乙腈+[C4mim][Cl]、乙腈+[C4mim][BF4]、乙腈+[C6mim][Cl]的气液平衡测定与关联（英文）

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.     

离子液体对溶菌酶晶体形态和活性的影响

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...     

2,6-二甲氧基苯酚在1-丁基-3-甲基咪唑四氟硼酸盐水溶液中溶解行为的红外光谱分析

利用衰减全反射红外光谱(ATR-IR)和二维相关红外技术研究2, 6-二甲氧基苯酚(2, 6-DMP)在1-丁基-3-甲基咪唑四氟硼酸盐([C₄mim]BF₄)水溶液(离子液体摩尔分数x_IL=1.0～0.02)中的溶解行为。随着水量增大, 2, 6-DMP溶解度先增大而后急剧减小, 对应的x_IL阈值为0.1。2, 6-DMP与[C₄mim]BF₄之间存在强相互作用, 2, 6-DMP上的甲氧基是重要作用位点之一;当少量的水加入[C₄mim]BF₄(x_IL=0.1～1.0), 致密的离子簇结构被解离, 2, 6-DMP容易与[C₄mim]BF₄作用, 溶解度增大;随着大量水加入(0.02IL<0.1), 离子簇完全解离为大分子水簇包围的离子对, 憎水的2, 6-DMP与[C₄mim]BF₄作用困难, 溶解度减小。这种由于水量改变引起的[C₄mim]BF₄水溶液微观结构变化影响2, 6-DMP溶解行为。     

1-丁基-3-甲基咪唑氯盐离子液体水溶液对纤维素的作用

在温度90℃, 压力1 MPa条件下, 研究[C₄mim]Cl-水溶液对纤维素的溶解和结构变化的影响。在离子液体含量为60%～95%时, 无定形纤维素可以部分溶解, 并且加去离子水后有纤维素再生。经过[C₄mim]Cl-水溶液处理一段时间后, 微晶纤维素的晶型并没有发生改变, 但纤维素的结晶指数和晶粒尺寸的大小都有明显的变化, 纤维素的分子内和分子间氢键相对强度也有明显变化。离子液体含量不同对微晶纤维素的作用程度不同。     

Modified g-C3N4 derived from ionic liquid and urea for promoting visible-light photodegradation of organic pollutants

In this work, modified g-C₃N₄ was fabricated successfully by calcination of ionic liquid (IL) and urea. The addition of IL changed the polymerization mode of urea, induced the self-assembly of urea molecules, modified the morphological structure of the tightly packed g-C₃N₄, and extended the electron conjugation system. When using 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) as a modifier, the heteroatom Cl could be inserted into the g-C₃N₄ to optimize the electronic structure. The results of characterizations indicate that the unique structure of modified g-C₃N₄ has an expanded electron delocalization range, introduces an interlayer charge transmission channel, promotes the charge transmission, reduces the band gap, enhances the absorption of visible light, and inhibits electron-hole recombination. Modified g-C₃N₄ showed excellent photocatalytic performance for the degradation of rhodamine B and tetracycline. Furthermore, the effect of different anions in 1-butyl-3-methylimidazolium salts ([Bmim]Cl, [Bmim]Br, [Bmim][BF₄], and [Bmim][PF₆]) on the structure and function of g-C₃N₄ are discussed.     

含离子液体乙腈-正丙醇体系的等压汽液平衡

常压(101.3 kPa)下, 测定了如下体系的汽液平衡数据:乙腈-正丙醇-氯化1-苄基-3-甲基咪唑([BzMIM][Cl])、乙腈-正丙醇-溴化1-苄基-3-甲基咪唑([BzMIM][Br])、乙腈-正丙醇-溴化1-己基-3-甲基咪唑([HMIM][Br]), 考察了3种离子液体对乙腈-正丙醇体系相平衡行为的影响。实验结果表明, 3种离子液体都能够提高乙腈对正丙醇的相对挥发度, 3种离子液体提高相对挥发度的顺序为 [BzMIM][Cl] > [BzMIM][Br] > [HMIM][Br]。用NRTL模型对测得的汽液平衡数据进行了关联, 关联结果与实验结果具有良好的一致性。     

采用 UNIFAC 模型预测吸收式循环氨-离子液体工质对的气液相平衡简

On the basis of reported experimental vapor-liquid equilibrium （VLE） data of NH3-1-ethyl-3-methylimidazolium acetate （NH3-[Emim]Ac）, NH3-1-butyl-3-methylimidazolium tetrafluoroborate （NH3-[Bmim][BF4]）, NH3-1,3-dimethylimidazolium dimethyl phosphate （NH3-[Mmim]DMP） and NH3-1-ethyl-3-methylimidazolium ethylsulfate （NH3-[Emim]EtOSO3） binary systems, the interaction parameters of 14 new groups have been regressed by means of the UNIFAC model. To validate the reliability of the method, these parameters have been used to calculate the VLE data with the average relative deviation of pressures of less than 9.35%. The infinite dilution activity coefficient （ γ1∞ ） and the absorption potential （ φ1 ） are important evaluation criterions of the affinity between working pair species of the absorption cycle. The UNIFAC model is implemented to predict the values of and φ1 of t6 sets of NH3-ionic liquid （1L） systems. The work found that the φ1 gradually increases following the impact order： φ1（[Cnmim][BF4]）〈φ1（[Cnmim]EtOSO3）〈φ1（[Cnmim]DMP）〈φ1（[Cnmim]Ac） （n= 1, 2, 3, … ） at a given cation of IL species and constant temperature, and φ1（[Mmim]X）〈φ1（[Emim]X）〈φ1（[Pmim]X）〈 φ1（[Bmim]X）（X= Ac, [BF4], DMP or EtOSO3） at a given anion of IL species and constant temperature. Furthermore, the φ1 gradually increases with increasing temperature. Then, it could be concluded that the working pair NH3-[BmimlAc has the best potential research value relatively.     

纤维二糖在离子液体1-丁基-3-甲基咪唑氯盐中的结构动力学特性

开展分子动力学模拟探索不同压力条件下纤维素的基本结构单元--纤维二糖在离子液体1-丁基-3-甲基咪唑氯盐（[C₄mim]Cl）中的结构动力学特征。研究结果表明,高压环境使二糖分子内氢键网络结构瓦解,二糖与阴阳离子间相互作用增强,形成溶质-溶剂间氢键。借助空间分布函数得到常压及高压环境下二糖分子周围溶剂层分布特征,并通过径向分布函数定量考察了纤维二糖/离子液体体系分子间与分子内的氢键特征,为在化学键水平上认识纤维素在离子液体中溶解机制提供必要的理论基础。     

Physical and electrochemical properties of 1-butyl-3-methylimidazolium bromide, 1-butyl-3-methylimidazolium iodide,and 1-butyl-3-methylimidazolium tetrafluoroborate

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].     

Surface tension and viscosity of 1-butyl-3-methylimidazolium iodide and 1-butyl-3-methylimidazolium tetrafluoroborate, and solubility of lithium bromide+1-butyl-3-methylimidazolium bromide in water

The surface tension and viscosity of 1-butyl-3-methylimidazolium iodide ([bmim][I]) and 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF₄]) were measured over a temperature range of 298. 15 to 323.15 K. It was found that both the viscosity and surface tension decrease with increasing temperature and that the surface tension and viscosity values of [bmim][I] were higher than those of [bmim][BF₄]. Additionally, the solubility of lithium bromide (2)+1-butyl-3-methylimidazolium bromide ([bmim][Br]) (3) in water (1) was measured at three different mass ratios (w₂/w₃=4 and 7, w₃=0) by using a visual polythermal method. The solubility of the suggested systems was better than that of lithium bromide in water.     

1-丁基-3-甲基咪唑表面活性离子液体的界面膨胀流变行为研究

研究了1-丁基-3-甲基咪唑十二烷基硫酸盐([bmim][DS])和1-丁基-3-甲基咪唑二(2-乙基己基)磺基琥珀酸酯盐([bmin][AOT]两种表面活性离子液体在正庚烷/水界面的动态界面张力和膨胀特性。比较了[bmim][DS]或[bmin][AOT]和传统表面活性剂十二烷基硫酸钠(SDS)或二(2-乙基己基)磺基琥珀酸酯钠(Na[AOT])之间的膨胀弹性,并且考察了1-丁基-3-甲基咪唑阳离子之间静电相互作用对界面膜特性的影响。另外,通过对比[bmim][DS]和[bmim][AOT]在不同浓度下的膨胀弹性,验证了烷基链数量的改变对界面膨胀流变行为的影响。     

Measurement and Prediction of Vapor Pressure for H2O+CH3OH/C2H5OH+[BMIM][DBP] Ternary Working Fluids

The ionic liquid, 1-butyl-3-methylimidazolium dibutylphosphate ([BMIM][DBP]) was prepared and the vapor pressures of three set of binary solutions H2O(1)/CH3OH(1)/C2H5OH(1)+[BMIM][DBP](2) were measured...     

离子液体[BMIM][DBP]+水+甲醇/乙醇三元工质溶液蒸汽压的测量和预测(英文)

The ionic liquid, 1-butyl-3-methylimidazolium dibutylphosphate ([BMIM][DBP]) was prepared and the vapor pressures of three set of binary solutions H2O(1)/CH3OH(1)/C2H5OH(1) + [BMIM][DBP](2) were measured at different temperature and in the ILs mole fraction range from 0.1 to 0.6 with a static equilibrium apparatus. The measured vapor pressures were correlated with Non-Random Two Liquid (NRTL) activity coefficient model and the average relative deviations (ARD) between experimental and correlated vapor pressures for these binary solutions were 3.19%, 2.42% and 2.95%, respectively. Then, the vapor pressures of two set of ternary solutions H2O(1) + CH3OH(2)/C2H5OH(2) + [BMIM][DBP](3) were measured with an inclined boiling apparatus and further predicted with NRTL activity coefficient model based on the binary interaction parameters coming from fitting the vapor pressures of the binary solutions. The results indicated that the ternary solutions containing [BMIM][DBP] were shown a strong negative deviation from Raoult’s Law when the mole fraction of [BMIM][DBP] was larger than 0.2, which meant that ternary solutions could absorb the refrigerant vapors at the same or below solution temperature. Meanwhile, the average relative deviations between experimental and predicted vapor pressures for ternary solutions were 2.92% and 3.06%, respectively. Consequently, the NRTL active coefficient model used for non-electrolyte solutions was still valid for predicting vapor-liquid equilibrium of binary or ternary solutions containing ILs.     

乙腈+水+离子液体等压汽液平衡测定与计算

采用改进的Ellis平衡蒸馏仪测定了乙腈+水+1-乙基-3-甲基咪唑磷酸二乙酯盐([EMIM][DEP])、乙腈+水+{1-乙基-3-甲基咪唑醋酸盐([EMIM][OAC])+[EMIM][DEP]}常压(101.3 kPa)等压汽液平衡(VLE)数据。实验结果表明，备选离子液体可促进水+乙腈混合物的分离并消除其共沸点。借助NRTL模型成功关联了含离子液体的三元和四元VLE实验数据，获得了乙腈-[EMIM][DEP]、水-[EMIM][DEP]和[EMIM][OAC]-[EMIM][DEP]二元交互作用参数。应用COSMO-SAC预测了实验VLE，结果令人满意。量化计算表明可与水形成强相互作用的离子液体更易促进乙腈与水的分离。     

Ionic liquids as entrainer in extractive distillation for effectively separating 1-propanol–water azeotropic mixture

Economically separating 1-propanol (NPA) from water is an emergent issue for producing pharmaceutical intermediates such as n-propyl acetate, n-propylamine and so on. In this work, fourionic liquids (ILs) 1-ethyl-3-methylimidazolium thiocyanate ([EMIM][SCN]), 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF₄]), 1,3-dimethylimidazolium methylsulfate ([MMIM][MS]), 1,3-dimethylimidazolium dimethylphosphate ([MMIM][DMP]) were introduced as potential entrainers for separating NPA–water azeotropic mixture. The results show that [MMIM][MS] is the most suitable entrainer compared with other ILs from the analysis of vapor–liquid equilibrium and relative volatilities. The extractive distillation process with the entrainer regeneration system of flash tank and stripper was employed and optimized by the two-step optimization method. The results show that total annual cost and energy consumption per product flow rate were reduced by 39.79% and 60.47% compared with literature. In addition, the efficiency indicator of extractive section, efficiency indicator of per tray in extractive section, carbon dioxide emissions were also selected as the evaluation index for selection of operating parameters and calculated for different cases. The CO₂ emissions of the optimal design can be reduced by 60.98% from environmental aspect.     

咪唑类离子液体混合物用于二氧化硫高效吸收

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。     

High capacity absorption of SO2 using imidazole ionic liquid mixtures

The capture of sulfur dioxide (SO₂) with readily available and cost-effective ionic liquids (ILs) is one of the challenges for the application of ILs. Here, we synthesized the ILs mixtures with different molar ratios (3∶1, 2∶1, 1∶1, 1∶2, and 3∶1) of 1-ethyl-3-methylimidazolium chloride ([Emim][Cl]) and 1-ethyl-3-methylimidazolium acetate ([Emim][OAc]) to study their SO₂ absorption capacities. The SO₂ solubilities in these mixtures were investigated under different conditions. The SO₂ absorption capacities of [Emim][Cl]_x[OAc]_1-x at different temperatures and SO₂ partial pressure were measured. The results show that ILs can effectively capture SO₂. There exists a synergistic promotion effect between [Emim][Cl] and [Emim][OAc], resulting in quite high SO₂ absorption capacity. The [Emim][Cl]_0.33[OAc]_0.66 mixture can capture SO₂ (1.34±0.08) and (0.74±0.05) g/g at 1.0 and 0.2 atm(1 atm=101325 Pa), respectively. Comparing with the reported data, [Emim][Cl]_x[OAc]_1-x mixtures show obvious advantage for SO₂ capture. In addition, these ionic liquid mixtures have good reversibility for the absorption and desorption of sulfur dioxide.     

Insight into the behavior at the hygroscopicity and interface of the hydrophobic imidazolium-based ionic liquids

How to completely remove the water from ionic liquids(ILs) is difficult for researchers because of the hygroscopicity of ILs. In order to study the hygroscopicity of ILs, two kinds of ILs, 1-Butyl-3-methylimidazolium hexafluorophosphate([Bmim][PF_6]) and 1-Butyl-3-methylimidazolium Bis(trifluoromethanesulfonyl)([Bmim][NTf_2]) were investigated by molecular dynamics simulations. Although[Bmim][PF_6] and [Bmim][NTf_2] are hydrophobic, both of the ILs could absorb water molecules from the vapor. In this work, the process of absorbing water from the vapor phase was studied, and the water molecules could disperse into the IL. Aggregation was observed with increasing the water concentration.Although the absorbed water increases obviously, the amount of free water and small cluster in the ILs does not change significantly and always stays at a certain level. The amount of free water and small cluster in [Bmim][PF_6] is more than that in [Bmim][NTf_2], which is consistent with their hydrophobicity. In addition, the liquid-vacuum and liquid–liquid interfaces of the ILs were simulated and analyzed in detail.The number density distribution and angle distribution indicated that [Bmim]+cations arrangement regularly at the IL-vacuum interface. The butyl chain point to the vacuum, while the imidazlium ring is close to the IL phase region and perpendicular to the interface. While at the IL-water interface, the cations and anions are disordered.     

离子液体混合溶剂预处理后孟宗竹的热解

使用1-丁基-3-甲基咪唑氯化盐([Bmim]Cl)、1-丁基-3-甲基咪唑四氟硼酸盐([Bmim]BF₄)和1-丁基-1-甲基吡咯烷氯化物([Bmpy]Cl)与水并添加固体酸催化剂Nafion^®NR50组成的混合溶剂对孟宗竹进行预处理比较研究,分析了处理后孟宗竹的成分含有量、结晶结构和表面形貌等变化。把处理后的孟宗竹应用于热解研究中,通过TG-DTA和GC-TCD的分析,发现[Bmim]Cl离子液体的混合溶剂处理后的孟宗竹更易于热解反应;此外热解产物更多地从焦炭转化成气体产物;其中添加固体酸的混合溶剂预处理后的1.0 g孟宗竹样品中,在热解反应后焦炭含量为0.19 g,低于未处理样品的0.24 g;生成约0.12 g气体产物大于未处理样品的0.04 g。并探讨了离子液体混合溶剂作为一种新型前处理溶剂应用于生物质热解研究中的潜力和问题。     

Effects of imidazolium-based ionic liquids on the isobaric vapor–liquid equilibria of methanol + dimethyl carbonate azeotropic systems

The separation of methanol(MeOH) and dimethyl carbonate(DMC) is important but difficult due to the formation of an azeotropic mixture. In this work, isobaric vapor–liquid equilibrium(VLE) data for the ternary systems containing different imidazolium–based ionic liquids(ILs), i.e. MeOH + DMC + 1-butyl-3-methy-limidazolium bis[(trifluoromethyl)sulfonyl]imide([Bmim][Tf_2N]), MeOH + DMC + 1-ethyl-3-methyl-imidazolium bis[(trifluoromethyl)sulfonyl]imide([Emim][Tf_2N]), and MeOH + DMC + 1-ethyl-3-methylimidazolium hexafluorophosphate([Emim][PF6])) were measured at 101.3 kPa. The mole fraction of IL was varied from0.05 to 0.20. The experimental data were correlated with the NRTL and Wilson equations, respectively. The results show that imidazolium-based ILs were beneficial to improve the relative volatility of MeOH to DMC,and [Bmim][Tf_2 N] showed a much more excellent performance on the activity coefficient of MeOH. The interaction energies of system components were calculated using Gaussian program, and the effects of cation and anion on the separation coefficient of the azeotropic system were discussed.