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1.
咪唑基离子液体的物理化学性质估算及预测(英文)   总被引:1,自引:0,他引:1  
根据经验和半经验方程及空隙模型理论,可以估算及预测离子液体在298.15K的物理化学性质.本文讨论了离子液体的分子体积,密度,标准熵,晶格能,表面张力,等张比容,摩尔蒸发焓,空隙体积,空隙率和热膨胀系数.通过实验测得的三种离子液体1-乙基-3-甲基咪唑硫酸乙酯([C2mim][EtSO4)]),1-丁基-3-甲基咪唑硫酸辛酯([C4mim][OcSO4])和1-乙基-3-甲基咪唑双三氟甲磺酰亚胺盐([C2mim][NTf2])的密度和表面张力估算了它们的其它物理化学性质.由这三种离子液体的分子体积及等张比容预测了同系列中其它离子液体[Cnmim][EtSO4],[Cnmim][OcSO4]和[Cnmim][NTf2](n=1-6)的分子体积及等张比容,由此计算出它们的密度及表面张力.进而预测了它们的物理化学性质.将预测的离子液体[C4mim][NTf2]和[C2mim][OcSO4]的密度值与文献报导的实验值进行比较,其偏差在实验误差范围内.最后,将由Kabo经验方程计算的七个离子液体[C2mim][EtSO4]、[C4mim][OcSO4]、[C2mim][NTf2]、[C4mim][NTf2]、丁基三甲基铵双三氟甲磺酰亚胺盐([N4111][NTf2])、甲基三辛基铵双三氟甲磺酰亚胺盐([N8881][NTf2])和1-辛基-3-甲基吡啶四氟硼酸盐([m3opy][BF4])的摩尔蒸发焓与由Verevkin简单规则预测的摩尔蒸发焓进行比较,发现两者符合很好.因此,在缺乏密度和表面张力实验数据的情况下,可以用Verevkin简单规则来预测离子液体的摩尔蒸发焓.  相似文献   

2.
开发了一个以钯/碳为催化剂高效绿色催化Suzuki反应制备联苯类化合物的新方法.该体系以环境友好的聚乙二醇400的水溶液为反应溶剂,加入离子液体1-甲基-3-丁基咪唑双三氟甲磺酰亚胺盐,可高效催化溴代芳烃与芳基硼酸的Suzuki交叉偶联反应,并且催化剂可以循环利用4次而催化效率没有明显降低.  相似文献   

3.
用微波辐射法,合成了5个含有机膦氧基团的离子液体:1-丙基-3-(3-二苯基氧膦基)丙基咪唑双(三氟甲基磺酰基)亚胺盐([PImC3P(O)Ph2][Tf2N])、1-己基-3-(3-二苯基氧膦基)丙基咪唑双(三氟甲基磺酰基)亚胺盐([HImC3P(O)Ph2][Tf2N])、1-丙基-3-(3-苯基乙氧基氧膦基)丙基咪唑双(三氟甲基磺酰基)亚胺盐([PImC3P(O)Ph(OEt)][Tf2N])、1-己基-3-(3-苯基乙氧基氧膦基)丙基咪唑双(三氟甲基磺酰基)亚胺盐([HImC3P(O)Ph(OEt)][Tf2N])和(3-苯基乙氧基氧膦基)丙基三乙胺双(三氟甲基磺酰基)亚胺盐([TENC3P(O)Ph(OEt)][Tf2N])。 用31P NMR、1H NMR、13C NMR、MS及FT-IR对产物结构进行了表征。 研究了这类离子液体对稀土Nd(III)的萃取性能。 结果表明,这类功能化离子液体可作为单一组分萃取稀土而无需加入有机稀释剂,离子液体结构对萃取效率影响很大,相同条件下季铵盐型结构的离子液体[TENC3P(O)Ph(OEt)][Tf2N]对稀土Nd(Ⅲ)的萃取效率最高。 稀土溶液pH值对萃取效率影响显著,近中性条件下(pH=6.63),对稀土Nd(Ⅲ)的萃取率最高。 用pH=1.00的盐酸溶液可以较好的从离子液体相反萃Nd(Ⅲ),反萃率可达94%。  相似文献   

4.
采用反气相色谱技术(IGC),研究了1-乙基-3-甲基咪唑三氟甲磺酸盐(EMIMOTF)、1-丁基-3-甲基咪唑三氟甲磺酸盐(BMIMOTF)、1-己基-3-甲基咪唑三氟甲磺酸盐(HMIMOTF)、1-辛基-3-甲基咪唑三氟甲磺酸盐(OMIMOTF)4种离子液体(ILs)表面的物理化学性质。结果表明,4种ILs色散分量均随着温度升高而降低,表面自由能变化与ILs色散分量相一致。4种ILs Lewis酸碱性均呈现Lewis两性偏碱性,Kb/Ka分别为3.857、3.716、3.632和3.332。  相似文献   

5.
卢凯  刘伟  齐美玲  李言  傅若农 《色谱》2010,28(8):731-736
采用静态法将合成的端羟基单阳离子咪唑离子液体1-(6-羟己基)-3-丁基咪唑二(三氟甲基)磺酰亚胺盐(HHBIM-NTf2)和1-(8-羟辛基)-3-丁基咪唑二(三氟甲基)磺酰亚胺盐(HOBIM-NTf2)作为固定相制备离子液体毛细管气相色谱柱。采用Grob试剂、混合醇样品和芳香族异构体混合物对固定相色谱选择性进行了考察,Grob试剂和混合醇组分产生的尖锐、对称的色谱峰形及异构体混合物组分达到基线分离的结果均表明端羟基离子液体固定相具有良好的色谱选择性。HHBIM-NTf2柱和HOBIM-NTf2柱经250 ℃老化8 h后对异构体混合物的分离能力没有明显下降,而HHBIM-NTf2柱经300 ℃老化后仍有理想的异构体选择性,表明端羟基离子液体固定相具有理想的热稳定性。本结果为进一步改善单阳离子型咪唑离子液体固定相的色谱性能提供了有效途径。  相似文献   

6.
许超  王玲  骆浩  邹定兵  应桃开 《无机化学学报》2007,23(11):1941-1946
以1-正丁基-3-甲基咪唑溴盐离子液体([BMIM]Br)/水体系为反应介质,利用简便的液相沉淀法在室温下合成了钼酸钙(CaMoO4)中空微球体材料。分别利用X-射线粉末衍射(XRD)、场发射扫描电子显微镜(SEM)以及透射电子显微镜(TEM)对产品的相结构及形貌进行表征,发现产品为空心结构的白钨矿型微米级球体,并且该CaMoO4微球体是由粒径为10~20 nm的纳米粒子聚集而成。利用紫外可见(UV-Vis)漫反射谱及室温光致发光(PL)谱测试了产品的光学性质。通过与纯水相、1-乙基-3-甲基咪唑溴盐离子液体([EMIM]Br)/水及1-正己基-3-甲基咪唑溴盐离子液体([HMIM]Br)/水等体系中所得产品的对比,证明了[BMIM]Br对产品的形貌及光学性能等具有重要影响,并对中空微球体形成的机理进行了讨论。  相似文献   

7.
合成了新型离子液体(ILs)1-烷基-3-羧甲基苯并三氮唑双三氟甲磺酰亚胺盐,并对其进行了表征.将其与双氧水组成催化氧化体系,考察了脱除模型油品中硫化物的效果.结果表明,以离子液体1-5基-3-羧甲基苯并三氮唑双三氟甲磺酰亚胺盐[C2O2BBTA][NTf2]为萃取/催化剂,设定n(H2O2)∶n(S)=2.5∶1,m(模型油)∶m(离子液体)=5∶1,在75℃下反应1 h后,模型油中二苯并噻吩(DBT)、苯并噻吩(BT)和4,6-二甲基二苯并噻吩(4,6-DMDBT)的脱硫率分别为98.3%,98.3%和96.6%.所合成离子液体重复使用10次,脱硫率无明显变化.该方法操作简单、反应条件温和,可以实现深度脱硫.  相似文献   

8.
合成并表征了一类新型离子液体1-烷基-3-羧甲基苯并咪唑双三氟甲磺酰亚胺盐,将其与双氧水组合用于脱除模型油中的硫化物.结果表明,当模型油与萃取/催化剂1-辛基-3-羧甲基苯并咪唑双三氟甲磺酰亚胺盐([C_2O_2OBIM][Tf2N])的质量比为5∶1,H_2O_2/S摩尔比为5∶1,于75℃反应1 h后,模型油中二苯并噻吩(DBT)脱硫率为98.8%;脱硫过程符合一级动力学方程,5种硫化物的脱硫速率大小顺序为二苯并噻吩(DBT)4,6-二甲基二苯并噻吩(4,6-DMDBT)苯并噻吩(BT)2,5-二甲基噻吩(2,5-DMT)噻吩(T),其中脱除DBT和BT的反应表观活化能分别为44.16和52.10 k J/mol.该离子液体循环再生使用14次,脱硫率无明显下降.该深度脱硫方法具有操作简便及条件温和的特点.  相似文献   

9.
设计合成了双齿有机膦功能化离子液体(PFIL):1,3-双-[3-(二苯基膦酰基)丙基]咪唑双(三氟甲基磺酰基)亚胺盐([BPh2P(O)C3Im][NTf2]),其结构经FT-IR,31P NMR,1H NMR,13C NMR和HRMS确认。研究了双齿离子液体和单齿离子液体1-丙基-3-(3-二苯基膦酰基)丙基咪唑双(三氟甲基磺酰基)亚胺盐([C3Ph2P(O)C3Im][NTf2])对钕的萃取行为。考察了萃取时间、初始水相p H值、离子液体浓度、盐析效应等因素对萃取过程的影响。结果表明:萃取过程很快达到平衡;在弱酸性下萃取效果最好;萃取效率随着离子液体的浓度增大而增大;双齿功能化离子液体的萃取效率明显优于单齿离子液体;PFIL离子液体萃取稀土可能是中性络合机制。  相似文献   

10.
采用活性亚结构拼接法,设计合成了系列新型含三氟甲基吡啶酰胺结构的N-氰基磺酰亚胺类衍生物,其结构经1H NMR、~(13)C NMR、~(19)F NMR和HRMS进行了表征.评估了它们对柑橘溃疡病菌(Xanthomonas axonopodis pv. citri)、烟草青枯病菌(Ralstoniasolanacearum)和水稻白叶枯病菌(Xanthomonasoryzaepv.oryzae)的杀菌活性及对小菜蛾(Plutella xylostella)的杀虫活性.结果表明,部分化合物表现出了良好的抗菌活性和中等的杀虫活性.其中,在200 mg/L质量浓度下,3-氯-(2-(N-氰基-S-(3,4-二氟苄基)磺酰亚胺酰基)乙基)-5-(三氟甲基)吡啶酰胺(G10)对柑橘溃疡病菌、烟草青枯病菌和水稻白叶枯病菌的抑制率分别为67%、53%和48%,3-氯-(2-(N-氰基-S-(2,5-二氟苄基)磺酰亚胺酰基)乙基)-5-(三氟甲基)吡啶酰胺(G17)对柑橘溃疡病菌的抗菌活性为69%,(2-(S-(2-溴-4-氟苄基)-N-氰基磺酰亚胺基)乙基)-3-氯-5-(三氟甲基)吡啶酰胺(G14)对水稻白叶枯病菌的抑制率为49%.在100 mg/L时,(2-(S-(4-溴-2-氟苄基)-N-氰基磺酰亚胺基)乙基)-3-氯-5-(三氟甲基)吡啶酰胺(G1)、3-氯-(2-(N-氰基-S-(3-氟苄基)磺酰亚胺基)乙基)-5-(三氟甲基)吡啶酰胺(G7)、3-氯-(2-(N-氰基-S-(2,4-二氟苄基)磺酰亚胺酰基)乙基)-5-(三氟甲基)吡啶酰胺(G8)和G10也有中等的杀菌活性,在测试浓度下,部分化合物的活性略高于对照药剂或与之相当.此外,在500mg/L时,化合物G10和3-氯-(2-(N-氰基-S-(4-异丙基苄基)磺酰亚胺基)乙基)-5-(三氟甲基)吡啶酰胺(G11)对小菜蛾的致死率分别为77%和70%.  相似文献   

11.
Three ionic liquids(ILs), namely, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-me- thylimidazolium bis[(trifluoromethyl)sulfonyl]imide and 1-ethyl-3-methylimidazolium bis[(trifluoromethyl)sul- fonyl]imide with the triisobutyl phosphate(TIBP) and kerosene system were respectively used to extract lithium ion from salt lake brine with a high concentration ratio of magnesium and lithium experimentally. Results indicate that the highest extraction selectivity for lithium was obtained with IL 1-ethyl-3-methylimidazolium bis[(trifluoromethyl)- sulfonyl]imide. The effects of solution pH and phase ratio R(O/A) on the extractive step and the influence of acid concentration of the stripping solution and R(O/A) on the back extraction step were also investigated systematically. The single-step extraction efficiency of lithium ion was 83.71% under the optimal extraction conditions, and the single-step back extraction efficiency was 85.61% with a 1.0 mol/L HCl in 1.0 mol/L NaCl medium as stripping agent at R(O/A)=2. The liquid-liquid extraction mechanism and the complex of the ligand with lithium were proposed.  相似文献   

12.
The electrochemical behaviour of nanoporous TiO(2) in a room temperature ionic liquid (RTIL), 1-ethyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)amide (EMITFSI), was investigated by cyclic voltammetry (CV) and impedance spectroscopy. Exponentially rising currents in voltammetry were attributed to the charging/discharging of electrons in the TiO(2) film and a charge transfer mechanism. The main features of the voltammetry and impedance followed the same trends in the ionic liquid as in other organic solvents and also in aqueous electrolytes. In the presence of lithium ions, the onset potential of the charge accumulation increased due to the change of the initial position of the TiO(2) conduction band. The results show that substitution of organic solvents contained in solar cells, supercapacitors or other electrochemical devices is in general feasible, though requires some adjustment in the electrolyte composition for optimal performance.  相似文献   

13.
Interfacial distribution of rare earth elements (REE) La, Ce, Pr, Nd, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y between aqueous solutions of their nitrates and solutions of the lariat crown ether 1,4,10,13-tetraoxa-7,16-diaza(diphenylphosphinylmethyl)cyclooctadecane in dichloroethane was studied in the presence of the ionic liquids 1-butyl-3-methylimidazolium hexafluorophosphate and 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide. The stoichiometry of extracted complexes was determined; the effect of HNO3 concentration in the aqueous phase and the nature of extractant and ionic liquid on the extraction efficiency of REE(III) was considered.  相似文献   

14.
Composite polymer electrolytes based on mixing soft-segment waterborne polyurethane(WPU)and 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide(BMImTFSI)have been prepared and characterized.The addition of BMImTFSI results in an increase of the ionic conductivity.At high BMImTFSI concentration(BMImTFSI/WPU=3 in weight ratio),the ionic conductivity reaches 4.27×10~(-3)S/cm at 30℃.These composite polymer electrolytes exhibit good thermal and electrochemical stability,which are high enough to be...  相似文献   

15.
The distribution of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Sc between aqueous solutions of their salts and solutions of 2-phosphorylphenoxy acid amides in dichloroethane containing an ionic liquid (1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide) have been studied. Metal ion extraction has been found to increase considerably in the presence of this ionic liquid in the organic phase. The stoichiometries of extractable complexes have been determined. The influence of aqueous HNO3 concentration and of the nature of extractant and ionic liquid on the efficiency of REE(III) and scandium(III) recovery to the organic phase has been considered.  相似文献   

16.
以苄基功能化的离子液体1-苄基-3-甲基咪唑双三氟甲烷磺酰亚胺(1-Benzyl-3-methylimidazolium bis [(trifluoromethyl)sulfonyl]imide,[BeMIM][Tf2 N])作为分散液-液微萃取的萃取剂,与高效液相色谱联用,用于环境水样中5种有机磷农药(辛硫磷、杀螟松、毒死蜱、甲拌磷和对硫磷)以及2种苯环化合物(氯化萘和蒽)的萃取与富集。并与其它离子液体([OMIM][Tf2 N])以及普通有机溶剂(CCl4和 C2 Cl4)的萃取效能进行了对比。萃取优化条件为:40μL [BeMIM][Tf2 N]作为萃取剂,1 mL 甲醇作为分散剂,离心时间5 min,样品溶液中不添加盐。在优化的条件下,本方法的线性关系良好(R2=0.9994~0.9998);对10,40和100μg/ L 不同添加浓度重复测定5次的日内和日间 RSD 分别为1.1%~4.3%和0.8%~4.8%,LOD 为0.01~1.0μg/ L (S/ N=3)。将本方法用于3种实际水样中目标分析物的测定,加标回收率和 RSD 分别为82.7%~118.3%和0.7%~5.6%。由于在咪唑环上引入了苄基基团,[BeMIM][Tf2 N]与目标分析物之间除存在疏水作用外,还存在π-π作用,故对目标物的萃取效率明显提高,富集倍数和回收率分别高达339和81.4%。测定了分析物在[BeMIM][Tf2 N]-DLLME 体系中的分配系数,对萃取机制进行初步探讨。  相似文献   

17.
Accurate data on transport properties such as viscosity are essential in plant and process design involving ionic liquids. In this study, we determined the absolute viscosity of the ionic liquid + water system at water mole fractions from 0 to 0.25 for three 1-alkyl-3-methylimidazolium ionic liquids: 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium bis(trifluoromethane sulfonyl)imide and 1-ethyl-3-methylimidazolium bis(trifluoromethane sulfonyl)imide. In each case, the excimer to monomer ratio for 1,m-bis(1-pyrenyl)alkanes (m= 3 or 10) was found to increase linearly with the mole fraction of water. Of the probes studied only PRODAN and rhodamine 6G, both of which have the ability to participate in hydrogen bonding, exhibited Perrin hydrodynamic behavior in the lower viscosity bis(trifluoromethane sulfonyl)imides. As a result, these probes allow for the extrapolation of the absolute viscosity of the ionic liquid mixture from the experimental fluorescence steady-state polarization values.  相似文献   

18.
Selective π-complexation capabilities of silver(I) and copper(I) ions can be effectively facilitated in ionic liquids. To understand the effects of environmental factors that influence the π-complexation of these metal ions with analytes, techniques that employ small volumes of ionic liquid that can be readily analyzed are desired. In this study, headspace single drop microextraction coupled with HPLC is used to investigate a diverse set of environmental factors on the metal ion-mediated complexation with aromatic compounds in ionic liquid media. Silver(I) and copper(I) bis[(trifluoromethyl)sulfonyl]imide salts were both studied by dissolving them in the 1-decyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide ionic liquid and employing the mixture as extraction media for aromatic compounds. Water and acetonitrile within the sample solution were observed to interfere with the complexation of silver(I) ions and aromatic compounds, while ethylene glycol and triethylene glycol did not. The temperature and extraction times were optimized to fully facilitate the π-complexation capabilities of metal ions in ionic liquid media. Partition coefficients between the sample headspace and metal ion were determined using a three-phase equilibria model. Although no discernable difference in analyte partitioning between the headspace and ionic liquid solvent was observed, analyte partition coefficients to silver(I) ion tended to be greater compared to copper(I) ion.  相似文献   

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制备了功能化离子液体1-丁腈-3-甲基咪唑双三氟甲基磺酸亚胺。在T为283.15-353.15 K温度范围内,测定了该功能化离子液体的密度、动力粘度、电导率及折光率。讨论了亚甲基的增减对该类功能化离子液体的密度、动力粘度、电导率及折光率等性质的影响,并与传统咪唑类、吡啶类离子液体物理化学性质的变化趋势进行了对比。通过经验方程计算了该功能化离子液体的热膨胀系数、分子体积、标准摩尔熵及晶格能等热力学性质参数。讨论了Vogel-Fulcher-Tamman (VFT)方程和Arrhenius方程的适用性,得出VFT方程适用于该功能化离子液体,而Arrhenius方程并不适用。有关研究对新型离子液体的合成及其工业化的应用具有十分重要的意义。  相似文献   

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