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室温离子液体具有独特的气体选择溶解性,在二氧化碳(CO2)的捕集和分离中有很好的应用前景。综述了近年来CO2在不同离子液体中的溶解度研究进展,比较了CO2在常规离子液体和功能型离子液体中的不同溶解机制,分析、归纳了向离子液体中引入不同官能团对CO2溶解性能的影响规律,指出了离子液体捕集CO2的未来研究方向。 相似文献
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离子液体固定CO2及其转化利用的研究进展 总被引:2,自引:0,他引:2
综述了新型绿色溶剂离子液体在CO2固定和转化利用领域的应用研究进展.根据离子液体的结构特征和CO2的固定机理,离子液体固定CO2可以分为常规离子液体固定、功能化离子液体固定和离子液体固定转化.常规离子液体固定CO2为物理作用过程,功能化离子液体固定CO2为化学作用过程,而离子液体固定转化CO2的过程在固定CO2的同时又实现了CO2从工业废气直接到有用化学品的转变.因此,设计合成高效的功能化离子液体来实现CO2的固定转化一体化将具有重要的意义. 相似文献
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设计了以离子液体[APMIM]Br水溶液吸收-生成水合物捕获CO2工艺流程,并利用CO2在该离子水溶液中的溶解度数据和在其中生成CO2水合物的相平衡实验数据进行物料衡算. 考察了水含量、压力和液气流量比对气体吸收-水合物生成的CO2双重捕获效果的影响,对比了气体水合物与离子液体水溶液捕获CO2的能力. 结果表明,在较高压力和水含量条件下,水合物捕获CO2的效应强于离子液体溶液;较低压力下离子液体溶液吸收CO2起主要作用. 与纯水合物法相比,双捕获工艺具有一定优势,且突破了单纯水合物脱碳的压力和CO2含量要求高的局限性. 当原料气中CO2低于65%(j)时,系统的脱碳效率低于40%,对于CO2含量较低的气体,其CO2的脱除性能回归至单纯离子液体溶液体系. 相似文献
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《化工进展》2017,(8)
超临界二氧化碳(sc CO2)是一种环境友好型溶剂,它作为传统有机溶剂的替代品已被广泛应用于绿色化学过程的开发。其中,环氧化合物在超临界二氧化碳中制备环碳酸酯是实现二氧化碳高附加值转化的有效途径之一。本文回顾了近年来在超临界二氧化碳中合成环碳酸酯的研究进展,着重介绍了不同种类的催化剂,包括金属配合物、季盐、二元催化体系、离子液体、金属氧化物、有机小分子及其他类型催化剂在该反应体系中的应用,突出了超临界二氧化碳既作为溶剂,又作为反应物的双重优势。从经济和环境角度考虑,离子液体或季盐等有机催化剂具有更好的工业化应用前景。同时,指出了高效和绿色催化体系设计和创制是该研究领域的关键。 相似文献
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为改善离子液体1-胺丙基-3-甲基咪唑溴([APMIm][Br])水溶液CO_2水合物的生成特性,加入四氢呋喃(THF)形成复配溶液体系,研究复配体系中吸收CO_2同时生成水合物的特性。建立可视化高压反应釜,在273.15—288.15 K、0.5—3.5 MPa条件下,测试了不同浓度的[APMIm][Br]和THF体系中水合物-溶液-CO_2气体三相相平衡数据。实验结果表明:离子液体会抑制CO_2水合物生成,而THF能有效促进离子液体水溶液CO_2水合物的生成,水合物生成压力可大幅降低。基于离子液体水溶液缔合特性的活度系数模型理论和气体水合物的Van der Waals-Platteeuw模型理论,对复配溶液中CO_2气体水合物的相平衡进行了计算,与实验值相比,平均相对误差为1.84%。复配溶液对低压二氧化碳表现出良好的溶液吸收和气体水合物生成双效捕获能力。 相似文献
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Acidic ionic liquid-catalyzed synthesis of 1,3-diphenyi urea from aniline and carbon dioxide 下载免费PDF全文
以苯胺和二氧化碳为原料催化合成二苯基脲是一条绿色工艺路线,重点对Lewis酸类离子液体催化该反应性能进行了研究.考察了一系列碱性和Lewis酸性催化剂的催化性能,以及溶剂对该反应的影响,结果表明,以无水AlCl3为催化剂和乙腈为溶剂组成的反应体系效果较好.以氯铝酸类离子液体为催化剂兼溶剂,考察了离子液体阴阳离子、CO2初始压力、反应时间、反应温度以及催化剂用量等因素对二苯基脲合成反应的影响.结果表明,以[Bmim]Cl-AlCl3离子液体为催化剂兼溶剂,在CO2初始压力为1 MPa、反应时间为7h、反应温度为160℃、AlCl3/苯胺质量比为1 ∶ 1的条件下,苯胺的转化率、二苯基脲的收率及选择性分别为18.1%、17.9%和98.9%.此外,提出了[Bmim]Cl-AlCl3离子液体催化苯胺和二氧化碳的反应机理. 相似文献
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CO_2/[Bmim]Br-AlCl_3/苯体系相平衡研究 总被引:2,自引:0,他引:2
在温度40~80℃、压力1.50~12.00 Mpa条件下,测定了CO2在氯铝酸离子液体([Bmim]Br-AlCl3)中的溶解度:在60℃以及3.00~10.00 Mpa条件下,测定了CO2/[Bmim]Br-AlCl3苯三元体系中气液相平衡数据,获得了三组分物系的相图.实验结果表明:在低压条件下,CO2在离子液体中的溶解度(xco2)随压力增加而升高;当温度在40~80℃、压力9.00~10.00 Mpa范围内,xco2分别达到最大值.在CO2/[Bmim]Br-AlCl3/苯三元体系中,根据各组分的最初摩尔比的不同,平衡体系中分别会出现气-液两相及气-液-液三相.压力对富苯相中各组分影响较富离子液体更大:在60℃,lO.00 Mpa条件下,体系中有新相生成,气-液两相区转变为气-液-液三相区. 相似文献
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离子液体-超临界二氧化碳两相体系研究进展 总被引:2,自引:0,他引:2
简要介绍了离子液体-二氧化碳(IL-CO2)两相体系及IL面临的挑战.综述了利用CO2从ILs回收溶质、从有机溶剂中分离IL、IL-CO2体系的高压相行为、ILs在CO2相的溶度和IL-SCCO2体系分子水平的交互作用几个方面,讨论了压力、温度、阴离子的性质和阳离子烷基链长度对CO2溶度的影响,对尚存在的问题提出了建议,并对两相体系的发展方向进行了展望. 相似文献
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从工业废气中回收分离乙烯(C2H4)具有重要意义,选用了三种低黏度二氰胺类离子液体,分别测定了293.15~333.15 K下其密度、黏度等物化性质,研究了其对乙烯(C2H4)吸收性能。采用非随机(局部)双液体模型(NRTL)关联了三种二元体系溶解度数据,实验值与计算值的平均相对偏差均小于3%。结果表明,低黏度二氰胺类离子液体对C2H4气体吸收性能良好,其中阳离子侧链长度增加和羟基功能团引入可增强对C2H4溶解度。同时,离子液体1-丁基-3-甲基咪唑二氰胺盐([Bmim][DCN])经过3次的吸收解吸循环,仍可以保持较好的C2H4吸收性能,表明该离子液体循环稳定性好,而1-丁基-3-甲基咪唑二氰胺盐([Bmim][DCN])对乙烯吸收量较高,具有作为C2H4吸收剂的潜力。 相似文献
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Hiroshi MACHIDA Ryosuke TAGUCHI Yoshiyuki SATO Louw J. FLOURUSSE Cor J. PETERS Richard L. SMITH 《Frontiers of Chemical Science and Engineering》2009,3(1):12
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. 相似文献
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Sona Raeissi Louw J. Florusse Cor J. Peters 《American Institute of Chemical Engineers》2013,59(10):3886-3891
Knowledge of the solubility of carbon monoxide in ionic liquids is important for investigating the potential use of ionic liquids in reactions and gas separations. There is very limited information available on the capacity of ionic liquids to capture CO. The solubility of CO in 1‐butyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide was investigated experimentally up to temperatures and pressures of 460 K and 10 MPa, respectively. The solubility was shown to be only slightly temperature‐dependent, and the P–T diagram for a constant composition mixture is concave‐downward with a peak in pressure. By comparing the single‐gas solubility results of CO with various other gases in the same ionic liquid, it seems that ionic liquids can potentially be used as gas‐separating media. However, although the single‐gas solubilities vary considerably among some gases, further studies on mixed (multicomponent) gases should be carried out as the presence of other components can influence the solubility of each gas component. © 2013 American Institute of Chemical Engineers AIChE J, 59: 3886–3891, 2013 相似文献
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The effect on the melting temperature depression (MTD) of organic substances and ionic liquids caused by different types of pressurizing gases is analyzed. A high pressure gas produces a combined effect between solubility and pressure that causes the melting temperature to decrease. The authors have previously used phase equilibrium relations to correlate MTD of organic substances and ionic liquids under high pressure carbon dioxide, but other gases were not considered. The Peng–Robinson equation of state with the Wong–Sandler mixing rules showed to be appropriate for correlating the phase equilibrium in these high pressurized systems and is the model used is in this work. Three organic substances (naphthalene, biphenyl and octacosane) under high pressure produced by three gases (ethane, ethylene and carbon dioxide) for which experimental data on MTD are available were considered in this study. Then extension to an ionic liquid under high pressure carbon dioxide and high pressure ethylene was done. The proposed thermodynamic method and the model used show to have the necessary flexibility to acceptably correlate the MTD produced in these systems. 相似文献
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离子液体/盐双水相萃取技术的研究进展 总被引:2,自引:0,他引:2
离子液体/盐双水相萃取技术是一种新型的双水相萃取技术。它具有传统双水相萃取技术所不具备的诸多优点。本文介绍了离子液体/盐双水相体系的类型和特点,综述了离子液体/盐双水相萃取技术在生物分离、天然有机物的提取、有毒物质处理中的应用,指出了该技术目前存在的问题并提出今后发展的展望。 相似文献
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Hiroshi MACHIDA Ryosuke TAGUCHI Yoshiyuki SATO Louw J.FLORUSSE Cor J.PETERS Richard L.SMITH Jr 《Frontiers of Chemical Engineering in China》2009,3(1):12-19
Ionic liquids 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. 相似文献
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Sandra Dorbritz Wolfgang Ruth Udo Kragl 《Advanced Synthesis \u0026amp; Catalysis》2005,347(9):1273-1279
Understanding the behavior of ionic liquids on the molecular level is essential for explaining solubilizing or reaction processes, including catalytic reactions in ionic liquids or with ionic liquids as co‐solvent. Using mass spectrometry techniques it is possible to characterize their aggregate formation behavior, which depends on the used solvent. With increasing polarity of the solvent and decreasing ionic liquid concentration, the size of the formed aggregates decreases. From conductivity measurement curves “critical aggregate concentrations” were calculated, which confirm the results of mass spectrometry measurements. Addition of ionic liquids increases the solubility of acetophenone in water. This effect can be explained by the aggregate formation ability of ionic liquids. The findings can be used to explain the outstanding solubility and solvation properties of ionic liquids. 相似文献
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The high price and toxicity of ionic liquids(ILs) have limited the design and application of supported ionic liquid membranes(SILMs) for CO_2 separation in both academic and industrial fields. In this work, [Choline][Pro]/polyethylene glycol 200(PEG200) mixtures were selected to prepare novel SILMs because of their green and costeffective characterization, and the CO_2/N_2 separation with the prepared SILMs was investigated experimentally at temperatures from 308.15 to 343.15 K. The temperature effect on the permeability, solubility and diffusivity of CO_2 was modeled with the Arrhenius equation. A competitive performance of the prepared SILMs was observed with high CO_2 permeability ranged in 343.3–1798.6 barrer and high CO_2/N_2 selectivity from 7.9 to 34.8.It was also found that the CO_2 permeability increased 3 times by decreasing the viscosity of liquids from 370 to38 m Pa·s. In addition, the inherent mechanism behind the significant permeability enhancement was revealed based on the diffusion-reaction theory, i.e. with the addition of PEG200, the overall resistance was substantially decreased and the SILMs process was switched from diffusion-control to reaction-control. 相似文献
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Amino acid ionic liquids 总被引:1,自引:0,他引:1
The preparation of ionic liquids derived from amino acids, and their properties, are outlined. Since amino acids have both a carboxylic acid residue and an amino group in a single molecule, they can be used as either anions or cations. These groups are also useful in their ability to introduce functional group(s). Twenty different natural amino acids were used as anions, to couple with the 1-ethyl-3-methylimidazolium cation. The salts obtained were all liquid at room temperature. The properties of the resulting ionic liquids (AAILs) depend on the side groups of the amino acids involved. These AAILs, composed of an amino acid with some functional groups such as a hydrogen bonding group, a charged group, or an aromatic ring, had an increased glass transition (or melting) temperature and/or higher viscosity as a result of additional interactions among the ions. Viscosity is reduced and the decomposition temperature of imidazolium-type salts is improved by using the tetrabutylphosphonium cation. The chirality of AAILs was maintained even upon heating to 150 degrees C after acetylation of the free amino group. The amino group was also modified to introduce a strong acid group so as to form hydrophobic and chiral ionic liquids. Unique phase behavior of the resulting hydrophobic ionic liquids and water mixture is found; the mixture is clearly phase separated at room temperature, but the solubility of water in this IL increases upon cooling, to give a homogeneous solution. This phase change is reversible, and separation occurs again by raising the temperature a few degrees. It is extraordinary for an IL/water mixture to display such behavior with a lower critical solution temperature. Some likely applications are proposed for these amino acid derived ionic liquids. 相似文献