A method of carbon mineralization assisted by ionic liquid, composition and application thereof
By using ionic liquid catalysts to react alkaline earth metal-containing minerals with carbon dioxide under mild conditions to form carbonate materials, the problem of high energy consumption and poor economic feasibility of existing carbon mineralization technologies on an industrial scale has been solved, achieving efficient CO2 conversion and material production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- XIAN HUADA JIAOYANG GREEN TECH CO LTD
- Filing Date
- 2026-04-21
- Publication Date
- 2026-06-09
AI Technical Summary
Existing carbon mineralization technologies suffer from high energy consumption, equipment corrosion, and poor economic feasibility on an industrial scale. Conventional methods require harsh reaction conditions such as high temperature and high pressure, making it difficult to achieve efficient conversion of carbon dioxide into carbonate materials.
Using ionic liquids as catalysts, alkaline earth metal minerals are reacted with carbon dioxide in an aqueous medium under mild temperature and pressure to form carbonate materials. The ionic liquids then activate the metal ions and promote the conversion of carbon dioxide into carbonate or bicarbonate ions.
It significantly improves CO2 mineralization efficiency under mild conditions, reduces process energy consumption and equipment costs, avoids the formation of silicon passivation layers, and is suitable for carbon capture and the production of building materials.
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Figure CN122164226A_ABST
Abstract
Description
Technical Field
[0001] This application relates to an ion liquid-assisted carbon mineralization method, composition, and application thereof, belonging to the field of carbon mineralization technology. Background Technology
[0002] Anthropogenic carbon dioxide (CO2) emissions from fossil fuel use, industrial processing, and materials manufacturing are a core challenge in addressing global climate change. Within the industrial sector, cement and concrete production is one of the largest single contributors to global CO2 emissions, accounting for approximately 7-8% of annual anthropogenic emissions.
[0003] To reduce CO2 emissions, CCUS (Carbonized Carbon US) technology has been developed; however, many of these methods suffer from long-term storage risks, high capital costs, or limited durability. In contrast, carbon mineralization offers a thermodynamically favorable and permanent CO2 sequestration pathway by converting gaseous CO2 into environmentally friendly, permanently stable, and naturally abundant carbonate minerals such as calcium carbonate or magnesium carbonate.
[0004] In-situ carbon mineralization occurs naturally through weathering reactions, but requires a geological timescale. To enable industrial applications, ex-situ carbon mineralization processes have been developed to accelerate these reactions. Conventional ex-situ methods typically require harsh reaction conditions, such as high temperatures, high CO2 pressures, supercritical CO2 formation, enhanced mechanical activation, and / or the use of strong acids or bases. All of these measures aim to improve reaction kinetics, which is an effective strategy in laboratory or pilot-scale operations; however, such methods present significant challenges related to energy consumption, equipment corrosion, process safety, and overall economic viability at industrial scale. Summary of the Invention
[0005] According to one aspect of this application, an ion liquid-assisted carbon mineralization method is provided, which enables carbon mineralization mediated by an ion liquid in an aqueous medium to efficiently convert CO2 and alkaline earth metal-containing minerals into carbonate materials under mild temperature and pressure conditions.
[0006] The ionic liquid-assisted carbon mineralization method is characterized by comprising the following steps: The mineralization of carbon dioxide is achieved by reacting alkaline earth metal minerals with an activated catalyst in an aqueous reaction medium with an atmosphere containing carbon dioxide to form a solid product containing carbonates. The activation catalyst is an ionic liquid, which can activate metal ions in minerals containing alkaline earth metals and can convert carbon dioxide into bicarbonate or carbonate ions.
[0007] Optionally, the ion liquid-assisted carbon mineralization method includes the following steps: When minerals containing alkaline earth metals are added to water, a solution A containing alkaline earth metal ions is obtained in the presence of an activating catalyst. A carbon dioxide atmosphere is introduced into solution A to react and form a solid product containing carbonate.
[0008] Optionally, the reaction system is a water-enriched reaction system; the water content in the reaction medium is at least 50 wt%.
[0009] Preferably, the water content in the reaction medium is 70 wt%-99 wt%.
[0010] Optionally, the reaction temperature is 20℃-100℃.
[0011] Optionally, the carbon dioxide partial pressure in the carbon dioxide-containing atmosphere is 5 psi-900 psi.
[0012] Optionally, the amount of the ionic liquid used is 0.1 wt% to 25 wt% of the alkaline earth metal-containing mineral, based on the mass of the catalytically involved substance in the ionic liquid. Preferably, the amount of the ionic liquid used is 1 wt% to 10 wt% of the alkaline earth metal-containing mineral.
[0013] Optionally, the contact reaction time is 30 min to 24 h.
[0014] Optionally, the cation in the ionic liquid is a nitrogen-containing heterocyclic cation.
[0015] Optionally, the cation in the ionic liquid is independently selected from any one of substituted or unsubstituted imidazolium ions, substituted or unsubstituted benzimidazolium ions, and substituted or unsubstituted pyridinium ions; The substituents are selected from substituted or unsubstituted C1-C6 alkyl groups and substituted or unsubstituted C6-C12 aryl groups, and there are one or more substituents.
[0016] Optionally, the substituents of the C1-C6 alkyl groups and the C6-C12 aryl groups are amino groups.
[0017] In specific implementation, the C1-C6 alkyl groups can be straight-chain or branched alkyl groups with 1-6 carbon atoms, such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, hexane, n-pentane, 2-methylbutane, 2,2-dimethylpropane, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane.
[0018] The aryl group in C6-C12 can be phenyl, benzyl, naphthyl, biphenyl, etc.
[0019] The anion in the ionic liquid is selected from at least one of acetate, carbonate, bicarbonate, oxalate, phosphate, nitrate, halide, trifluoromethanesulfonate, and imide anions.
[0020] Optionally, the alkaline earth metal-containing mineral is selected from at least one of minerals containing alkaline earth metal oxides and silicate minerals; The silicate mineral is selected from at least one of wollastonite, olivine, serpentine, basalt, industrial slag, and mine tailings.
[0021] Minerals containing alkaline earth metal oxides, such as substances containing calcium oxide, like quicklime.
[0022] Optionally, when the alkaline earth metal-containing mineral is a silicate mineral, the reaction system has the effect of inhibiting silicon passivation on the surface of the solid product.
[0023] Optionally, the method further includes: The mixture after the reaction was subjected to solid-liquid separation. The obtained solid product was washed and dried to obtain the carbonate product. The ionic liquid is recovered from the separated liquid phase.
[0024] In another aspect, this application provides a composition for carbon mineralization, characterized in that it is used to mineralize carbon dioxide into a carbonate solid product, said system comprising at least: i) Silicate minerals; ii) At least 50 wt% water; and iii) Ionic liquids.
[0025] Optionally, the amount of the ionic liquid used is 0.1 wt% to 25 wt% of the alkaline earth metal mineral, based on the mass of the catalytic substances in the ionic liquid.
[0026] Optionally, the cation in the ionic liquid is a nitrogen-containing heterocyclic cation.
[0027] Optionally, the cation in the ionic liquid is independently selected from any one of substituted or unsubstituted imidazolium ions, substituted or unsubstituted benzimidazolium ions, and substituted or unsubstituted pyridinium ions; The substituents are selected from substituted or unsubstituted C1-C6 alkyl groups and substituted or unsubstituted C6-C12 aryl groups.
[0028] Optionally, the substituents of the C1-C6 alkyl groups and the C6-C12 aryl groups are amino groups.
[0029] The anion in the ionic liquid is selected from at least one of acetate, carbonate, bicarbonate, oxalate, phosphate, nitrate, halide, trifluoromethanesulfonate, and imide anions.
[0030] Optionally, the silicate mineral is selected from at least one of wollastonite, olivine, serpentine, basalt, industrial slag, and mine tailings.
[0031] Optionally, the composition has the effect of inhibiting silicon passivation on the surface of the solid product.
[0032] In another aspect, this application provides a carbonate material prepared according to the above-described ion liquid-assisted carbon mineralization method.
[0033] In this application, "silicate minerals" refers to minerals containing calcium, magnesium, iron, aluminum or combinations thereof, especially silicate minerals containing alkaline earth metal elements calcium and magnesium.
[0034] The beneficial effects that this application can produce include: 1) The ion liquid-assisted carbon mineralization method provided in this application, under the dual catalytic action of the ion liquid, can efficiently convert CO2 and alkaline earth metal-containing minerals into carbonate materials under mild temperature and pressure conditions, significantly improving the CO2 mineralization efficiency of minerals. This method is suitable for carbon capture, utilization, and storage (CCUS), as well as the production of carbonate materials for cementitious and building applications. Simultaneously, it effectively avoids the formation of a SiO2 passivation layer, overcoming the kinetic bottleneck of traditional mineralization processes and significantly reducing process energy consumption and equipment costs.
[0035] 2) The ion liquid-assisted carbon mineralization method provided in this application is adaptable to a variety of silicate minerals, covering different types of mineral raw materials such as calcium-based and magnesium-based minerals, and can flexibly select mineral raw materials according to industrial scenarios. Attached Figure Description
[0036] Figure 1 This is a schematic diagram of the ion liquid-assisted carbon mineralization method of this application. Figure 2 The TGA curves for Embodiments 5 and 8 of this application; Figure 3 The TGA curves are for Embodiments 20 and 22 of this application. Detailed Implementation
[0037] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.
[0038] Unless otherwise specified, the raw materials and catalysts used in the embodiments of this application were all purchased commercially.
[0039] According to one embodiment of this application, the ionic liquid (IL)-assisted carbon mineralization method includes the following steps: Add minerals containing alkaline earth metals to water, then add an ionic liquid to obtain solution A containing alkaline earth metal ions; if the corresponding silicate is used, it will also contain silicate ions.
[0040] A carbon dioxide atmosphere is introduced into solution A and the mixture is reacted at 20°C-100°C for 30 min-24 h to form a solid product containing carbonate.
[0041] The reaction system was subjected to solid-liquid separation, and the obtained solid product was washed and dried to obtain the carbonate product. The ionic liquid is recovered from the separated liquid phase.
[0042] This application provides an ion liquid-assisted carbon mineralization method, such as... Figure 1 As shown (using silicate minerals as an example), CO2 is converted into solid carbonates via heterogeneous minerals in an aqueous reaction medium containing ionic liquids. The mechanism is as follows: calcium- and / or magnesium-containing minerals are contacted with water and a catalytically effective amount of ionic liquid in a CO2 atmosphere, promoting the formation of alkaline earth metal carbonate products. During the reaction, the ionic liquid both promotes the release of alkaline earth metal ions from the minerals and activates CO2 into reactive bicarbonate or carbonate species, thereby achieving carbonate nucleation while maintaining dissolved silicon and inhibiting passivation.
[0043] Unlike conventional carbon mineralization processes that rely on harsh chemical additives, high temperatures, or supercritical CO2, this application enhances mineralization kinetics under mild conditions; at the same time, ionic liquids act as reaction mediators and catalysts, synergistically promoting CO2 activation and mineral dissolution.
[0044] During carbon mineralization, silicon released from silicate minerals remains in solution primarily as monomers or weakly oligomeric silicate species. The combination of a water-enriched environment and the presence of dissolved CO2 inhibits silicon polymerization and aggregation. Ultimately, the diffusion-limited silica layer forming on the mineral or carbonate surface is significantly reduced or eliminated, thus enabling sustained mineralization over extended reaction times.
[0045] In other words, the ionic liquid in the carbon mineralization method of this application is based on: a) promoting the release of alkaline earth metal ions from the silicate mineral lattice, and b) activating CO2 to HCO3. - or CO3 2- The synergistic effect of intermediates, c) stabilizing dissolved silicon species in solution, and d) inhibiting silicon aggregation and surface passivation enhances carbonization kinetics under mild conditions.
[0046] The method described in this application is applicable to various silicate minerals containing calcium, magnesium, or combinations thereof, including but not limited to wollastonite, olivine, serpentine, basalt, industrial slag, mine tailings, and mixtures thereof.
[0047] The minerals can be used in unprocessed, crushed, ground, or mechanically activated forms, with or without chemical pretreatment. Particle size, specific surface area, and mineralogical characteristics can be adjusted to optimize reaction kinetics while maintaining scalability.
[0048] In practice, the cation of the ionic liquid is selected from nitrogen-containing heterocyclic cations. Suitable cations include, but are not limited to, imidazolium, benzimidazolium, and pyridinium. In some embodiments, the cation contains alkyl, aryl, amino, or functionalized side chains that affect intermolecular forces, polarity, and interactions with mineral surfaces.
[0049] In some embodiments, cations having acidic hydrogen atoms on the heterocycle are particularly effective in promoting interactions with the silicate mineral lattice. In other embodiments, selectively substituted cations can enhance chemical stability, hydrophobicity, or resistance to degradation under plasma-assisted or high-temperature conditions.
[0050] Specifically, the ionic liquid cation used in the implementation of this application is an imidazole cation, specifically selected from one or more of the following: 1,3-dialkylimidazolium cation and aminoalkyl-substituted imidazole cation; wherein the alkyl group is a C1-C6 straight-chain or branched alkyl group, and the aminoalkyl group is an amino-containing C1-C6 alkyl group.
[0051] The anions of ionic liquids are selected from those that promote interaction with CO2 and / or alkaline earth metal ions, including but not limited to: acetate, carbonate, bicarbonate, oxalate, phosphate, nitrate, halide, trifluoromethanesulfonate and imide anions.
[0052] Anions capable of reversibly interacting with CO2 to form bicarbonate or carbonate species enhance mineralization kinetics by increasing the local concentration of active carbon species in aqueous media. Conversely, weakly coordinated or highly hydrophobic anions may exhibit reduced catalytic efficiency, but can be selected for specific process conditions or recovery strategies.
[0053] The selection of cation-anion pairs allows ionic liquids to be customized for specific mineral feedstocks, operating conditions, and reactor configurations.
[0054] Ionic liquids are present at a catalytic amount (the amount of ionic liquid required to promote mineralization without consuming a catalyst), typically 0.1 wt%–25 wt% relative to the mineral, but higher or lower loadings can be used depending on the mineral composition and the desired reaction rate.
[0055] The reaction process of this application is carried out in a water-rich environment, and the water content in the reaction medium is at least 50 wt%; preferably, the water content is at least 70 wt%; more preferably, the water content is 90 wt%-99 wt%.
[0056] High water content offers several advantages, including reduced viscosity, enhanced mass transfer, improved thermal management, and reduced ionic liquid consumption. Importantly, the water-enriched environment suppresses undesirable silicon aggregation and passivation phenomena commonly found in conventional aqueous mineralization processes.
[0057] The carbon dioxide supplied to the reaction can come from a pure CO2 stream, industrial flue gas, or a CO2-containing mixed stream. During implementation, the reaction proceeds at CO2 partial pressures ranging from 5 psi to 900 psi.
[0058] The reaction temperature is typically from about 20°C to about 100°C, but higher temperatures may be used in some embodiments. The reaction time is 30 min to 24 h, depending on the mineral type, particle size, and the choice of ionic liquid catalyst.
[0059] After the reaction is complete, the ionic liquid catalyst can be recovered through filtration, phase separation, solvent extraction, or other separation techniques. The recovered ionic liquid can be reused in subsequent carbon mineralization cycles with minimal loss of activity.
[0060] Example 1 Quicklime (1.00 g) was mixed with a catalytic amount (100 mg) of an ionic liquid containing 1-(3-aminopropyl)-3-methylimidazolium cation and bis(trifluoromethanesulfonyl)imide anion in a reaction vessel, and deionized water (5 mL) was added to form a slurry. The reaction vessel was sealed, purged with CO2 to remove residual gases, and maintained under a CO2 atmosphere at 5 psi. The reaction was carried out at ambient temperature (25 °C) for 1 h with continuous stirring. After the reaction was complete, the resulting slurry was filtered, and the solid product was washed several times with deionized water. The ionic liquid catalyst was recovered before collecting the solid product based on the physical and chemical properties of the ionic liquid. The recovered solid product was dried at 60 °C to remove residual water.
[0061] The embodiments of this application also carried out the carbon mineralization process under different reaction conditions: ① The implementation process is the same as the above carbon mineralization process, except that: the amount of ionic liquid used is 250 mg, the partial pressure of carbon dioxide in the atmosphere containing carbon dioxide is 900 psi, the reaction temperature is 100℃, and the reaction time is 10 h.
[0062] ② The implementation process is the same as the above carbon mineralization process, except that: the amount of ionic liquid used is 10 mg, the partial pressure of carbon dioxide in the atmosphere containing carbon dioxide is 100 psi, the reaction temperature is 50℃, and the reaction time is 2 h.
[0063] ③ The implementation process is the same as the carbon mineralization process described above, except that: the amount of ionic liquid used is 1 mg, the partial pressure of carbon dioxide in the atmosphere containing carbon dioxide is 10 psi, the reaction temperature is 80℃, and the reaction time is 30 min.
[0064] Example 2 A control experiment was conducted to evaluate the conversion of quicklime to calcium carbonate in the absence of an ionic liquid catalyst.
[0065] Quicklime (1.00 g) and deionized water (5 mL) were mixed in a sealed reaction vessel to form a water-enriched slurry. The vessel was purged with CO2 to remove residual gas, and then maintained under a carbon dioxide atmosphere with a CO2 partial pressure of 5 psi. The reaction was carried out at ambient temperature (25 °C) for approximately 1 h with continuous stirring. After the reaction was complete, the resulting slurry was filtered, and the solid product was washed several times with deionized water. The recovered solid product was dried for a sufficient time to remove residual water. Mass loss behavior was analyzed by TGA-DSC to determine baseline carbonate content, CO2 uptake, and mineralization efficiency.
[0066] Example 3 Quicklime (1.00 g) was reacted with a catalytic amount of an ionic liquid containing a functionalized imidazolium cation and a bis(trifluoromethylsulfonyl)imide anion. NH2 [Pmim][NTf2] (100 mg) was mixed in a reaction vessel, and deionized water (approximately 5 mL) was added to form a slurry. The reaction vessel was sealed, purged with CO2 to remove residual gases, and maintained under a CO2 atmosphere with a partial pressure of 5 psi. The reaction was carried out at ambient temperature (approximately 25 °C) for approximately 1 h with continuous stirring. After the reaction was complete, the resulting slurry was filtered, and the solid material was washed several times with deionized water. The ionic liquid catalyst was recovered based on the physical and chemical properties of the ionic liquid before collecting the solid product. The recovered solid product was dried under controlled conditions for a sufficient time to remove residual water. Mass loss behavior was analyzed by TGA-DSC to assess carbonate content, CO2 uptake, and mineralization efficiency.
[0067] Example 4 The difference from Example 2 is that the ionic liquid used is an ionic liquid [bmim][BF4] containing a nonfunctionalized imidazolium cation and a tetrafluoroborate anion.
[0068] Example 5 A control experiment was conducted to evaluate the conversion of wollastonite to calcium carbonate in the absence of an ionic liquid catalyst.
[0069] Wollastonite (2.00 g) was mixed with deionized water (10 mL) in a reactor to form a water-enriched slurry. Prior to the reaction, the reactor was purged multiple times with CO2 to remove residual gases, and then pressurized with CO2 to approximately 200 psi. The reaction was carried out at ambient temperature (approximately 25 °C) for approximately 1 h with continuous stirring. After the reaction was complete, the resulting slurry was filtered, and the solid product was washed multiple times with deionized water. The recovered solid product was dried for a sufficient time to remove residual water. Mass loss behavior was analyzed by TGA-DSC to determine baseline carbonate content, CO2 uptake, and mineralization efficiency.
[0070] Example 6 Wollastonite (2.00 g) was reacted with a catalytic amount of an ionic liquid containing a functionalized imidazolium cation and a bis(trifluoromethylsulfonyl)imide anion. NH2 [Pmim][NTf2] (200 mg) was mixed in the reactor. Deionized water (approximately 10 mL) was added to form a water-enriched slurry. The reactor was sealed and purged repeatedly with CO2 to remove residual gases. The reactor was then pressurized with CO2 to approximately 200 psi. The reaction was carried out at ambient temperature (approximately 25 °C) for approximately 2 h with continuous stirring. After the reaction was complete, the resulting slurry was filtered, and the solid product was washed repeatedly with deionized water. The ionic liquid catalyst was recovered before collecting the solid product, based on the physical and chemical properties of the ionic liquid. The recovered solid product was dried sufficiently to remove residual water. Mass loss behavior was analyzed by TGA-DSC to assess carbonate content, CO2 uptake, and mineralization efficiency.
[0071] Example 7 The difference from Example 6 is that the reaction temperature is 100°C and the reaction time is 1 h.
[0072] Example 8 Wollastonite (1.50 g) was reacted with a catalytic amount of an ionic liquid containing a functionalized imidazolium cation and a bis(trifluoromethanesulfonyl)imide anion. NH2[PmBim][NTf2] (150 mg) was mixed in the reactor. Deionized water (approximately 7.5 mL) was added to form a water-enriched slurry. The reactor was sealed and purged repeatedly with CO2 to remove residual gases. The reactor was then pressurized with CO2 to approximately 200 psi. The reaction was carried out at ambient temperature (approximately 25 °C) for approximately 1 h with continuous stirring. After the reaction was complete, the resulting slurry was filtered, and the solid product was washed repeatedly with deionized water. The ionic liquid catalyst was recovered before collecting the solid product, based on the physical and chemical properties of the ionic liquid. The recovered solid product was dried sufficiently to remove residual water. Mass loss behavior was analyzed by TGA-DSC to assess carbonate content, CO2 uptake, and mineralization efficiency.
[0073] Example 9 The difference from Example 8 is that the reaction temperature is 100°C.
[0074] Example 10 Wollastonite (1.51 g) was mixed in a reactor with a catalytic amount of the ionic liquid [bmBim][NTf2] (164 mg), which contains a nonfunctionalized imidazolium cation and a bis(trifluoromethanesulfonyl)imide anion. Approximately 7.5 mL of deionized water was added to form a water-enriched slurry. The reactor was sealed and purged repeatedly with CO2 to remove residual gases. The reactor was then pressurized with CO2 to approximately 200 psi. The reaction was carried out at ambient temperature (approximately 25 °C) for approximately 1 h with continuous stirring. After the reaction was complete, the resulting slurry was filtered, and the solid product was washed repeatedly with deionized water. The ionic liquid catalyst was recovered before collecting the solid product based on the physical and chemical properties of the ionic liquid. The recovered solid product was dried sufficiently to remove residual water. Mass loss behavior was analyzed by TGA-DSC to assess carbonate content, CO2 uptake, and mineralization efficiency.
[0075] Example 11 The difference from Example 8 is that the reaction time is extended to 16 h.
[0076] Example 12 A control experiment was conducted to evaluate the changes in wollastonite in the presence of an ionic liquid under an inert atmosphere without CO2.
[0077] Wollastonite (1.50 g) was mixed in a reactor with a catalytic amount of the ionic liquid [bmBim][NTf2] (150 mg), which contains a nonfunctionalized imidazolium cation and a bis(trifluoromethanesulfonyl)imide anion. Approximately 7.5 mL of deionized water was added to form a water-rich slurry. The reactor was sealed and purged repeatedly with nitrogen to remove residual gases. The reactor was then pressurized with nitrogen to approximately 200 psi. The reaction was carried out at ambient temperature (approximately 25 °C) for approximately 1 h with continuous stirring. After the reaction was complete, the resulting slurry was filtered, and the solid product was washed repeatedly with deionized water. The ionic liquid catalyst was recovered before collecting the solid product based on the physical and chemical properties of the ionic liquid. The recovered solid product was dried to remove residual water. Furthermore, inductively coupled plasma optical emission spectrometry (ICP-OES) was used to monitor mineral dissolution and ionic species in the reaction medium before and after the reaction.
[0078] Example 13 A control experiment was conducted to evaluate the changes in wollastonite in an inert aqueous environment in the absence of both CO2 and ionic liquid catalysts.
[0079] Wollastonite (1.50 g) was mixed with deionized water (approximately 7.5 mL) to form a slurry. The reactor was sealed and purged repeatedly with nitrogen to remove residual gases. The reactor was then pressurized with nitrogen to approximately 200 psi. The reaction was carried out at ambient temperature (approximately 25 °C) for approximately 1 h with continuous stirring. After the reaction was complete, the resulting slurry was filtered, and the solid product was washed repeatedly with deionized water. The recovered solid product was dried to remove residual water. Furthermore, inductively coupled plasma optical emission spectrometry (ICP-OES) was used to monitor mineral dissolution and ion species in the reaction medium before and after the reaction.
[0080] Example 14 A control experiment was conducted to evaluate the changes in wollastonite in an inert atmosphere in an aqueous environment under elevated temperature conditions in the absence of both CO2 and ionic liquid catalysts.
[0081] The difference from Example 14 is that the reaction temperature is 100°C.
[0082] Example 15 Ionic liquid-assisted mineralization experiments were conducted to assess the conversion of magnesium silicate minerals into magnesium carbonate.
[0083] Olivine (1.50 g) was mixed with a catalytic amount of the ionic liquid [bmBim][NTf2] (150 mg), which contains a nonfunctionalized imidazolium cation and a bis(trifluoromethanesulfonyl)imide anion, in a reactor. Deionized water (approximately 7.5 mL) was added to form a water-enriched slurry. The reactor was sealed and purged repeatedly with CO2 to remove residual gases. The reactor was then pressurized with CO2 to approximately 200 psi. The reaction was carried out at ambient temperature (approximately 25 °C) for approximately 1 h with continuous stirring. After the reaction was complete, the resulting slurry was filtered, and the solid product was washed repeatedly with deionized water. The ionic liquid catalyst was recovered before collecting the solid product based on the physical and chemical properties of the ionic liquid. The recovered solid product was dried sufficiently to remove residual water. Mass loss behavior was analyzed by TGA-DSC to assess carbonate content, CO2 uptake, and mineralization efficiency.
[0084] Example 16 To assess the conversion of magnesium silicate minerals into magnesium carbonate under elevated temperature and pressure conditions.
[0085] Olivine (2.00 g) was mixed with a catalytic amount of the ionic liquid [bmBim][NTf2] (200 mg), which contains a nonfunctionalized imidazolium cation and a bis(trifluoromethanesulfonyl)imide anion, in a reactor. Deionized water (approximately 10 mL) was added to form a water-enriched slurry. The reactor was sealed and purged repeatedly with CO2 to remove residual gases. The reactor was then pressurized with CO2 to approximately 250 psi and heated to 95 °C with continuous stirring for 30 min. After the reaction was complete, the reactor was cooled to ambient temperature, the resulting slurry was filtered, and the solid product was washed repeatedly with deionized water. The ionic liquid catalyst was recovered before collecting the solid product based on the physical and chemical properties of the ionic liquid. The recovered solid product was dried sufficiently to remove residual water. Mass loss behavior was analyzed by TGA-DSC to assess carbonate content, CO2 uptake, and mineralization efficiency.
[0086] Example 17 The difference from Example 16 is that the ionic liquid is an ionic liquid containing a functionalized imidazolium cation and a bis(trifluoromethanesulfonyl)imide anion. NH2 [Pmim][NTf2], reaction time 1 h.
[0087] Example 18 The difference from Example 17 is that the amount of ionic liquid used is 20 mg.
[0088] Example 19 The difference from Example 17 is that the ionic liquid is an ionic liquid [bmBim][OAc] containing a nonfunctionalized imidazolium cation and an acetate anion.
[0089] Example 20 The transformation of magnesium silicate minerals into magnesium carbonate under reaction conditions of no ionic liquid, high pressure CO2, and long duration.
[0090] Olivine (2.00 g) and deionized water (approximately 10 mL) were added to the reactor and mixed to form a water-enriched slurry. The reactor was sealed and purged multiple times with CO2 to remove residual gases. The reactor was then pressurized with CO2 to approximately 900 psi and heated to 95°C with continuous stirring for 24 h. After the reaction was complete, the reactor was cooled to ambient temperature, the resulting slurry was filtered, and the solid product was washed multiple times with deionized water. The recovered solid product was dried under controlled conditions for a sufficient time to remove residual water. Mass loss behavior was analyzed by TGA-DSC to assess carbonate content, CO2 uptake, and mineralization efficiency.
[0091] Example 21 The difference from Example 20 is that an ionic liquid [bmBim][OAc] containing a nonfunctionalized imidazolium cation and an acetate anion is added to participate in the reaction.
[0092] Example 22 The difference from Example 21 is that the ionic liquid is an ionic liquid containing a functionalized imidazolium cation and a bromide anion. NH2 Pmim][Br].
[0093] The reaction conditions and results in Examples 2-22 are summarized in Table 1.
[0094] Table 1
[0095] Note: To eliminate the interference of mineral background carbon mineralization on TGA test results, this study measured the background mass loss of pure CaO, wollastonite, and olivine in the 250-900℃ range. This loss is caused by the natural reaction of minerals with trace gases in the environment. All carbon mineralization experimental data have been adjusted to the corresponding background value. Specifically: a. The mass loss of pure CaO in the 250-900℃ range was 3.4%; b. The mass loss of wollastonite in the 250-900℃ range was 0.8%; c. The mass loss of olivine in the 250-900℃ range was 0.6%; d. The mass loss measurement range was 500-950℃ because Ca(OH)₂ decomposes in the 300-500℃ range; e. The amount of ionic liquid used was 1 wt%.
[0096] As shown in Table 1, different types of ionic liquids all enhance the carbon mineralization process using minerals containing alkaline earth metals (especially calcium and magnesium). Furthermore, temperature and ionic liquid exhibit a significant synergistic effect; in ionic liquid catalytic systems, increasing the reaction temperature can significantly accelerate the mineralization reaction kinetics. Taking the wollastonite / [NH₂PmBim][NTf₂] system as an example, the CO₂ absorption was 1.32 mmol / g at 25℃, increasing to 4.29 mmol / g at 100℃, an increase of 225%. The quicklime / [NH₂Pmim][NTf₂] system achieved a CO₂ absorption of 5.13 mmol / g at 100℃, which is 10.9 times that at 25℃ (0.47 mmol / g).
[0097] Furthermore, CO2 pressure is the core thermodynamic driving force of the mineralization reaction. Increasing the pressure can significantly increase the solubility of CO2 in ionic liquids, thereby improving the mineralization efficiency. Taking the olivine / [bmBim][OAc] system as an example, the CO2 absorption at 250 psi CO2 is 2.31 mmol / g, which increases to 4.67 mmol / g at 900 psi, an increase of 102%. In the wollastonite / [bmBim][NTf2] system, the CO2 absorption at 200 psi is 0.44 mmol / g, which increases to 1.23 mmol / g at 250 psi, an increase of 180%.
[0098] Figure 1 The TGA curves of the solid products in Examples 5 and 8 are shown in Table 1. It can be seen that without an ionic liquid catalyst, the wollastonite carbon mineralization product exhibits a slight mass loss at around 700°C, with a final mass loss of only 2.0%. However, under the same conditions, after the ionic liquid-assisted catalytic reaction, the wollastonite carbon mineralization product exhibits a significant and steep mass loss in the 650-800°C range, with a final mass loss of 5.8%, which is 2.9 times that of the group without a catalyst.
[0099] Figure 2 The TGA curves of the products from Examples 20 and 22 are shown in Table 1. It can be seen from the table that under the reaction conditions of 900 psi CO2, 95°C, and 24 h, the mass loss of the carbon mineralization product of Example 22 with added [NH2Pmim][Br] was 18.8%, and the corresponding CO2 absorption was 4.28 mmol / g, which is about 44% higher than the detection results of the carbon mineralization product of Example 20 without ionic liquid catalysis (13.0%, 2.97 mmol / g).
[0100] The results above demonstrate that the addition of ionic liquids not only significantly increases the amount of carbonate generated, but also optimizes the kinetics of the mineralization reaction, lowers the onset temperature of carbonate decomposition, and effectively avoids the formation of the SiO2 passivation layer, ensuring the continuous and efficient progress of the reaction.
[0101] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.
Claims
1. An ion liquid-assisted carbon mineralization method, characterized in that, Includes the following steps: The mineralization of carbon dioxide is achieved by reacting alkaline earth metal minerals with an activated catalyst in an aqueous reaction medium with an atmosphere containing carbon dioxide to form a solid product containing carbonates. The activation catalyst is an ionic liquid, which can activate metal ions in minerals containing alkaline earth metals and can convert carbon dioxide into bicarbonate or carbonate ions.
2. The method according to claim 1, characterized in that, Includes the following steps: When minerals containing alkaline earth metals are added to water, a solution A containing gold alkaline earth metal ions is obtained in the presence of an activating catalyst. A carbon dioxide atmosphere is introduced into solution A to react and form a solid product containing carbonate.
3. The method according to claim 1 or 2, characterized in that, The reaction system is a water enrichment reaction system; The reaction medium contains at least 50 wt% water.
4. The method according to claim 1 or 2, characterized in that, The reaction system is a water enrichment reaction system; The water content in the reaction medium is 70 wt%-99 wt%.
5. The method according to claim 1 or 2, characterized in that, The reaction temperature is 20℃-100℃.
6. The method according to claim 1 or 2, characterized in that, The carbon dioxide partial pressure in the atmosphere containing carbon dioxide is 5 psi-900 psi.
7. The method according to claim 1 or 2, characterized in that, The amount of the ionic liquid used is 0.1-25 wt% of the alkaline earth metal-containing mineral, based on the mass of the substances involved in catalysis in the ionic liquid.
8. The method according to claim 1 or 2, characterized in that, The contact reaction time is 30 min-24 h.
9. The method according to claim 1 or 2, characterized in that, The cations in the ionic liquid are nitrogen-containing heterocyclic cations.
10. The method according to claim 1 or 2, characterized in that, The cations in the ionic liquid are independently selected from any one of substituted or unsubstituted imidazolium ions, substituted or unsubstituted benzimidazolium ions, and substituted or unsubstituted pyridinium ions; The substituents are selected from substituted or unsubstituted C1-C6 alkyl groups and substituted or unsubstituted C6-C12 aryl groups.
11. The method according to claim 10, characterized in that, The substituents of the C1-C6 alkyl groups and the C6-C12 aryl groups are amino groups.
12. The method according to claim 1 or 2, characterized in that, The anion in the ionic liquid is selected from at least one of acetate, carbonate, bicarbonate, oxalate, phosphate, nitrate, halide, trifluoromethanesulfonate, and imide anions.
13. The method according to claim 1 or 2, characterized in that, The alkaline earth metal-containing minerals are selected from at least one of minerals containing alkaline earth metal oxides and silicate minerals. The silicate mineral is selected from at least one of wollastonite, olivine, serpentine, basalt, industrial slag, and mine tailings.
14. The method according to claim 13, characterized in that, When the alkaline earth metal-containing mineral is a silicate mineral, the reaction system has the effect of inhibiting silicon passivation on the surface of the solid product.
15. The method according to claim 1 or 2, characterized in that, The method further includes: The mixture after the reaction was subjected to solid-liquid separation and washing, and the obtained solid product was dried to obtain the carbonate product. The ionic liquid is recovered from the separated liquid phase.
16. A composition for carbon mineralization, characterized in that, For mineralizing carbon dioxide into carbonate solid products, the system comprises at least: i) Silicate minerals; ii) At least 50 wt% water; and iii) Ionic liquids.
17. The composition according to claim 16, characterized in that, The amount of the ionic liquid used is 0.1-25 wt% of the alkaline earth metal-containing mineral, based on the mass of the substances involved in catalysis in the ionic liquid.
18. The composition according to claim 16, characterized in that, The cations in the ionic liquid are nitrogen-containing heterocyclic cations.
19. The composition according to claim 16, characterized in that, The cations in the ionic liquid are independently selected from any one of substituted or unsubstituted imidazolium ions, substituted or unsubstituted benzimidazolium ions, and substituted or unsubstituted pyridinium ions; The substituents are selected from substituted or unsubstituted C1-C6 alkyl groups and substituted or unsubstituted C6-C12 aryl groups.
20. The composition according to claim 19, characterized in that, The substituents of the C1-C6 alkyl groups and the C6-C12 aryl groups are amino groups.
21. The composition according to claim 16, characterized in that, The anion in the ionic liquid is selected from at least one of acetate, carbonate, bicarbonate, oxalate, phosphate, nitrate, halide, trifluoromethanesulfonate, and imide anions.
22. The composition according to claim 16, characterized in that, The composition has the effect of inhibiting silicon passivation on the surface of the solid product.
23. A carbonate material, characterized in that, It is prepared by the ion liquid-assisted carbon mineralization method according to any one of claims 1-15.