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1.
《分离科学与技术》2012,47(2):377-385
The potential of exploiting ionic liquids (ILs) for an ex situ solvent aromatic extraction technique is envisaged in this work, due to the serious proportions reached by this kind of contaminants associated with the industrial progress. 1-butyl-1-methylpyrrolidinium bis (trifluoromethylsulfonyl) imide, tetraalkyl ammonium sulfate, trihexyl (tetradecyl) phosphonium dicyanamide, 1-hexyl-3-methylimidazolium hexafluorophosphate, 1,3-dimethylimidazolium methyl sulfate, and 1-butyl-3-methylimidazolium methyl sulfate are proposed to efficiently extract benzene, toluene, and ethylbenzene at concentrations over the maximum allowable limit. The extraction procedure is completed with a washing and recycling step with the purpose of achieving a more competitive process.  相似文献   

2.
利用疏水性离子液体1-丁基-3-甲基咪唑六氟磷酸盐[Bmim][PF6]、1-丁基-3-乙基咪唑六氟磷酸盐[Beim][PF6]、1-丁基-3-甲基咪唑双三氟甲磺酰亚胺盐[Bmim][Tf2N]对水溶液中的9种芳香化合物进行萃取,以苯胺为代表对萃取工艺进行了优化,考察了乙醚、正丁醇等低极性溶剂对离子液体的再生情况. 结果表明,在室温下,当相比O/A=0.2、时间为10 min时,[Bmim][PF6]对苯胺的萃取率达87.2%,分配系数为34.1,效果明显高于甲苯、正辛醇等传统有机溶剂. 芳香化合物的分子结构对萃取有较大影响,萃取率及分配系数随溶质疏水性增加而增加. 用乙醚作为反萃剂效果较好,苯胺和离子液体的回收率分别为93.1%和95.2%,溶质及离子液体均能实现资源化回收利用.  相似文献   

3.
疏水性离子液体用于萃取酚类物质   总被引:32,自引:4,他引:32  
测定了苯酚、苯基酚、苯二酚等几种不同取代基的酚类物质在疏水性离子液体[bmim]PF6(1-丁基-3-甲基咪唑六氟磷酸盐)和[dmim]PF6(1-癸基-3-甲基咪唑六氟磷酸盐)与水两相中的分配系数. 实验结果表明,萃取过程很快可以达到平衡. 与传统有机溶剂相比,分配系数处在同一个数量级. 分配系数随温度升高而降低,离子液体对不同取代基的酚类萃取能力有很大差异,咪唑基团上取代烷基链的长度对不同酚类物质的分配系数有很大影响,因此可以通过调节离子液体结构使其适用于不同成分的含酚废水.  相似文献   

4.
近些年来,世界各国学者对离子液体的研究越来越多,随着对离子液体研究的深入,离子液体的应用逐渐渗透到各个领域中。主要介绍近年来离子液体在萃取有机物方面的应用进展。  相似文献   

5.
室温离子液体在萃取中的应用   总被引:6,自引:0,他引:6  
丁琪  乐长高 《化工时刊》2006,20(7):64-67
综述了室温离子液体在萃取中的应用研究,包括液—液萃取,液相微萃取,固相微萃取,超临界CO2萃取。  相似文献   

6.
《分离科学与技术》2012,47(7):1172-1177
In this work, ionic liquids/water distribution ratios (D) of azo dyes, including 1-(phenylazo)-2-naphthol, 1-(2-pyridylazo)-2-naphthol, 4-(nitrophenylazo)resorcinol, 4-(2-pyridylazo) resorcinol, and 2-(4-dimethylaminophenylazo) benzoic acid, have been determined experimentally. It was found that the D values are highly influenced by the pH of the water phase and the type of salts added. They increase with increasing alkyl chain length on the cations of the ionic liquids, and the anionic effect follows the order [BF4]? > [PF6]?. Possible extraction mechanism and selective separation of some azo dyes are also investigated. The results suggest that ionic liquids have potential applications in the removal and selective separation of azo dyes from water.  相似文献   

7.
The extractive removal of sulfur compounds (S-compounds) from Dongying and Liaohe diesel fuels with [BF4]^--based ionic liquids were systematically investigated. The results show that the absorption capacity of an ionic liquid for the S-compounds in diesel fuels relies on its structure and its size. In the case of the two examined diesel fuels, both elongating the cation tail length and increasing the mass ratio of ionic liquid/diesel fuel promote the desulfurization ability of the examined ionic liquids. The results also show that imidazolium-based ionic liquids display higher extraction efficiencies than pyridinium-based ionic liquids, presumably owing to the fact that the rings of the S-compounds are similar to the imidazolium head ring. With the 1 : 1 mass ratio of ionic liquid/diesel fuel, the rates of the first desulfurization of Dongying and Liaohe diesel fuels using [C8mim][BF4] amount to 29.96% and 39.76%, suggesting that [C8mim][BF4] is a promising extractant for desulfurization of these diesel fuels.  相似文献   

8.
本论文论述了以离子液体溴化1-丁基-3-甲基咪唑([BMIM]Br)水溶液作为提取剂,采用微波辅助技术从柠檬皮中提取果胶工艺研究.利用红外光谱和质谱对合成的[BMIM] Br进行了表征.系统研究了各个因素对果胶提取效果的影响,得到适宜的工艺条件为:[BMIM] Br浓度1.2 mol/L,液固比20 mL/g,萃取温度80℃,微波功率400W,萃取时间7 min.利用红外光谱对所得果胶进行了结构表征.  相似文献   

9.
离子液体在萃取分离中的应用   总被引:1,自引:0,他引:1  
在查阅了大量的国内外文献资料的基础上,介绍了近几年离子液体研究应用的进展。综述了离子液体在萃取分离过程中的应用,并展望了离子液体在分离方面的应用前景和发展方向。  相似文献   

10.
《分离科学与技术》2012,47(13):2075-2087
This work reports the prediction of selective extraction of cresol from aqueous solutions using ionic liquids (ILs) as the solvent. Judicious screening of various ILs was carried out for all the three forms of cresol (i.e., o-cresol, m-cresol, and p-cresol). A quantum chemical based theoretical model “conductor-like screening model for real solvents” (COSMO-RS) was used to predict the selectivity of cresol in aqueous medium at infinite dilution. A screening of 360 possible ILs from 15 cations and 24 anions was carried out to determine the best IL for the removal of cresol from water. Amongst the phosphonium and imidazolium based cations, trihexyl tetradecylphosphonium [THTDP] and 1-octyl-3-methylimidazolium [OMIM] gave the highest selectivity other than the anions bromide and chloride. The selectivities for different cresols followed the pattern: m-cresol > p-cresol > o-cresol. Similarly for pyridinium and quinolium based cations, 1-ethylpyridinium [EPY] and 1-octylquinolium [OQU] gave the highest selectivity. Amongst the two cations studied for pyrrolidinium based cations, 1-hexyl-1-methylpyrrolidinium [HMPL] was the best. Trihexyl tetradecylphosphonium salicyclate [THTDP][SAL] gave the highest selectivity of 662 amongst all the ILs screened.  相似文献   

11.
以TDI,MDI,IPDI,聚醚(N-220)和微晶纤维素为原料,在咪唑基离子液体氯化1-丁基-3-甲基咪唑中合成了系列纤维素基聚氨酯材料,并用FT-IR,TGA,XRD,SEM表征其结构与性能。TGA结果表明纤维素基聚氨酯材料具有良好的热稳定性能,以TDI,N-220,微晶纤维素为原料制备得到的材料热性能最优。XRD结果显示,聚氨酯链段的引入破坏了微晶纤维素的晶体结构,SEM照片显示,材料结构较为均一。  相似文献   

12.
《分离科学与技术》2012,47(4):828-841
Abstract

The separation of two noble organometallic catalysts from a homogeneous organic phase was investigated using liquid phase extraction with functionalized ionic liquids. Thirteen functionalized ionic liquids containing amino, hydroxy, thioether, carboxylic, or olefin functional groups were prepared by a standard neutralization method. The extractions of Jacobsen's catalyst and Wilkinson's catalyst were conducted using the functionalized ionic liquids as the extraction phase without adding any other metal complexing extractant. The distribution factors between the ionic liquid (IL) phase and toluene (organic solution phase) demonstrated that the functional groups in ILs exhibited moderate to high affinity with the metal complexes. The influence of the ionic liquid structure on the distribution factors was also investigated.  相似文献   

13.
论述了离子液体应用于燃料油萃取脱硫的发展历程,通过对比萃取脱硫、萃取耦合化学氧化脱硫、萃取联合催化氧化脱硫三种不同体系的脱硫机理与技术优势,探究了离子液体的萃取性、催化性、氧化性及其再生问题。阐述了离子液体在燃料油脱硫领域的发展趋势。  相似文献   

14.
《分离科学与技术》2012,47(17):2582-2588
Aromatic 1-butyl-3-methylimidazolium dicyanamide ([C4mim][N(CN)2]) and 1-ethyl-3-methylimidazolium dicyanamide ([C2mim][N(CN)2]) ionic liquids are tested for their performance in the extractive desulfurization of real FCC gasoline and diesel fuel. [C4mim][N(CN)2] has proven to be more effective than [C2mim][N(CN)2] in removing sulfur from fuels and was thus selected to undergo a series of further tests. A competitive desulfurization efficiency of nearly 40% and 30% was realized with [C4mim][N(CN)2] for diesel fuel and gasoline, respectively, in a single extraction at <1 h, 25°C, and 1:1(w/w)IL:fuel. The influence of IL:fuel mass ratio, temperature, and multiple extractions on S-extraction efficiency is investigated, and the result tends to favor large-scale industrial application. This high efficiency obtained at low temperature, together with the insensitivity of the Nernst partition coefficient on desulfurization efficiency, is industrially favorable because not much energy and cost are required. The influence of mass ratios is not obvious, but to some degree, the Nernst partition coefficients depend on the mass ratio, suggesting that this extraction is not a completely physically-determined extraction. This work offers a significant contribution to the production of clean oils by extraction with ionic liquids.  相似文献   

15.
离子液体是在室温下为液体、具有离子特性的新型绿色溶剂,作为一类环境友好型的反应介质,在诸多领域有其独特的性质.综述了普通离子液体和功能化离子液体的合成研究进展,并对其前景进行了展望.  相似文献   

16.
离子液体在萃取分离中的应用   总被引:1,自引:0,他引:1  
室温离子液体是由正负离子组成的室温为液体的熔融盐,因其具有极低的蒸汽压、可设计性和特殊的选择溶解能力等独特的性质,使得其在萃取分离有机物及金属离子、液相微萃取和汽油柴油中脱硫及碱性氮化物等领域都有着广泛应用。综述了离子液体在萃取分离上的应用进展。  相似文献   

17.
Ionic liquid based, microwave-assisted extraction (ILMAE) was successfully applied to the extraction of proanthocyanidins from Larix gmelini bark. In this work, in order to evaluate the performance of ionic liquids in the microwave-assisted extraction process, a series of 1-alkyl-3-methylimidazolium ionic liquids with different cations and anions were evaluated for extraction yield, and 1-butyl-3-methylimidazolium bromide was selected as the optimal solvent. In addition, the ILMAE procedure for the proanthocyanidins was optimized and compared with other conventional extraction techniques. Under the optimized conditions, satisfactory extraction yield of the proanthocyanidins was obtained. Relative to other methods, the proposed approach provided higher extraction yield and lower energy consumption. The Larix gmelini bark samples before and after extraction were analyzed by Thermal gravimetric analysis, Fourier-transform infrared spectroscopy and characterized by scanning electron microscopy. The results showed that the ILMAE method is a simple and efficient technique for sample preparation.  相似文献   

18.
A new kind of hydrophobic ionic liquids [1-alkyl-3-(1-carboxylpropyl)im][PF6] has been synthesized,and their extraction properties for Y(III) in the nitric acid medium was also investigated.The effects of extractant concentration,equilibrium pH of aqueous phase,salt concentration,temperature etc.were discussed.The results show that this kind of Task-Specific Ionic Liquid(TSIL) needs to be saponified before being used for the Y(III) ex-traction,and the extraction is acid dependent,and the extraction efficiency increases with the aqueous phase acidity decreasing.Furthermore,the loaded organic phase is easy to be stripped;more than 95% Y(III) could be stripped from the loaded organic phase when the stripping acidity is higher than 0.07 mol?L?1.The slope analysis technique is used to investigate the extraction mechanism,and a possible cation-exchange extraction mechanism is proposed in the present extraction system.  相似文献   

19.
《分离科学与技术》2012,47(11):1641-1646
In this paper, a series of ionic liquids (ILs) contains cholinium as cations were prepared. These ILs were used as extractants to separate some model drug molecules. The partition coefficients of these drug molecules between ILs and aqueous solutions were determined. Furthermore, the influence of different extraction parameters was investigated: volume ratio, equilibrium time, pH values, temperature, and ILs structure. It is shown that these ILs are highly effective materials for the extraction of drug molecules. The results imply that these ILs may have potential in drug extraction or separation as a new type of media.  相似文献   

20.
Ionic liquids, low temperature molten salts, have various advantages manifesting themselves as durable and environmentally friendly solvents. Their application is expanding into various fields including hydrometallurgy due to their unique properties such as non-volatility, inflammability, low toxicity, good ionic conductivity, and wide electrochemical potential window. This paper reviews previous literatures and our recent results adopting ionic liquids in extraction, synthesis and processing of metals with an emphasis on the electrolysis of active/light, rare earth, and platinum group metals. Because the research and development of ionic liquids in this area are still emerging, various, more fundamental approaches are expected to popularize ionic liquids in the metal manufacturing industry.  相似文献   

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