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1.
Permeabilities and selectivities of gases such as carbon dioxide (CO2), sulfur dioxide (SO2), nitrogen (N2) and methane (CH4) in six imidazolium-based ionic liquids ([emim][BF4], [bmim][BF4], [bmim][PF6], [hmim][BF4], [bmim][Tf2N] and [emim][CF3SO3]) supported on polyethersulfone microfiltration membranes are investigated in a single gas feed system using nitrogen as the environment and reference component at temperature from 25 to 45ºC and pressure of N2 from 100 to 400 kPa. It is found that SO2 has the highest permeability in the tested supported ionic liquid membranes, being an order of magnitude higher than that of CO2, and about 2 to 3 orders of magnitude larger than those of N2 and CH4. The observed selectivity of SO2 over the two ordinary gas components is also striking. It is shown experimentally that the dissolution and transport of gas components in the supported ionic liq-uid membranes, as well as the nature of ionic liquids play important roles in the gas permeation. A nonlinear in-crease of permeation rate with temperature and operation pressure is also observed for all sample gases. By considering the factors that influence the permeabilities and selectivities of CO2 and SO2, it is expected to develop an optimal supported ionic liquid membrane technology for the isolation of acidic gases in the near future.  相似文献   

2.
The density, viscosity, refractive index, heat capacity, heat of dilution, ionic conductivity, and electrochemical stability of 1-butyl-3-methylimidazolium bromide ([bmim][Br]), 1-butyl-3-methylimidazolium iodide ([bmim][I]), and 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]) were measured at room temperature or over a temperature range of 293.2 to 323.2 K. The density and refractive index values of [bmim][I] appeared to be the highest among three ionic liquids (ILs). However, the experimental viscosity values of [bmim][Br] were higher than those of [bmim][BF4], while the heat capacities and heats of dilution of [bmim][BF4] were higher than those of [bmim][Br]. The cyclic voltammogram of [bmim][br] and [bmim][BF4] indicated electrochemical windows in the stability range from 2.7 V of [bmim][[Br] to 4.7 V of [bmim][BF4].  相似文献   

3.
以1-甲基咪唑和氯化苄为原料合成中间体氯化1-苄基-3-甲基咪唑([BzMim]Cl),而后与氟硼酸钠交换阴离子合成了一种新的离子液体[BzMim][BF4],并考察了该离子液体催化甲苯与盐酸和聚甲醛的氯甲基化反应的催化活性和选择性。实验结果表明,[BzMim][BF4]能够催化以浓盐酸为原料的氯甲基化反应,目标产物甲基苄基氯的产率与文献报道以离子液体C12mimBr催化干燥氯化氢为原料的相仿;对同为浓盐酸原料的氯甲基化反应,其单氯甲基化选择性远高于文献报道的以离子液体[emim]BF4为催化剂的35%;当[BzMim][BF4]与甲苯的摩尔比为0.3,多聚甲醛(PF)与甲苯的摩尔比为1.3,浓盐酸与甲苯的摩尔比为7.5,80 oC下反应8 h时,目标产物甲基苄基氯的产率达到88.5%,单氯甲基化选择性高于99%。  相似文献   

4.
A support vector machine (SVM) model is presented concerning accurate prediction of the surface tension of the complex mixtures of ionic liquids (ILs)–amines–water using the most important types of amines employed in the gas sweetening plants, such as monoethanolamine, diethanolamine, and methyldiethanolamine. Different ILs, such as [bmim] [BF4], [bmim] [DCA], [mmim] [dmp], [emim] [dep], [bmim] [BF4], [bmim] [Br], [bmim] [BF4], and [bmim] [Br], are considered in the presented model. The effects of most important influencing parameters, such as temperature and mass fraction of amines and ILs, on the surface tension of the aqueous mixtures of ILs and amines are well represented. A comparison of the presented model and the most important models reveals that the suggested SVM model has better performance in terms of accuracy and generalizability. The percentage average absolute deviation between the predicted and experimental surface tensions is about 0.44% suggesting the superiority of the presented model over wide ranges of temperatures and species concentrations.  相似文献   

5.
梁卫东  李海风  张硕 《精细化工》2012,29(1):1-5,19
以三乙胺和苄氯为原料,通过中间体氯化苄基三乙胺盐([Nbz222]Cl)的阴离子交换反应合成了5种目标产物:苄基三乙胺四氟硼酸盐([Nbz222]BF4),苄基三乙胺六氟磷酸盐([Nbz222]PF6),苄基三乙胺硫酸氢盐([Nbz222]HSO4),苄基三乙胺磷酸二氢盐([Nbz222]H2PO4)和苄基三乙胺咪唑盐([Nbz222]Im),产物的结构通过FTIR、1HNMR、13CNMR、ESI-MS、元素分析得以确认。除[Nbz222]PF6之外,其余4种目标产物的熔点均低于100℃。热分析表明,目标离子液体的热稳定性顺序为:[Nbz222]HSO4>[Nbz222]BF4>[Nbz222]Im>[Nbz222]H2PO4,其中[Nbz222]HSO4具有较好的热稳定性,热分解温度在260℃左右。目标离子液体均有一定的吸水性并在极性溶剂中有较好的溶解性。  相似文献   

6.
开发易制备、价格便宜、面向SO2气体高效分离的离子液体(ILs),是当前ILs从实验探索迈向工业应用的难点与重大挑战。合成了不同摩尔比(3∶1、2∶1、1∶1、1∶2和1∶3)的1-乙基-3-甲基咪唑氯盐([Emim][Cl])和1-乙基-3-甲基咪唑乙酸盐([Emim][OAc])的离子液体混合物[Emim][Cl]x[OAc]1-x, 在测定其密度、黏度、热稳定性等基本物性数据的基础上,研究了[Emim][Cl]x[OAc]1-x混合物在不同温度和SO2分压下的SO2吸收能力。结果表明,[Emim][Cl]x[OAc]1-x能够有效地捕获SO2。[Emim][Cl]与[Emim][OAc]之间存在协同促进作用,有利于实现SO2高效吸收。[Emim][Cl]0.33[OAc]0.66混合液在1.0和0.2 atm(1 atm=101325 Pa)下捕获SO2量分别为(1.34±0.08)和(0.74±0.05) g/g,与现有结果相比,混合物在SO2捕获方面有明显优势。此外,这些离子液体混合物对二氧化硫的吸收和解吸具有良好的可逆性。  相似文献   

7.
分析了R161/[hmim][Tf2N]、R32/[emim][Tf2N]、R290/[emim][BF4]三种工质对的热力学性能;采用NRTL模型对制冷剂/离子液体的汽液相平衡数据进行了关联;探讨了发生器出口温度、蒸发器出口温度及吸收温度对循环比、COP及?效率的影响。R32/[emim][Tf2N]和R161/[hmim][Tf2N]的COP相近,R290/[emim][BF4]的COP最小;在蒸发温度、吸收温度分别是5、25℃时,R32/[emim][Tf2N]系统的COP随着发生温度的变化可达到0.59以上,R290/[emim][BF4]的COP低于0.1;降低吸收温度可以扩大循环的可行温度,提高COP;蒸发温度为5℃,吸收温度从30℃降低到25℃,COP可提高1.4倍以上。  相似文献   

8.
The self-metathesis of methyl oleate and methyl ricinoleate was carried out in the presence of ruthenium alkylidene catalysts 1-4 in [bmim] and [bdmim][X] type ionic liquids (RTILs) (X = PF(6) (-), BF(4) (-) and NTf(2) (-)) using the gas chromatographic technique. Best catalytic performance was obtained in [bdmim][X] type ionic liquids when compared with [bmim][X] type ionic liquids. Catalyst recycling studies were also carried out in the room temperature ionic liquids (RTILs) with catalysts 1-4 in order to explore their possible industrial application.  相似文献   

9.
采用超临界CO2萃取方法得到了高纯度的离子液体[bmim]PF6、[bmim]BF4 和[bupy]BF4。用反相键合相高效液相色谱法(HPLC)测定了三种离子液体中萘、菲、联苯、二苯并噻吩(DBT)和二苯基二硫醚在280~340K的溶解度,分别用两参数和三参数的NRTL方程关联了测得的溶解度数据。溶解度计算值与实验值的相对平均偏差在3.86~9.94%之间。显然,可以用NRTL方程描述这些固体物质与离子液体的固液相平衡。同样条件下,测定了乙苯—[bmim]PF6、十二烷基苯—[bmim]PF6 液液相平衡数据。前者的规律也可以用NRTL方程描述,两相溶解度计算值与实验值的平均偏差分别是10.20、3.37%。  相似文献   

10.
Two bi-part combined models containing reaction equilibrium thermodynamic model and an equation of state (EoS) including cubic plus association (CPA) or modified Soave-Redlich-Kwong (SRK), were employed to correlate H2S solubility in ionic liquids [emim][Lac], [bmim][Ac] and [emim][Pro]. RETM and CPA/mSRK are responsible for chemical and phase equilibria calculations, respectively. The RETM defines a complex formation reaction between an H2S and two IL molecules into the liquid phase so that a complex in the form of H2S(IL)2 is probable to produce. On the other side, CPA/mSRK EoSs perform phase equilibria computations to find pressure and vapor phase concentrations. In the case of CPA, both of H2S and the ionic liquids were considered as self-associating components which pursue 4C and 2B schemes, respectively. This model computes the pure IL parameters using experimental density data. In this work, critical properties were estimated through the modified Lydersen-Joback-Reid method, Eotvos and Guggenheim relations. Afterward, the binary systems were investigated by applying RETM. CPA presents average absolute deviations (AADs) equal to 2.41%, 13.42% and 3.52% for [emim][Lac], [bmim][Ac], and [emim][Pro], respectively. Moreover, the AADs obtained by mSRK are 3.75%, 5.07%, and 6.06%, respectively. As it is evident from the results, the combination of RETM with both CPA and mSRK EoSs will result in good correlation accuracy.  相似文献   

11.
Vapor pressures were measured for acetonitrile+1-butyl-3-methylimidazolium chloride ([C4mim][Cl]),+1-butyl-3-methylimidazolium tetrafluoroborate ([C4mim][BF4]) and+1-hexyl-3-methylimidazolium chloride ([C6mim][Cl]) at temperatures of 313 to 353 K by a quasi-static method. The experimental data for the binary sys-tems were correlated by the non-random two liquid (NRTL) equation with an average absolute relative deviation (AARD) of within 1.84%. The results indicate that the three ionic liquids (ILs) can result in a negative deviation from the Raoult's law for the binary solutions containing acetonitrile, and the affinity between ILs and acetonitrile mole-cules fol ows the order [C4mim][BF4]+acetonitrile N [C4mim][Cl]+acetonitrile N [C6mim][Cl]+acetonitrile.  相似文献   

12.
王松  徐君臣  银建中 《当代化工》2012,(10):1090-1093
为研究SO2对咪唑类普通离子液体输运特性、体积的影响,本文通过分子动力学方法模拟了293.15K时,常压下[bmim][PFs]和[bmim][BF4]与soz的?昆合物。结果表明,咪唑类普通离子液体的扩散系数随气体溶质摩尔分数的增加而增大,粘度则相应减小。吸收SO2对离子液体体积的影响极小。混合物摩尔体积随SO2摩尔分数增加呈直线下降。  相似文献   

13.
以鸡蛋清溶菌酶为模型蛋白,采用冷却结晶法结晶以及浊度法测定酶活性,研究了分别添加4种亲水性离子液体(1-丁基-3-甲基咪唑四氟硼酸盐([C4mim]BF4)、1-丁基-3-甲基咪唑氯盐([C4mim]Cl)、1-丁基-3-甲基咪唑溴盐([C4mim]Br)和1,3-二甲基咪唑碘化物([dmim]I))条件下溶菌酶晶体形态和晶体活性的变化。利用光学显微镜对溶菌酶结晶过程的晶体形态进行分析,结果表明添加离子液体会影响溶菌酶的晶体形态和尺寸。离子液体[C4mim]BF4介导的溶菌酶形成棒状晶体。与未添加离子液体相比,[C4mim]Cl和[C4mim]Br均未改变溶菌酶晶体形态,均呈块状晶体,但[C4mim]Cl和[C4mim]Br促进溶菌酶晶体生长,晶体尺度均增加。而添加[dmim]I,溶菌酶呈现针状晶体。采用浊度法测定溶菌酶晶体活性,结果表明不同的离子液体对溶菌酶晶体的活性...  相似文献   

14.
毛信表  刘莹  陈达  陈赵扬  马淳安 《化工学报》2017,68(5):2027-2034
以2-溴乙胺氢溴酸和N-甲基咪唑盐为原料合成了氨基功能化离子液体1-(2-胺乙基)-3-甲基咪唑溴盐([NH2-emim]Br),用1H NMR和IR对所制备的离子液体进行了表征,测得25℃下[NH2-emim]Br的黏度26.691 Pa·s、电导率0.1130 mS·cm-1,CO2的溶解饱和度82%(摩尔分数),将不同含量的[NH2-emim]Br与[Emim]BF4、[Bmim]BF4、[Bmim]PF6组成二元复合离子液体,并用于CO2电化学还原研究,循环伏安研究表明,CO2在[NH2-emim]Br(0.5%)-[Bmim]BF4复合离子液体中的还原峰电位较[Bmim]BF4正移0.4 V,还原峰电流增大9倍,黏度降低为0.08227 Pa·s,电导率增大至1.317 mS·cm-1,是一种较好的CO2电化学还原离子液体体系。  相似文献   

15.
Preparation of biodiesel from waste oils containing 72% of free fatty acids catalyzed by a novel Brφnsted addic ionicliquid 1-sulfobutyl-3-methylimidazolium hydrosulfate ([BHSO3MIM][HSO4]) was systematically investigated.Theoptimum molar ratio of methanol to waste oils,catalyst amount,reaction temperature and reaction time were 8/1,10% (based on the mass of waste oils),140 ℃ and 6 h,respectively,under which the obtained yield of biodieselreached 94.9%.Also,[BHSO3MIM][HSO4] as a catalyst still retained around 97% of its original catalytic activityafter successive re-use of 5 batches (6 h per batch),showing the excellent operational stability.Moreover,the acid-ic IL [BHSO3MIM][HSO4] was able to efficiently catalyze conversions of waste oils with different amounts of FFAs(free fatty acids) into biodiesel,and showed tremendous application potential.Therefore,an efficient and environ-mentally friendly catalyst is provided for the synthesis of biodiesel from waste oils with high acid value.  相似文献   

16.
Since most ionic liquids (ILs) decompose before reaching their critical state, the experimental measurement of their critical properties are not possible. In this study, the critical temperatures, critical pressures and acentric factors of ten commonly investigated ILs were determined by making an optimum fit of the calculated vapor-liquid equilibrium data of binary mixtures of CO2+IL to the experimental values found in literature. For this purpose, the Peng-Robinson equation of state (PR EoS) and the differential evolution optimization method were used. The ILs considered were 1-ethyl-3-methylimidazolium hexafluorophosphate ([emim][PF6]), 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([emim][Tf2N]), 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]), 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]), 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([bmim][Tf2N]), 1-hexyl-3-methylimidazolium tetrafluoroborate ([hmim][BF4]), 1-hexyl-3-methylimidazolium hexafluorophosphate ([hmim][PF6]), 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([hmim][Tf2N]), 1-octyl-3-methylimidazolium tetrafluoroborate ([omim][BF4]) and 1-octyl-3-methylimidazolium hexafluorophosphate ([omim][PF6]). To evaluate the ability of the determined parameters in predicting the phase behavior of systems other than the systems that were used for parameter optimization, both sets of parameters obtained in this work and that of Valderrama et al. were used to predict bubble-point pressures of CHF3+[bmim][PF6] (by using the PR EoS and the Soave-Redlich-Kwong equation of state. The bubble-point pressures of CO2+IL systems optimized in this study by the PR EoS were also determined using the Soave-Redlich-Kwong equation of state (SRK EoS). In addition, liquid densities of pure ILs were predicted using a generalized correlation proposed by Valderrama and Abu-Shark. In all cases, the various predicted properties of these ten ILs, were in better agreement with the experimental data, using the critical properties and acentric factor obtained in this study, compared to the values suggested by Valderrama et al.  相似文献   

17.
Molecular dynamics simulation with an all-atom force field has been carded out on the two binary sys- tems of [bmim][PF6]-CO2 and [bmim][NO3]-CO2 to study the transport properties, volume expansion and micro- structures. It was found that addition of CO2 in the liquid phase can greatly decrease the viscosity of ionic liquids (ILs) and increase their diffusion coefficient obviously. Furthermore, the volume expansion of ionic liquids was found to increase with the increase of the mole fraction of CO2 in the liquid phase but less than 35% for the two simulated systems, which had a significant difference with CO2 expanded organic solvents. The main reason was that there were some void spaces inter and intra the molecules of ionic liquids. Finally, site to site radial distribution functions and corresponding number integrals were investigated and it was found that the change of microstructures of ILs bv addition CO2 had a great influence on the orooerties of ILs.  相似文献   

18.
Vapor pressures were measured for acetonitrile+1-butyl-3-methylimidazolium chloride ([C4mim][Cl]),+1-butyl-3-methylimidazolium tetrafluoroborate ([C4mim][BF4]) and+1-hexyl-3-methylimidazolium chloride ...  相似文献   

19.
The alkylation of toluene with 1,3-pentadiene to produce pentyltoluene was carded out to obtain 2,6-dimethylnaphalene, which is an important intermediate during the production of 2,6-naphthalene dicarboxylic acid. Based on our previous work using anhydrous AlCl3 as catalyst, [bupy]BF4-AlCl3 ionic liquids were employed to catalyze the reaction of 1,3-pentadiene with toluene. The experimental results show that [bupy]BF4-AlCl3 ionic liquids are suitable for the reaction especially when the molar ratio of AlCl3 to [bupy]BF4 is 1.75 : 1, and the reaction could proceed at the temperature as low as 0℃. It could be as active as pure AlCl3, but much more environmentally friendly.  相似文献   

20.
Thiswork provides amethod to explore the transport property of the electrolyte aqueous solutionswith one or two ionic liquids, especially focus on their electrical conductivity. The conductivities were measured for the ternary systems NaCl–[C6mim][Cl] (1-hexyl-3-methylimidazolium chloride)–H2O, [C6mim][BF4]–[C6mim][Cl]–H2O, NaNO3–[C6mim][BF4](1-hexyl-3-methylimidazolium tetrafluoroborate)–H2O, and [C4mim][BF4] (1-butyl-3- methylimidazolium tetrafluoroborate)–[C6mim][BF4]–H2O, and their binary subsystems NaNO3–H2O, NaCl–H2O, [C6mim][BF4]–H2O, [C6mim][Cl]–H2O, and [C4mim][BF4]–H2O, respectively. The conductivities of the ternary systems were also determined using generalized Young's rule and semi-ideal solution theory in terms of the data of their binary solutions. The comparison showed that the two simple equations provide good predictions for conductivity of mixed electrolyte solutions and the mixed ionic liquid solutions based on the conductivity of their binary subsystems.  相似文献   

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