in the anolyte with 1M inorganic ammonia + 1M ethanolamine; and replaces the 2M ammonia in the catholyte with 1M inorganic ammonia + 1M ethanolamine, while keeping other conditions unchanged.

[0164] That is, the prepared anolyte and catholyte are:

[0165] Anode solution composition: 0.2M Zn 2+ +1.2M CO2 + 1M inorganic ammonia + 1M ethanolamine + 2M potassium chloride;

[0166] Cathodic solution composition: 0.7M Zn 2+ +0.5M CO2 + 1M inorganic ammonia + 1M ethanolamine + 2M potassium chloride.

[0167] The experimental results of this embodiment are as follows:

[0168] First cycle electrolysis: Inorganic ammonia + ethanolamine loss 0.5%, energy consumption 22kJ / molCO2;

[0169] Fifth cycle electrolysis: 2% loss of inorganic ammonia + ethanolamine, energy consumption 31kJ / molCO2;

[0170] The tenth cycle of electrolysis resulted in a 4.3% loss of inorganic ammonia and ethanolamine, with an energy consumption of 35 kJ / mol CO2.

[0171] Example 6: Inorganic ammonia + ethanolamine

[0172] Compared to Comparative Example 1, this embodiment only replaces the 2M ammonia in the anolyte with 2M inorganic ammonia + 2M ethanolamine; and replaces the 2M ammonia in the catholyte with 2M inorganic ammonia + 2M ethanolamine, while keeping other conditions unchanged.

[0173] That is, the prepared anolyte and catholyte are:

[0174] Anode solution composition: 0.2M Zn 2+ +1.2M CO2 + 2M inorganic ammonia + 2M ethanolamine + 2M potassium chloride;

[0175] Cathodic solution composition: 0.7M Zn 2+ +0.5M CO2 + 2M inorganic ammonia + 2M ethanolamine + 2M potassium chloride.

[0176] The experimental results of this embodiment are as follows:

[0177] First cycle electrolysis: Inorganic ammonia + ethanolamine loss 0.4%, energy consumption 23kJ / molCO2;

[0178] Fifth cycle electrolysis: Inorganic ammonia + ethanolamine loss 2.3%, energy consumption 37kJ / molCO2;

[0179] The tenth cycle of electrolysis resulted in a 6.5% loss of inorganic ammonia and ethanolamine, with an energy consumption of 54 kJ / mol CO2.

[0180] Example 7: Inorganic ammonia + aminoethylethanolamine

[0181] Compared to Comparative Example 1, this embodiment only replaces the 2M ammonia in the anolyte with 2M inorganic ammonia + 2M aminoethyl ethanolamine; and replaces the 2M ammonia in the catholyte with 2M inorganic ammonia + 2M aminoethyl ethanolamine, while keeping other conditions unchanged.

[0182] That is, the prepared anolyte and catholyte are:

[0183] Anode solution composition: 0.2M Zn 2+ +1.2M CO2 + 2M inorganic ammonia + 2M aminoethylethanolamine + 2M potassium chloride;

[0184] Cathodic solution composition: 0.7M Zn 2+ +0.5M CO2 + 2M inorganic ammonia + 2M aminoethylethanolamine + 2M potassium chloride.

[0185] The experimental results of this embodiment are as follows:

[0186] First cycle electrolysis: Inorganic ammonia + aminoethylethanolamine loss 0.7%, energy consumption 32kJ / molCO2;

[0187] Fifth cycle electrolysis: Inorganic ammonia + aminoethylethanolamine loss 1.6%, energy consumption 39kJ / molCO2;

[0188] The tenth cycle of electrolysis resulted in a 3.2% loss of inorganic ammonia and aminoethyl ethanolamine, with an energy consumption of 36 kJ / mol CO2.

[0189] Example 8: Inorganic ammonia + aminoethylethanolamine + sarcosine

[0190] Compared to Comparative Example 1, this embodiment only replaces the 2M ammonia in the anolyte with 2M inorganic ammonia + 1M aminoethylethanolamine + 1M sarcosine; and replaces the 2M ammonia in the catholyte with 2M inorganic ammonia + 1M aminoethylethanolamine + 1M sarcosine, while keeping other conditions unchanged.

[0191] That is, the prepared anolyte and catholyte are:

[0192] Anode solution composition: 0.2M Zn 2+ +1.2M CO2 + 2M inorganic ammonia + 1M aminoethylethanolamine + 1M sarcosine + 2M potassium chloride;

[0193] Cathodic solution composition: 0.7M Zn 2+ +0.5M CO2 + 2M inorganic ammonia + 1M aminoethylethanolamine + 1M sarcosine + 2M potassium chloride.

[0194] The experimental results of this embodiment are as follows:

[0195] First cycle electrolysis: Inorganic ammonia + aminoethylethanolamine + sarcosine loss 0.2%, energy consumption 28kJ / molCO2;

[0196] Fifth cycle electrolysis: Inorganic ammonia + aminoethylethanolamine + sarcosine loss 0.7%, energy consumption 31kJ / molCO2;

[0197] The tenth cycle of electrolysis: inorganic ammonia + aminoethylethanolamine + sarcosine resulted in a 1.4% loss and an energy consumption of 29 kJ / mol CO2.

[0198] The above technical solutions of the present invention are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. All equivalent structural transformations made using the present invention specification under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. An application of a carbon scavenger in carbon dioxide capture, characterized in that, The carbon dioxide capture step includes: contacting the carbon capture agent with the gas to be treated containing carbon dioxide and absorbing it to obtain a carbon dioxide absorption liquid; The carbon dioxide absorbent is electrolyzed to desorb the carbon dioxide in the absorbent, resulting in an desorbed solution and desorbed carbon dioxide. The desorbed solution is then electrolyzed to cause the metal ions bound to the carbon scavenger to undergo electrodeposition, resulting in the carbon scavenger separated from the metal ions. The desorbed solution contains the carbon scavenger, which is bound to metal ions originating from the electrode. The carbon capture agent includes inorganic ammonia and a compounding agent; the compounding agent includes one or more of L-arginine, taurine, sarcosine, L-serine, ethanolamine, and aminoethylethanolamine.

2. The application according to claim 1, characterized in that, The concentration of the inorganic ammonia is 0.5-8 mol / L.

3. The application according to claim 1, characterized in that, The molar ratio of the inorganic ammonia to the compounding agent is 0.1-8:

1.

4. The application according to claim 1, characterized in that, When the compounding agent is L-serine, the compounding agent also includes a regulator, which includes an alkaline hydroxide and / or an alkaline carbonate compound; the molar ratio of L-serine to the regulator is 0.2-8:

1.

5. The application according to any one of claims 1-4, characterized in that, The carbon capture agent also includes a supporting electrolyte.

6. A carbon dioxide capture system, characterized in that, The carbon dioxide capture system includes a carbon dioxide absorption device and a carbon dioxide desorption device; The carbon dioxide absorption device contains a carbon trapping agent; The carbon dioxide absorption device and the carbon dioxide desorption device are connected to each other so as to continuously or intermittently transport the carbon dioxide absorbent generated in the carbon dioxide absorption device to the carbon dioxide desorption device. The carbon dioxide desorption device has an electrolysis mechanism. The carbon capture agent includes inorganic ammonia and a compounding agent; the compounding agent includes one or more of L-arginine, taurine, sarcosine, L-serine, ethanolamine, and aminoethylethanolamine.

7. The carbon dioxide capture system according to claim 6, characterized in that, The concentration of the inorganic ammonia is 0.5-8 mol / L.

8. The carbon dioxide capture system according to claim 6, characterized in that, The molar ratio of the inorganic ammonia to the compounding agent is 0.1-8:

1.

9. The carbon dioxide capture system according to claim 6, characterized in that, When the compounding agent is L-serine, the compounding agent also includes a regulator, which includes an alkaline hydroxide and / or an alkaline carbonate compound; the molar ratio of L-serine to the regulator is 0.2-8:

1.

10. The carbon dioxide capture system according to any one of claims 6-9, characterized in that, The carbon capture agent also includes a supporting electrolyte.

11. The application of a carbon dioxide absorbent in carbon dioxide desorption, characterized in that, The carbon dioxide absorbent is used for the desorption of carbon dioxide; the carbon dioxide absorbent contains a carbon trapping agent, which is bound to carbon dioxide. The carbon dioxide desorption step includes: electrolyzing the carbon dioxide absorbent to desorb carbon dioxide from the absorbent, obtaining a desorbed solution and desorbed carbon dioxide; electrolyzing the desorbed solution to electrodeposit metal ions bound to the carbon scavenger, obtaining the carbon scavenger separated from the metal ions; the desorbed solution contains the carbon scavenger, and the carbon scavenger is bound to metal ions from the electrode; The carbon capture agent includes inorganic ammonia and a compounding agent; the compounding agent includes one or more of L-arginine, taurine, sarcosine, L-serine, ethanolamine, and aminoethylethanolamine.

12. The application according to claim 11, characterized in that, The concentration of the inorganic ammonia is 0.5-8 mol / L.

13. The application according to claim 11, characterized in that, The molar ratio of the inorganic ammonia to the compounding agent is 0.1-8:

1.

14. The application according to claim 11, characterized in that, When the compounding agent is L-serine, the compounding agent also includes a regulator, which includes an alkaline hydroxide and / or an alkaline carbonate compound; the molar ratio of L-serine to the regulator is 0.2-8:

1.

15. The application according to any one of claims 11-14, characterized in that, The carbon capture agent also includes a supporting electrolyte.

16. An application of a carbon dioxide absorbent in carbon dioxide capture, characterized in that, The carbon dioxide absorbent is used for capturing carbon dioxide; the carbon dioxide absorbent contains a carbon capture agent, and the carbon capture agent is bound to carbon dioxide; The carbon dioxide capture process includes: obtaining the carbon dioxide absorbent; electrolyzing the carbon dioxide absorbent to desorb carbon dioxide from the absorbent, obtaining an desorbed solution and desorbed carbon dioxide; electrolyzing the desorbed solution to electrodeposit metal ions bound to the carbon scavenger, obtaining the carbon scavenger separated from the metal ions; the desorbed solution contains the carbon scavenger, and the carbon scavenger is bound to metal ions originating from the electrode; The carbon capture agent includes inorganic ammonia and a compounding agent; the compounding agent includes one or more of L-arginine, taurine, sarcosine, L-serine, ethanolamine, and aminoethylethanolamine.

17. The application according to claim 16, characterized in that, The concentration of the inorganic ammonia is 0.5-8 mol / L.

18. The application according to claim 16, characterized in that, The molar ratio of the inorganic ammonia to the compounding agent is 0.1-8:

1.

19. The application according to claim 16, characterized in that, When the compounding agent is L-serine, the compounding agent also includes a regulator, which includes an alkaline hydroxide and / or an alkaline carbonate compound; the molar ratio of L-serine to the regulator is 0.2-8:

1.

20. The application according to any one of claims 16-19, characterized in that, The carbon capture agent also includes a supporting electrolyte.

21. A carbon dioxide desorption device, characterized in that, The anode chamber of the carbon dioxide desorption device contains a carbon dioxide absorbent; the carbon dioxide absorbent is used for the desorption of carbon dioxide; the carbon dioxide absorbent contains a carbon trapping agent, and the carbon trapping agent is bound to carbon dioxide; The carbon capture agent includes inorganic ammonia and a compounding agent; the compounding agent includes one or more of L-arginine, taurine, sarcosine, L-serine, ethanolamine, and aminoethylethanolamine.

22. The carbon dioxide desorption apparatus according to claim 21, characterized in that, The concentration of the inorganic ammonia is 0.5-8 mol / L.

23. The carbon dioxide desorption apparatus according to claim 21, characterized in that, The molar ratio of the inorganic ammonia to the compounding agent is 0.1-8:

1.

24. The carbon dioxide desorption apparatus according to claim 21, characterized in that, When the compounding agent is L-serine, the compounding agent also includes a regulator, which includes an alkaline hydroxide and / or an alkaline carbonate compound; the molar ratio of L-serine to the regulator is 0.2-8:

1.

25. The carbon dioxide desorption apparatus according to any one of claims 21-24, characterized in that, The carbon capture agent also includes a supporting electrolyte.

26. A carbon dioxide capture system, characterized in that, The carbon dioxide capture system includes a carbon dioxide absorption device and a carbon dioxide desorption device; The anode chamber of the carbon dioxide desorption device contains a carbon dioxide absorbent; the carbon dioxide absorbent is used for the desorption of carbon dioxide; the carbon dioxide absorbent contains a carbon trapping agent, and the carbon trapping agent is bound to carbon dioxide; The carbon capture agent includes inorganic ammonia and a compounding agent; the compounding agent includes one or more of L-arginine, taurine, sarcosine, L-serine, ethanolamine, and aminoethylethanolamine; The anode chamber of the carbon dioxide desorption device is connected to the carbon dioxide absorption device to continuously or intermittently receive the carbon dioxide absorbent from the carbon dioxide absorption device.

27. The carbon dioxide capture system according to claim 26, characterized in that, The concentration of the inorganic ammonia is 0.5-8 mol / L.

28. The carbon dioxide capture system according to claim 26, characterized in that, The molar ratio of the inorganic ammonia to the compounding agent is 0.1-8:

1.

29. The carbon dioxide capture system according to claim 26, characterized in that, When the compounding agent is L-serine, the compounding agent also includes a regulator, which includes an alkaline hydroxide and / or an alkaline carbonate compound; the molar ratio of L-serine to the regulator is 0.2-8:

1.

30. The carbon dioxide capture system according to any one of claims 26-29, characterized in that, The carbon capture agent also includes a supporting electrolyte.

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