胆碱类低共融溶剂在CO_2捕集与分离中的应用

胆碱类低共融溶剂是一种新型的离子液体。它不仅具有传统离子液体的优点,还具有价格低廉、低毒、生物可降解等优势。对胆碱类低共融溶剂在CO2捕集与分离中所涉及的物理性质,如气体的溶解度、CO2的吸收-解吸、密度、稳定性、黏度和表面张力等进行考察,并分析了胆碱类低共融溶剂的结构对各物性的影响。通过与传统离子液体的对比,胆碱类低共融溶剂在CO2捕集与分离中的应用具有一定的优势,如CO2溶解度高,黏度低。然而,胆碱类低共融溶剂在气体的选择性分离、表面张力等的研究还不足,且热稳定性方面还存在瓶颈,因此,其在CO2捕集和分离中的应用还有待进一步探讨。     

负载型离子液体吸附分离CO2的研究现状及展望

人口增长与全球工业化的加速发展促使化石能源需求量逐年递增,由此导致大气中二氧化碳（CO₂）含量快速上升并引发了全球系列气候问题,“碳达峰·碳中和”背景下的CO₂减排刻不容缓。传统工业捕集CO₂方法由于能耗高、选择性较差、溶剂损耗大等问题限制了其大规模推广应用,离子液体因其极低挥发性、强的气体亲和性、可调的结构性质等特点在CO₂捕集分离领域逐渐显示出独特优势,但离子液体特别是功能化后通常黏度较高或室温呈固态,导致气液传质效果差或无法直接应用于吸收分离过程。负载型离子液体兼具离子液体和多孔材料的共同优势,不仅能提升选择性分离效果,有效避免离子液体直接吸收造成的高黏度,还可拓展离子液体应用范围,具有广阔的发展前景。重点总结了近些年物理和化学负载型离子液体在CO₂吸附分离方面的研究现状和进展,并对负载型离子液体捕集分离CO₂研究的发展趋势进行了展望。     

负载型离子液体吸附分离CO2的研究现状及展望

人口增长与全球工业化的加速发展促使化石能源需求量逐年递增,由此导致大气中二氧化碳（CO₂）含量快速上升并引发了全球系列气候问题,“碳达峰·碳中和”背景下的CO₂减排刻不容缓。传统工业捕集CO₂方法由于能耗高、选择性较差、溶剂损耗大等问题限制了其大规模推广应用,离子液体因其极低挥发性、强的气体亲和性、可调的结构性质等特点在CO₂捕集分离领域逐渐显示出独特优势,但离子液体特别是功能化后通常黏度较高或室温呈固态,导致气液传质效果差或无法直接应用于吸收分离过程。负载型离子液体兼具离子液体和多孔材料的共同优势,不仅能提升选择性分离效果,有效避免离子液体直接吸收造成的高黏度,还可拓展离子液体应用范围,具有广阔的发展前景。重点总结了近些年物理和化学负载型离子液体在CO₂吸附分离方面的研究现状和进展,并对负载型离子液体捕集分离CO₂研究的发展趋势进行了展望。     

超强碱离子液体-有机胺-水复配溶剂高效CO2捕集

CO₂捕集是实现碳减排的重要技术之一。其中，化学吸收法是一种有效的、适用于低CO₂分压的CO₂捕集技术。开发出一种高效、低能耗、环保的吸收剂是该领域的研究难点和热点。离子液体(ILs)作为一类绿色溶剂，在CO₂捕集中具有结构可调节、反应速率快、吸收量高等优势，但存在黏度大、价格昂贵等问题，本工作提出将超强碱离子液体1,8-二氮杂二环[5,4,0]十一碳-7-烯咪唑([HDBU][Im])与单乙醇胺(MEA)复配得到离子液体复配溶剂，来提高吸收剂的CO₂吸收量并降低吸收CO₂后溶剂的黏度。研究了离子液体浓度、吸收温度、CO₂分压等对离子液体复配溶剂捕集CO₂性能的影响，测定了离子液体复配溶剂在不同CO₂负荷下的密度和黏度等物性。结果表明，30wt%MEA+10wt%[HDBU][Im]具有较好的吸收能力，在40℃下，CO₂吸收量达到0.1453 g CO₂     

CO2捕集溶剂吸收法的研究进展

针对最主要的CO₂捕集方法溶剂吸收法，系统梳理了吸收剂有机胺、离子液体、低共熔溶剂以及相变溶剂在碳捕集领域的技术发展历程和现状，并分析了相关技术的发展趋势。目前溶剂吸收法主要以有机胺为主，但仍面临能耗和降解率高等问题，新型胺液溶剂的开发和应用还需时间验证。离子液体、低共熔溶剂和相变溶剂尽管具有替代有机胺捕集CO₂的潜力，但受成本和溶剂黏度的限制，依然面临着较多的技术挑战。因此，溶剂吸收法捕集CO₂技术开发仍有很大的提升空间。     

硅基离子液体微颗粒强化气体捕集与转化的研究进展

解决工业过程污染气体的过量排放问题,具有重要的科学和环境意义。离子液体(ILs)作为室温呈液态的绿色溶剂,在气体捕集转化方面具有独特的优势,但天然的高黏度特性严重阻碍了其工业应用。本团队基于多年研究发现,不执拗于大幅降低离子液体的黏度,而顺其自然,通过“微颗粒化”技术,实现离子液体于准静止状态的高效利用,是离子液体适应工业化的有效路径之一。鉴于此,综述了以二氧化硅(SiO₂)为介质的离子液体微颗粒,及其衍生的离子液体纳-微界面反应单元在气体捕集(VOCs和CO₂)和CO₂转化方面的应用研究进展,探讨了微颗粒化离子液体体系较传统体系的特性优势,并分析了离子液体“微颗粒化”的应用前景及工业可行性。     

离子液体和低共熔溶剂催化二氧化碳合成有机碳酸酯的研究进展

离子液体和低共熔溶剂因其良好的溶解与催化能力,可催化CO₂转化为高附加值化学品。本文综述了离子液体和低共熔溶剂催化CO₂转化为有机碳酸酯的研究进展,分析了CO₂与醇生成直链碳酸酯以及与环氧化物生成环状碳酸酯的反应机理;介绍了传统型、质子型、功能化离子液体以及由氯化胆碱、季铵盐与季膦盐、有机碱等作为氢键受体组成的低共熔溶剂,及其在CO₂转化为直链和环状碳酸酯反应中的催化性能;总结了此两类反应中离子液体和低共熔溶剂设计的基本规律;指出了CO₂转化反应中离子液体与低共熔溶剂存在的催化效率低、稳定性不高、后续分离困难等问题,后续研究可结合计算机辅助设计方法,探索更合适的阴阳离子/氢键供受体组合,获得更高效的催化体系。     

离子液体膜材料分离二氧化碳的研究进展

离子液体由于具有不易挥发、结构可调、对CO₂有良好的吸收性能等特点而成为当前CO₂分离领域的研究热点,但因高黏度和高成本问题而限制了其工业化应用。将离子液体与气体分离膜材料结合,得到的新型分离膜材料兼具离子液体和膜的优势,成为当前离子液体研究领域的趋势之一。针对这一热点问题,综述了离子液体支撑液膜、聚离子液体膜和离子液体共混/杂化膜在CO₂分离方面的研究现状和进展,讨论了离子液体结构和含量对膜分离性能、稳定性等的影响。相关研究表明,离子液体共混/杂化膜具有较高的分离性能和稳定性,是一种很有应用前景的CO₂分离材料。提出该领域的重点发展方向,即开发新的功能化离子液体共混/杂化膜材料是解决高渗透通量与高稳定性之间矛盾、强化CO₂分离性能的有效途径,深入研究离子液体共混/杂化膜的形成机制、气体在膜中的渗透行为以及CO₂分离机理。     

相变离子液体体系吸收分离CO2的研究现状及展望

全球工业化的迅速发展及人口增长使得化石燃料消耗不断增加，导致二氧化碳(CO₂)排放量逐年递增，引发全球化气候问题。醇胺吸收法目前在工业CO₂捕集应用最广泛，主要以单乙醇胺、甲基二乙醇胺等水溶液为吸收剂，存在溶剂损耗大、再生能耗高等问题，开发高效低能耗的新型吸收剂是实现CO₂大规模捕集的关键。离子液体具有气体亲和性好、蒸气压低、结构性质可调等特点，其中相变离子液体体系因节能潜力大被认为是新一代CO₂吸收剂，其吸收CO₂后由均相变为互不相溶的液-液或液-固两相，再生时仅需对CO₂富相加热处理，可有效减少吸收剂再生体积，降低再生能耗。重点总结近五年相变离子液体体系在CO₂分离的研究现状和进展，对不同相变行为的液-液和液-固相变离子液体体系分类阐述和讨论，并对其发展趋势进行展望。     

离子液体/金属有机框架复合材料捕集分离CO2

由于全球气候变化加剧和极端天气的增加,CO₂捕集分离已经不单单具有重要的战略意义,更关乎人类的生存。近年来,用于捕集分离CO₂的新型材料层出不穷,其中,离子液体(ionic liquids,ILs)具有可调变的化学结构和独特的物理化学性质,例如低挥发性、高热稳定性和较好的溶解性,从而引起了广泛关注。同时,金属有机框架结构材料(metal-organic frameworks,MOFs)在CO₂捕集分离方面也表现出优异性能。基于此,本文总结了ILs与MOFs相结合的ILs/MOFs复合材料捕集分离CO₂的研究进展,主要包括ILs负载于MOFs材料和对MOFs进行改性的吸附分离、MOFs材料分散于ILs中形成多孔液体的吸收分离、膜分离等方法的研究现状,同时,深入探讨了各方法的优点和不足之处,并对ILs/MOFs复合材料在CO₂捕集分离中的应用前景和发展趋势进行了展望。     

New process development and process evaluation for capturing CO2 in flue gas from power plants using ionic liquid [emim][Tf2N]

Using the ionic liquid [emim][Tf_2N] as a physical solvent, it was found by Aspen Plus simulation that it was possible to attempt to capture CO_2 from the flue gas discharged from the coal-fired unit of the power plant.Using the combination of model calculation and experimental determination, the density, isostatic heat capacity,viscosity, vapor pressure, thermal conductivity, surface tension and solubility of [emim][Tf_2N] were obtained.Based on the NRTL model, the Henry coefficient and NRTL binary interaction parameters of CO_2 dissolved in[emim][Tf_2N] were obtained by correlating [emim][Tf_2N] with the gas–liquid equilibrium data of CO_2. Firstly,the calculated relevant data is imported into Aspen Plus, and the whole process model of the ionic liquid absorption process is established. Then the absorption process is optimized according to the temperature distribution in the absorption tower to obtain a new absorption process. Finally, the density, constant pressure heat capacity,surface tension, thermal conductivity, and viscosity of [emim][Tf_2N] were changed to investigate the effect of ionic liquid properties on process energy consumption, solvent circulation and heat exchanger design. The results showed that based on the composition of the inlet gas stream to the absorbers, CO_2 with a capture rate of 90% and a mass purity higher than 99.5% was captured. These results indicate that the [emim][Tf_2N] could be used as a physical solvent for CO_2 capture from coal-fired units. In addition, the results will provide a theoretical basis for the design of new ionic liquids for CO_2 capture.     

Measurement and correlation of supercritical CO2 and ionic liquid systems for design of advanced unit operations

Ionicliquids combined with supercritical fluid technology hold great promise as working solvents for developing compact processes. Ionic liquids, which are organic molten salts, typically have extremely low volatility and high functionality, but possess high viscosities, surface tensions and low diffusion coefficients, which can limit their applicability. CO₂, on the other hand, especially in its supercritical state, is a green solvent that can be used advantageously when combined with the ionic liquid to provide viscosity and surface tension reduction and to promote mass transfer. The solubility of CO₂ in the ionic liquid is key to estimating the important physical properties that include partition coefficients, viscosities, densities, interfacial tensions, thermal conductivities and heat capacities needed in contactor design. In this work, we examine a subset of available high pressure pure component ionic liquid PVT data and high pressure CO₂ - ionic liquid solubility data and report new correlations for CO₂-ionic liquid systems with equations of state that have some industrial applications including: (1) general, (2) fuel desulfurization, (3) CO₂ capture, and (4) chiral separation. New measurements of solubility data for the CO₂ and 1-butyl-3-methylimidazolium octyl sulfate, [bmim][OcSO₄] system are reported and correlated. In the correlation of the CO₂ ionic liquid phase behavior, the Peng-Robinson and the Sanchez-Lacombe equations of state were considered and are compared. It is shown that excellent correlation of CO₂ solubility can be obtained with either equation and they share some common characteristics regarding interaction parameters. In the Sanchez-Lacombe equation, parameters that are derived from the supercritical region were found to be important for obtaining good correlation of the CO₂-ionic liquid solubility data.     

氨基功能型离子液体吸收CO2的性能

氨基功能型离子液体在常温常压下对CO₂具有较强的吸收选择性能,在分离固定CO₂方面具有较好的应用前景。合成了4种氨基功能型离子液体,对产物进行了IR和¹H NMR表征,探究了这些功能型离子液体的CO₂吸收性能及再生性能。结果表明,4种氨基功能型离子液体均具有强于常规型离子液体的CO₂吸收性能,再生性能良好,可循环使用;离子液体的CO₂溶解度受黏度影响显著,随吸收温度的升高而降低,随吸收压力的升高,吸收剂浓度的增加而增大;强化传质能提高再生效率,多次的再生对离子液体的吸收性能没有明显影响。     

Investigation of CO2 solubility in monoethanolamine hydrochloride based deep eutectic solvents and physical properties measurements

Deep eutectic solvents (DESs) have drawn a growing research interest for applications in a wide range of scientific and industrial arenas. However, a limited effort has been reported in the area of gas separation processes and particularly the carbon dioxide capture. This study introduces a novel set of DESs that were prepared by complexing ethylenediamine (EDA), monoethanolamine (MEA), tetraethylenepentamine (TEPA), triethylenetetramine (TETA) and diethylenetriamine (DETA) as hydrogen bond donors to monoethanolamide hydrochloride (EAHC) salt as a hydrogen bond acceptor. The absorption capacity of CO₂ was evaluated by exploiting a method based on measuring the pressure drop during the absorption process. The solubility of different DESs was studied at a temperature of 313.15 K and initial pressure of 0.8 MPa. The DES systems 1EAHC:9DETA, 1EAHC:9TETA and 1EAHC:9TEPA achieved the highest CO₂ solubility of 0.6611, 0.6572 and 0.7017 mol CO₂·(mole DES)^-1 respectively. The results showed that CO₂ solubility in the DESs increased with increasing the molar ratio of hydrogen bond donor. In addition, the CO₂ solubility increased as the number of amine groups in the solvent increases, therefore, increasing the alkyl chain length in the DESs, resulted in increasing the CO₂ solubility. FTIR analysis confirms the DES synthesis since no new functional group was identified. The FTIR spectra also revealed the carbamate formation in DES-CO₂ mixtures. In addition, the densities and viscosities of the synthesized DESs were also measured. The CO₂ initial investigation of reported DESs shows that these can be potential alternative for conventional solvents in CO₂ capture processes.     

离子液体支撑液膜的CO2/CH4分离性能

由于离子液体对CO₂具有较好的溶解选择性,离子液体支撑液膜分离CO₂越来越受到关注。比较了含3种不同阴离子的常规离子液体([bmim][BF₄]、[bmim][PF₆]、[bmim][Tf₂N])作为支撑液膜的液膜相分离CO₂/CH₄的性能,考察了咪唑环上烷基链长对离子液体支撑液膜性能的影响。考虑向离子液体中引入胺基和羧基等亲CO₂基团,制备了1-丁基-3-甲基咪唑丙氨酸离子液体([bmim][β-Ala]),考察了 [bmim][β-Ala]支撑液膜分离CO₂/CH₄的性能,并对在CO₂渗透测试前后的支撑液膜进行了FT-IR分析,发现氨基酸离子液体中的-NH₂和CO₂的较强作用以及该离子液体的高黏性影响了CO₂的透过性,使[Bmim][β-Ala]支撑液膜的CO₂透过率低。     

功能化离子液体在二氧化碳吸收分离中的应用

吸收及分离二氧化碳是降低碳排放和应对全球气候变化的主要策略之一，这就必然要求全球科技工作者注重开发具有选择性高效吸收分离二氧化碳的新材料和新路线。作为近20多年来发展的一类代表性的新材料，离子液体（尤其是功能化离子液体）具有独特的物理化学性质，例如几乎没有蒸气压、液态温度范围大、热稳定性和化学稳定性好、电化学窗口宽、不可燃、结构-性质可调控等。这些性质使离子液体在二氧化碳吸收及分离领域受到广泛关注。重点综述了近5年（2015~2019）来功能化离子液体吸收分离二氧化碳的研究进展, 主要内容包括单位点离子液体、多位点离子液体、基于功能化离子液体的混合物、功能化离子液体杂化材料对二氧化碳的吸收分离。同时, 对目前该领域的发展所面临的主要问题和进一步的研究工作进行了分析讨论。     

Recent progress of green sorbents-based technologies for low concentration CO2 capture

The increased concentration of CO₂ due to continuous breathing and no discharge of human beings in the manned closed space, like spacecraft and submarines, can be a threat to health and safety. Effective removal of low concentration CO₂ from the manned closed space is essential to meet the requirements of long-term space or deep-sea exploration, which is an international frontier and trend. Ionic liquids (ILs), as a widespread and green solvent, already showed its excellent performance on CO₂ capture and absorption, indicating its potential application in low concentration CO₂ capture. In this review, we first summarized the current methods and strategies for direct capture from low concentration CO₂ in both the atmosphere and manned closed spaces. Then, the multi-scale simulation methods of CO₂ capture by ionic liquids are described in detail, including screening ionic liquids by COSMO-RS methods, capture mechanism by density functional theory and molecular dynamics simulation, and absorption process by computational fluid dynamics simulation. Lastly, some typical IL-based green technologies for low concentration CO₂ capture, such as functionalized ILs, co-solvent systems with ILs, and supported materials based on ILs, are introduced, and analyzed the subtle possibility in manned closed spaces. Finally, we look forward to the technology and development of low concentration CO₂ capture, which can meet the needs of human survival in closed space and proposed that supported materials with ionic liquids have great advantages and infinite possibilities in the vital area.