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1.
选用不同种类的室温型离子液体(RTILs)与胆碱脯氨酸离子液体进行混合分别制得[Choline][Pro]/[EMIm][N(CN)2]、[Choline][Pro]/[bmim][PF6]以及[Choline][Pro]/[HMIm][NTf2]混合离子液体,并将其应用于离子液体支撑液膜(SILMs)。考察操作温度、操作压差、RTILs种类和含量对SILMs分离CO2/N2性能的影响。结果表明胆碱脯氨酸/RTILs系列SILMs的CO2通量在343.3~1936.9 barrer之间变化并且CO2/N2选择性为10.3~34.8。对CO2膜过程内在机制探索表明随着[HMIm][NTf2]离子液体在混合离子液体中比例的增加,总阻力1/Km会呈现先降低后升高的趋势。与实验现象中随着[HMIm][NTf2]离子液体在混合离子液体中比例的增加CO2先升高后降低相符。  相似文献   

2.
为了进一步提高支撑型离子液体膜的制备效率及其CO2气体分离性能,将离子液体[Emim][BF4]以超临界流体沉积法负载到非对称的Al2O3支撑体内,制备了一系列支撑型离子液体膜,分别测定了CO2和N2两种纯气体在其中的渗透率,探究了制备参数(沉积时间、离子液体加入量和共溶剂加入量)对膜性能的影响规律.结果表明,基于[E...  相似文献   

3.
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。  相似文献   

4.
The effect of CO2‐philic additive polyethylene glycol (PEG) 200 in Matrimid 5218 on the separation performance of prepared membranes was evaluated in a binary gas mixture. Matrimid/PEG 200 flat‐sheet blended membranes with low PEG concentrations were prepared by the dense film‐casting method. Pure Matrimid and blended membranes were characterized by FTIR spectroscopy, scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, and permeation measurements. The addition of 4–5 % of PEG enhanced considerably the CO2 permeability of the Matrimid matrix. The best formulation, Matrimid/PEG 200 (96/4), showed in comparison to pure Matrimid a more than threefold increase in CO2 permeability and an increase in separation factor of about 40 %.  相似文献   

5.
刘佳佳  付雪  许映杰 《化工学报》2020,71(1):138-147
离子液体(ILs)作为一种新型的绿色溶剂在吸收和分离一氧化碳(CO)方面显示出了独特的优异性和潜在的应用价值。对近年来ILs参与CO吸收分离的研究工作进展进行了综述,主要包括常规ILs、阴离子功能化ILs、ILs/Cu (Ⅰ)盐和ILs支撑液膜。重点论述了CO在ILs中的溶解度及对其他气体的选择性,并与ILs吸收分离二氧化碳(CO2)性能进行了比较;着重讨论了阴阳离子种类、取代基类型、温度、压力等因素对ILs吸收分离CO性能的影响,并介绍了ILs吸收CO的机理。最后,对设计合成新型功能化ILs应用于高效吸收分离CO提出了一些建议。  相似文献   

6.
离子液体吸收CO_2的研究进展   总被引:2,自引:0,他引:2  
CO2的捕集、分离与利用已成为人类共同关心的重要课题。工业上,通常使用传统的有机胺水溶液或热钾碱溶液等脱除CO2。有机胺具有蒸气压,易产生挥发性有机物(VOCs)对环境造成污染;热钾碱溶液等脱除CO2需要较高操作温度因而能耗较高,生产过程经济性有待改善。离子液体具有几乎无蒸气压、热稳定性、结构可设计性等独特优点,在CO2分离领域的巨大应用潜力已成共识。本文结合课题组近期的研究工作,就国内外离子液体吸收CO2的主要研究成果进行综述。  相似文献   

7.
Innovative off-the-shelf CO2 capture approaches are burgeoning in the literature, among which, ionic liquids seem to have been omitted in the recent Intergovernmental Panel on Climate Change (IPCC) survey. Ionic liquids (ILs), because of their tunable properties, wide liquid range, reasonable thermal stability, and negligible vapor pressure, are emerging as promising candidates rivaling with conventional amine scrubbing. Due to substantial solubility, room-temperature ionic liquids (RTILs) are quite useful for CO2 separation from flue gases. Their absorption capacity can be greatly enhanced by functionalization with an amine moiety but with concurrent increase in viscosity making process handling difficult. However this downside can be overcome by making use of supported ionic-liquid membranes (SILMs), especially where high pressures and temperatures are involved. Moreover, due to negligible loss of ionic liquids during recycling, these technologies will also decrease the CO2 capture cost to a reasonable extent when employed on industrial scale. There is also need to look deeply into the noxious behavior of these unique species. Nevertheless, the flexibility in synthetic structure of ionic liquids may make them opportunistic in CO2 capture scenarios.  相似文献   

8.
离子液体对二氧化碳有良好的溶解性能,可以实现二氧化碳的固定与转化。超临界二氧化碳可以从离子液体/有机物体系中选择性萃取有机物,避免相间的交叉污染,实现离子液体的回收。从CO2在离子液体中的溶解度实验测定方法、CO2/离子液体二元体系高压相平衡测定、SC-CO2/离子液体/有机物的三元体系相平衡研究以及模型预测四个方面介绍了CO2/离子液体体系相平衡研究的最近进展,分析了这一研究领域的发展方向。  相似文献   

9.
功能型离子液体吸收电厂烟气CO_2的研究进展   总被引:1,自引:0,他引:1  
陈文  胡松  向军  孙路石  宋尧 《化工时刊》2010,24(2):52-60
CO2是目前排放量最大的温室气体,利用离子液体固定CO2已经成为CO2减排的重点研究方向之一。介绍了近几年来各种离子液体吸收CO2的研究历程以及研究成果,对比各种离子液体吸收性能的差异,并着重介绍了功能型离子液体捕获CO2的特点及其应用,突出其在CO2固定方面的诸多优势,并对离子液体的吸收机理进行了讨论,同时探讨离子液体在电厂烟气CO2处理过程中所面临的问题。  相似文献   

10.
因具有性质稳定、无挥发、CO2溶解能力强、产物易于分离、循环使用性高等特点,离子液体可望替代传统有机吸收剂用于气相CO2的固定分离.在简述其应用概况的基础上,主要综述了近期国内外此类离子液体(主要分为常规型和功能型两种)的合成方法的研究进展,并对功能型离子液体和相关材料的绿色合成方向进行了展望.  相似文献   

11.
The separation of carbon dioxide (CO2) is of great importance for environment protection and gas resource purification. The ionic liquids (ILs)-based gas separation membrane provides a new chance for efficient CO2 separation, while high permeability and selectivity of membranes is a great challenge. In this study, the influence of two protic ILs with different anion ([TMGH][Im] and [TMGH][PhO]) on the CO2 separation performance of the prepared ILs/Pebax blended membranes were systematically investigated at different temperature. The results showed the CO2 permeability exhibits the rising trend for ILs/Pebax blended membranes with the increment of IL content. Especially, the [TMGH][Im] with low viscosity and high CO2 absorption capacity leads to the blended membranes showing better CO2 permeability and ideal CO2 selectivity than that of membranes with [TMGH][PhO] at high IL content. Besides, with operating temperature increasing, the gas permeability of 20% (mass) [TMGH][Im]/Pebax blended membrane increases due to the decreasing viscosity of IL and the rising chain mobility of polymer. Inversely, the gas selectivity shows decreasing trend because CO2 absorption capacity obviously decreased at higher temperature.  相似文献   

12.
Off-gases with high content of carbon monoxide and hydrogen are often generated after a partial combustion of hydrocarbons in some industrial processes performed in reductive conditions. In these mixtures, both gases are usually accompanied by nitrogen. The selective recovery of these valuable compounds, H2 and CO, employing an efficient membrane technology is sought as a means to reduce the environmental footprint of the industrial activity. In this respect, this work provides fundamental knowledge on the transport properties of H2 through supported ionic liquid membranes (SILMs) prepared with an imidazolium-based room-temperature ionic liquid (RTIL) combined with either a chloride or a chlorocuprate(I) anion; this latter anion has already proved to enhance CO permeability across these SILMs due to a facilitated transport mechanism. Results showed that H2 is more permeable than CO and N2 through these RTILs due to its higher diffusivity. The H2/N2 and H2/CO selectivities through the chloride-based RTIL are 11 and 6, respectively. However, when the RTIL with the chlorocuprate(I) anion is employed instead of the chloride anion, the H2/N2 selectivity does not change whereas the H2/CO selectivity decreases, hence allowing obtaining a gas permeate stream with high content of both H2 and CO, and very low content of N2.  相似文献   

13.
The solubilities of gases in ionic liquids are important in evaluating ionic liquids as solvents for reactions involving permanent gases, as gas storage media, and as solvents for gas separations. Gas solubilities are also important in developing methods to separate solutes from ionic liquid solutions. Here we describe our measurements of the solubilities of CO2, CH4, C2H 6, C2H 4, O2, and N2 in 1-hexyl-3-methylpyridinium bis(trifluoromethylsulfonyl)imide and compare these results to our previous investigations. In addition, focus is placed on efforts to tailor ionic liquids to enhance the solubilities of some gases, with particular emphasis on carbon dioxide.  相似文献   

14.
Molecular dynamic simulation is used to study the microstructure of four kinds of ionic liquids (ILs), [Emim]PF6, [Emim][Tf2N], [PC6,6,6,14]PF6 and [PC6,6,6,14][Tf2N] in the capture process of CO2. Radial distribution function (RDF) and spatial distribution function (SDF) are used to analyze the microscopic properties of these systems. The calculated results show that the space distribution of CO2 around ILs determines the capability of ionic liquids for capturing CO2. Based on the analysis of SDF, CO2 and PF6- are overlapped partially around [Emim]+ in [Emim]PF6-CO2 mixture. When the anion is [Tf2N]-, cations are mainly distributed on one side of [Tf2N]- near N atom, and CO2 is concentrated on two sides near the fluoroalkylgroup (?CF3), and there is little overlapped district between cation and CO2. In [PC6,6,6,14]PF6-CO2 mixture, layered structure is found and CO2 is much nearer to PF6- than [PC6,6,6,14]+. Based on the analysis of RDF, in the phosphonium-based ILs, the highest distribution densities of anions and CO2 around cations are about 6 and 3 times as their average ones respectively, while in the imidazolium-based ILs, they are about 3 and 2 respectively, this means that the distributions of CO2 and anions around the imidazolium-based ILs are more evenly distributed than those around the phosphonium-based ILs.  相似文献   

15.
采用后嫁接法将碱性离子液体1-丁基-3-甲基咪唑的氢氧化物([Bmim]OH)分别负载到介孔硅胶、MCM-41分子筛和SBA-15分子筛上制备了非均相负载型离子液体,采用傅立叶变换红外光谱、N2吸附-脱附、元素分析和热重分析等手段对其表征,发现离子液体以共价键嫁接到硅胶上,且有较好的热稳定性。在无溶剂和温和的条件下,以非均相负载型离子液体为催化剂,研究了环氧丙烷与CO2环加成合成碳酸丙烯酯的反应,结果表明,3种非均相负载型离子液体均具有较好的催化性能,其中,[Bmim]OH/SiO2的催化性能最好,在最优条件下,环氧丙烷转化率可达99.1%,反应后催化剂经过滤即可分离回收利用,多次使用仍保持较高的反应活性。  相似文献   

16.
以多种氰基离子液体为前驱体,采用高温碳化法直接制备多孔碳氮材料,系统考察了离子液体前驱体阳离子结构、阴离子种类及合成条件等因素对碳化材料比表面积、氮元素含量及氮种类的影响,并研究其对CO2的吸附性能。结果表明,阴离子在聚合过程中起模板剂的作用。合成材料主要呈介孔结构,比表面积最高达732.6 m2/g,氮含量最高为9.9wt%,在温度25℃、压力1.8 MPa条件下,CO2的吸附量最高达20.9wt%。多孔碳氮材料经180℃真空加热后可完全脱附再生,再生稳定性良好。  相似文献   

17.
Water stable mixed-matrix membranes (MMMs) were developed to help control the global warming by capturing and sequestrating carbon dioxide (CO2) from post-combustion flue gas originated from burning of fossil fuels.MMMs of different compositions were prepared by doping glassy polymer Ultrason(R) S 6010 (US) with nanocrystals of zeolitic imidazolate frameworks (ZIF-300) in varying degrees.Solution-casting technique was used to fabricate various MMMs to optimize their CO2 capturing performance from both dry and wet gases.The prepared composite membranes indicated enhanced filler-polymer interfacial adhesion,consistent distribution of nanofiller,and thermally established matrix configuration.CO2 permeability of the membranes was enhanced as demonstrated by gas sorption and permeation experiments performed under both dry and wet conditions.As compared to neat Ultrason(R) membrane,CO2 permeability of the composite membrane doped with 40 wt% ZIF-300 nanocrystals was increased by four times without disturbing CO2/N2 ideal selectivity.In contrast to majority of previously reported membranes,key features of the fabricated MMMs include their structural stability under humid conditions coupled with better and unaffected gas separation performance.  相似文献   

18.
离子液体是一种饱和蒸汽压低、结构可设计、稳定性强、液态温度范围宽的绿色溶剂,同时对CO2又有较高的溶解度,因此成为当前CO2分离领域的研究热点材料。将离子液体和二维纳米材料结合得到的分离膜材料兼具离子液体和二维纳米材料的优势,在气体分离方面展现了良好的应用前景。其中,离子液体和氧化石墨烯的结合备受关注。针对这一热点问题,本工作综述了国内外通过氧化石墨烯、离子液体及离子液体?氧化石墨烯膜材料在CO2分离方面的研究和进展。相关研究表明,离子液体?氧化石墨烯膜材料具有较好的CO2选择性能、渗透性能和稳定性能,是一种非常有潜力的CO2分离材料。最后,提出了利用离子液体、氧化石墨烯及离子液体?氧化石墨烯膜材料进行CO2捕集分离的未来研究挑战和展望。  相似文献   

19.
Due to their negligible volatility,reasonable thermal stability,strong dissolubility,wide liquid range and tunability of structure and property,ionic liquids have been regarded as emerging candidate reagents for CO2 cap-ture from industries gases.In this review,the research progresses in CO2 capture using conventional ionic liquids,functionalized ionic liquids,supported ionic-liquids membranes,polymerized ionic liquids and mixtures of ionic liquids with some molecular solvents were investigated and reviewed.Discussion of relevant research fields was presented and the future developments were suggested.  相似文献   

20.
Room‐temperature ionic liquids serve as alternative solvents for volatile organic compounds in liquid‐liquid extraction and liquid membrane separation. 1‐Butyl‐3‐methylimidazolium tetrafluoroborate ([Bmim][BF4]) was applied for extraction and supported ionic liquid membranes (SILMs) to separate toluene and n‐heptane. A high separation factor of toluene was achieved due to the strong interaction between ionic liquid cations and toluene. The mass transfer performance of the SILM process was enhanced by higher operating temperature. With the increase of initial toluene concentration in the feed phase, the mass transfer flux and removal efficiency of the SILM process were improved, while the separation factor decreased. The mass transfer flux was growing with the increase of flow rate at both sides. The SILM process was stable over a long time period due to the high viscosity and low volatility of [Bmim][BF4].  相似文献   

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