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咪唑类离子液体合成及其应用研究 总被引:10,自引:1,他引:10
介绍了咪唑类离子液体的一般性质和合成方法,及其作为一种新型的化学溶剂广泛应用于化学合成、分离过程和电化学等方面,具有良好的发展前景。 相似文献
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《应用化工》2022,(12):2620-2623
采用微波辐射法合成了咪唑类离子液体1-烷基-3-甲基咪唑氯盐[C_nMim]Cl (n=12,14,16),测定了[C_nMim]Cl的电导率及表面张力。结果表明,随着烷基链长度的增加,临界胶束浓度(CMC)与最小表面张力(γCMC)减小,[C_(16)Mim]Cl的表面活性最好。胶束化热力学参数(ΔG_(mic)0、ΔH_(mic)0、ΔH_(mic)0、ΔS_(mic)0、ΔS_(mic)0)表明,[C_(12)Mim]Cl的胶束化是熵驱动;而对于[C_(14)Mim]Cl与[C_(16)Mim]Cl的胶束化而言,25℃为焓驱动,超过35℃为熵驱动。 相似文献
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通过两步法合成了阳离子含亲水性咪唑离子基和疏水烷基链结构、阴离子相同的1-乙基-3-甲基咪唑醋酸盐([Emim]Ac)、1-丁基-3-甲基咪唑醋酸盐([Bmim]Ac)、1-己基-3-甲基咪唑醋酸盐([Hmim]Ac)3种离子液体。利用红外光谱对其进行结构表征,并探究温度对pH的影响;考察温度、离子液体质量浓度、有机溶剂对电导率的影响;测定临界胶束浓度和溶解性。结果表明,[Emim]Ac、[Bmim]Ac、[Hmim]Ac碱性递减,其在不同溶剂中的电导率随温度(28~60℃)的升高、离子液体质量浓度(6~20 g/L)的增加而增大,且受溶剂性质影响;临界胶束浓度分别为11.46、9.92 g/L和9.72 g/L;其溶解性随溶剂极性的增强、侧链烷基的伸长而增大。 相似文献
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合成了一系列常规离子液体1-丁基-3-甲基咪唑四氟硼酸盐([Bmim][BF4])、1-丁基-3-甲基咪唑六氟磷酸盐([Bmim][PF6])、1-丁基-3-甲基咪唑双三氟甲磺酰亚胺盐([Bmim][NTf2])、1-丁基-3-甲基咪唑双氰胺盐([Bmim][DCA])、1-丁基-3-甲基咪唑硫氰酸盐([Bmim][SCN])、1-乙基-3-甲基咪唑硫氰酸盐([Emim][SCN])和N-丁基吡啶硫氰酸盐([BPy][SCN]),用智能重量分析仪(IGA)测定不同温度和分压下离子液体吸收二氯甲烷(DCM)的容量。结果表明,[Bmim][SCN]具有最高的二氯甲烷吸收容量(1.46 g/g, 303.15 K, 60 kPa),5次循环后吸收能力无明显下降,[Bmim][SCN]基本可完全再生,能循环使用。量化计算结果表明[SCN]?可与二氯甲烷形成氢键,增强其对二氯甲烷的吸收能力。 相似文献
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离子液体(ionic liquid)作为一种新型的有机溶剂,自从20世纪40年代以来,由于其特殊的性质被化学家重视,取得了长足的发展。现在离子液体已经被广泛应用到化学合成、化学分离和电化学等方面,并且得到了很好的结果。离子液体为化学提供了一个崭新的反应环境,具有良好的发展前景。本文介绍了离子液体的一般性质、制备方法与应用方面的内容。 相似文献
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咪唑类[PF_6]^-型离子液体萃取苯胺 总被引:1,自引:0,他引:1
研究了以咪唑类[PF6]-型室温离子液体1-丁基-3-甲基咪唑六氟磷酸盐([Bmim][PF6])、1-己基-3-甲基咪唑六氟磷酸盐([Hmim][PF6])和1-辛基-3-甲基咪唑六氟磷酸盐([Omim][PF6])对苯胺水溶液的萃取平衡。实验结果表明:pH值对分配系数的影响很大,在碱性条件下,分配系数较高;萃取过程属于吸热过程;经过四级错流萃取,废水可达到排放标准,萃取相中的苯胺回收率在90%左右,离子液体回收率〉90%,离子液体可以循环利用。 相似文献
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《分离科学与技术》2012,47(2):399-410
There is an increased interest in developing accurate tools to relate the physicochemical properties of ionic liquids (ILs) to their microscopic structure as this information is needed to speed up the design of new ionic liquids for chemical and industrial processes. Molecular models can be used for this purpose. We explore here the extended capabilities of a model previously developed in the context of soft-SAFT, by Andreu and Vega in 2007 to reproduce the thermodynamic behavior of imidazolium hexafluorophosphate-based ([Cnmim][PF6]) ionic liquids. The molecular parameters optimized in the previous work have been used here in a transferable manner; some new members of the [Cnmim][PF6] family have also been added, as new recent experimental data has been published. The interfacial tensions have been calculated using a Density Gradient Approach and the results have been compared with available experimental data. The solubility of carbon monoxide and hydrogen in those ILs has been studied in the range of temperatures and pressures of application for separation processes. Binary mixtures with other imidazolium ionic liquids with different anions have been calculated, in a predictive manner. Finally, calculations of mixtures of ionic liquids with water also show very good agreement with experimental data. This work highlights the importance of using a simple but robust thermodynamic model, including the right level of interactions, to accurately describe the properties of these highly non-ideal systems. 相似文献
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Abstract We tested dissolution and regeneration of poplar wood using 1-butyl-3-methylimidazolium chloride ([C4mim]Cl) and 1-butyl-3-methylimidazolium acetate ([C4mim]OAc). When 5wt% of poplar sawdust in [C4mim]OAc was stirred at 130°C, 96wt% of added poplar was dissolved in [C4mim]OAc, whereas 25.3wt% of poplar dissolved in [C4mim]Cl at the same reaction condition. Fourier transform infrared spectroscopy (FT-IR) and lignin content analysis revealed that poplar was partially delignified during the dissolution and regeneration processes. X-ray diffraction (XRD), thermal gravimetric analysis (TGA), and microscopy were used to characterize raw poplar sawdust, undissolved poplar, and regenerated wood from the poplar-ionic liquid solution. The direct acetylation of poplar-[C4mim]OAc solution using acetyl chloride was also performed in the absence of any organic solvent. FT-IR analysis of the resulting wood sample revealed the formation of partially delignified acetylated-poplar. 相似文献
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Trisiloxane ionic liquids with polyether groups (Si3pyCl-EO3) were synthesized via thiol-ene reaction between 1-methyl-1-[bis(vinyldimethylsiloxy)methyl]silylpropylpyrrolidinium chloride (Vi-Si3pyCl) and tri(ethylene glycol) methyl ether thiol. The aggregation behavior of the trisiloxane ionic liquids, Si3pyCl-EO3 and Vi-Si3pyCl, in aqueous solution was investigated using surface tension, electrical conductivity, dynamic light scattering, and transmission electron microscopy. The structures of trisiloxane ionic liquids can obviously influence their aggregation behavior. Vi-Si3pyCl has excellent surface activity (22.3 mN m−1). However, Si3pyCl-EO3 can only reduce the surface tension of water to 33.5 mN m−1. In comparison with Vi-Si3PyCl, Si3PyCl-EO3 has a bulkier hydrophobic group and a higher Αmin value (127.8 Å2) caused by the introduction of the tri(ethylene glycol) methyl ether groups by thiol-ene reaction. The micellization of Vi-Si3PyCl is entropy driven, while the aggregation process of Si3PyCl-EO3 in aqueous solution is enthalpy driven. 相似文献
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Yingjie Luo Yiwei Zhang Cimin Tao Hongfei Ni Xuesong Liu Yong Chen Yongjiang Wu Hang Song Tengfei Xu 《International journal of molecular sciences》2022,23(20)
Imidazolium-based ionic liquids are wildly used in natural product adsorption and purification. In this work, one typical polymeric ionic liquid (PIL) was synthesized by using L-proline as the anion, which exhibited excellent adsorption capacity toward tea polyphenol epigallocatechin gallate (EGCG). The adsorption conditions were optimized with the response surface method (RSM). Under the optimum conditions, the adsorption capacity of the PIL for EGCG can reach as high as 552 mg/g. Dynamics and isothermal research shows that the adsorption process of EGCG by the PIL particularly meets the quasi-second-order kinetic equation and monolayer adsorption mechanism. According to thermodynamic parameter analysis, the adsorption process is endothermic and spontaneous. The results of theoretical calculation by molecular docking also demonstrated the interaction mechanisms between EGCG and the ionic liquid. Considering the wide application of imidazolium-based ionic liquids in component adsorption and purification, the present study can not only be extended to other similar experimental mechanism validation, but also be representative for guiding the synthesis of PIL and optimization of adsorption conditions. 相似文献
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This study explores the use of COSMO-RS model and Peng-Robinson (PR) equation of state (EoS) to predict the solubility of carbon dioxide (CO2) in specific ionic liquids (ILs). COSMO-RS was employed to estimate of CO2 solubility at atmospheric pressure in eight imidazolium-based ILs resulting from the combination of ethyl, butyl, hexyl, and octyl-imidazolium cations with two anions: bis(trifluoromethylsulfonyl)imide ([Tf2N]) and Trifluoromethanesulfonate ([TFO]). The results indicated relatively acceptable qualitative consistency between the experimental and predicted values. The PR EoS was employed at high pressure by tuning the interaction parameters to fit the experimental data reported in the literature. The model demonstrated excellent accuracy in predicting the solubility of CO2 at pressure values less than the critical pressure of CO2; however, at higher pressures, the calculated solubility diverged from the experimental values. Furthermore, the type of anion and cation used in the IL affected the performance of the PR EoS. 相似文献
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Xiu-Jie Yang Peng Zhang Wenjiao Lv Ting Zhou Peng Li Mingwei Zhao 《Journal of surfactants and detergents》2019,22(3):515-523
Three kinds of imidazolium-based amino acid ionic liquid surfactants (AAILS), 1-tetradecyl-3-methylimidazolium L-aminopropionic acid salt ([C14mim][Ala]), 1-tetradecyl-3-methylimidazolium L-2-pyrrolidinecarboxylic acid salt ([C14mim][Pro]), and 1-tetradecyl-3-methylimidazolium L-aminohydrocinnamic acid salt ([C14mim][Phe]), were synthesized by employing natural amino acids as counterions. Their adsorption and self-aggregation behaviors in aqueous solution were investigated systematically by means of surface tension and electrical conductivity measurements. Surface tension results indicate that surface properties and micellization behavior of AAILS are significantly affected by counterions. The micellization of [C14mim][Pro] and [C14mim][Phe] is entropy-driven at low temperatures but enthalpy-driven at high temperatures, whereas [C14mim][Ala] is enthalpy-driven throughout the whole temperature range, owing to the variation in hydrophobicity and size of amino acid counterions. The surface activity of [C14mim][Phe] is superior to that of conventional imidazolium-based ionic liquid surfactants with the same hydrocarbon chain length, 1-tetradecyl-3-methylimidazolium bromide (C14mimBr), indicating that the aromatic counterion can promote the micellar formation process. 相似文献
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Sakhaeinia Hossein Zare-Neyestanak Elaheh Shokouhi Mohammad 《Theoretical Foundations of Chemical Engineering》2020,54(5):949-960
Theoretical Foundations of Chemical Engineering - In this study the solubility of Hydrogen Sulfide (H2S) in four ionic liquids: 1-Ethyl-3-methylimidazoliom Hexafluorophosphate [Emim][PF6],... 相似文献
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Mixed micellization behavior of dodecyl sulfate-based ionic liquids, i.e., 1-propyl-3-methylimidazolium dodecyl sulfate [C3mim][DS] and 1-hexyl-3-methylimidazolium dodecyl sulfate [C6mim][DS] with sodium dodecyl sulfate (SDS), is investigated at (298.15, 308.15, and 318.15) K in aqueous medium. For this, the conductometric measurements are carried out to evaluate the critical micelle concentrations (cmc ), ideal critical micelle concentration (cmc* ), degree of counterion dissociation (g ), thermodynamic parameters, micellar mole fraction of ionic liquids, and interaction parameter (β) of the mixed system based on the different proposed models given in the literature. Further surface tension measurements have been carried out to confirm the value of cmc obtained via a conductivity study for all the studied systems at 298.15 K. Other surface parameters, such as surface tension at cmc (γcmc ), surface pressure (ᴨcmc ), surface excess (Γmax ), and minimum area per molecule (Amin), have also been evaluated for both the systems. 相似文献
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Diana Fedunova Andrea Antosova Jozef Marek Vladimir Vanik Erna Demjen Zuzana Bednarikova Zuzana Gazova 《International journal of molecular sciences》2022,23(2)
Amyloid fibrils draw attention as potential novel biomaterials due to their high stability, strength, elasticity or resistance against degradation. Therefore, the controlled and fast fibrillization process is of great interest, which raises the demand for effective tools capable of regulating amyloid fibrillization. Ionic liquids (ILs) were identified as effective modulators of amyloid aggregation. The present work is focused on the study of the effect of 1-ethyl-3-methyl imidazolium-based ILs with kosmotropic anion acetate (EMIM-ac) and chaotropic cation tetrafluoroborate (EMIM-BF4) on the kinetics of lysozyme amyloid aggregation and morphology of formed fibrils using fluorescence and CD spectroscopy, differential scanning calorimetry, AFM with statistical image analysis and docking calculations. We have found that both ILs decrease the thermal stability of lysozyme and significantly accelerate amyloid fibrillization in a dose-dependent manner at concentrations of 0.5%, 1% and 5% (v/v) in conditions and time-frames when no fibrils are formed in ILs-free solvent. The effect of EMIM-BF4 is more prominent than EMIM-ac due to the different specific interactions of the anionic part with the protein surface. Although both ILs induced formation of amyloid fibrils with typical needle-like morphology, a higher variability of fibril morphology consisting of a different number of intertwining protofilaments was identified for EMIM-BF4. 相似文献
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The suspension rheology of hematite in the ionic liquid EcoengTM.212 was studied in detail and compared to the pure ionic liquid. This is the first report on the rheological behavior of suspensions in ionic liquids, and it is postulated that colloidal stability and rheology must be considered to understand these results, and to overcome limitations on the production of nanosized particles in industrial applications. Concentrated suspensions of particles in the nanometer range show non‐Newtonian flow behavior including shear thinning and shear thickening. These phenomena are mainly caused by particle‐particle interactions in the suspension, and control of these interactions is critical. The influences of temperature and solid concentration on flow behavior were shown for the pure liquid and the suspensions. It is seen that the ionic liquid follows the Arrhenius equation for non‐associating electrolytes. It is possible to shift all hematite suspension curves to a master curve according to the model of Gleißle and Baloch. Furthermore, the flow behavior of the suspensions can be modeled with the well‐known Herschel‐Bulkley plot. A 10 wt % suspension of Fe2O3 follows Newtonian behavior over the entire range, similar to the pure ionic liquid. It is believed that the ionic liquid has an influence on the stability of the particles, leading to a decrease of attractive particle‐particle forces. 相似文献