离子色谱法测定哌嗪

用２．０ｍｍｏｌ／Ｌ盐酸溶液和２．０ｍｍｏｌ／Ｌ间苯二胺溶液在ＣＧ３的阳离子柱，用抑制电导检测对哌嗪进行分析，分析结果良好，并可用于实际样品中的哌嗪的测定，具有快速、灵敏、方便的特点。     

普通离子液体和功能化离子液体的合成研究进展

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.     

室温离子液体——新型的精细化学品

离子液体,简单的说就是全部由有机阳离子和有机或无机阴离子组成的有机液体盐。其中,高温融盐融熔氯化钠熔点>800℃,需高温,有强腐蚀,难于操作和应用;室温离子液体熔点<100℃,弱腐蚀性,无污染,易操作。     

新型离子液体的合成及其阳离子基团缓蚀性能

以高纯环烷酸为原料,合成了一系列含咪唑啉环的新型离子液体Ⅰ～Ⅴ,探讨了阳离子咪唑啉基团中N_（3）原子上取代基与缓蚀性能的关系.采用碳钢挂片失重法和电化学测试法,评价了它们在酸性溶液中的缓蚀性能;采用量子化学法和极化效应指数法,分别计算了离子液体Ⅰ～Ⅴ阳离子咪唑啉基团的前线轨道能量及其相应的PEI等参数.实验结果和理论分析表明：离子液体Ⅰ～Ⅴ阳离子咪唑啉基团的缓蚀效率呈现如下关系,Ⅴ＞Ⅳ＞Ⅲ＞Ⅱ＞Ⅰ;其缓蚀效率与E_HOMO、ΔE_L-H和PEI等参数间均具有良好的线性关系.     

离子液体的研究进展

离子液体作为一种新型的绿色物质,具有众多优异的物理化学性质,可通过合适的分子设计调节阴阳离子合成特殊性能离子液体,具有广阔的应用前景。在此,对离子液体作为溶剂和电池电解质两个方面的研究进展做一简要综述,同时对离子液体应用研究中存在的问题和今后的研究方向作一简单探讨。     

基于N,N'-二（3-吗啉基丙基）哌嗪三核阳离子酸性离子液体的合成及其催化作用

合成出了两种基于N,N'-二(3-吗啉基丙基)哌嗪[(mp)2pi]的三核阳离子型酸性离子液体——N,N'-二(3-吗啉基丙基)哌嗪四(三氟甲烷磺酸)盐{[(Hmp)2h2pi](OTf)4}和N,N'-二(3-吗啉基丙基)哌嗪四(硫酸氢)盐{[(Hmp)2h2pi](HSO4)4}。选取含相同内核的吗啉和哌嗪单、双阳离子的离子液体以及传统工业酸催化剂硫酸作为对照,在环己酮与苯甲醛之间的交叉Aldol反应中考察了4种酸性离子液体及硫酸的催化活性,实验结果表明,具有三核阳离子的酸性离子液体的催化活性比包含部分相同结构的单、双阳离子的离子液体及硫酸的强。其中,[(Hmp)2h2pi](OTf)4)的催化活性最强,在反应温度100℃,n(环烷酮)∶n(芳醛)=1∶1.2,催化剂用量x([(Hmp)2h2pi](OTf)4)=30%n(酮)时最高产率可达89%。催化剂重复使用6次后仍然具有一定的催化活性。     

新型纤维素溶剂——离子液体

对用于溶解纤维素的离子液体的种类、溶解机理、所形成的纤维素／离子液体溶液的性质、在再生纤维素制品制备中的应用及离子液体的回收进行了综述。     

离子液体；石油沥青质的新型溶剂

The dissolution of petroleum asphaltenes with ionic liquids is studied for the first time. The results show that the ionic liquids could be used as novel solvents for asphaltenes. The important parameters governing the ability of ionic liquids for dissolution of asphaltenes are discussed. It is found that, the ionic liquids based on the cations containing a conjugated aromatic core or the anions which are strong hydrogen bond acceptors are most effective, whereas the ionic liquids containing ＇non coordinating＇ anions such as [BF4]^- and [PF6]^- are nonsolvents for asphaltenes. Increase in the effective anion charge density enhances the ability of ionic liquids to break the extensive asphaltene associations and thus enhances the solubility of asphaltenes in the ionic liquid. The dissolution ability of ionic liquid decreases apparently with increasing the substituted alkyl chain length of its cationic head ring. Temperature is found to play an important role on dissolution of asphaltenes, and the dissolution can be significantly imoroved bv microwave heatinz.     

离子液体法新型再生纤维素纤维的研究

采用离子液体1-乙基-3-甲基咪唑醋酸盐([EMIM]Ac)为溶剂,制备了纤维素/[EMIM]Ac溶液,研究了该体系的流变性能,利用干喷湿纺的方式制备的新型再生纤维素纤维,并对纤维的结构与性能进行了分析。结果表明,纤维素/[EMIM]Ac溶液为典型的切力变稀流体,在较高剪切速率下,纺丝溶液的黏度变化较小;由该体系制备的新型再生纤维素纤维具有纤维素Ⅱ晶型的结构;随着拉伸比的提高,纤维的取向程度及结晶度增大,纤维力学性能提高。以离子液体为溶剂制备的再生纤维素纤维表面光滑,质地紧密。     

氨基离子液体的应用

介绍了氨基离子液体在固定CO2、有机合成、煤化工等方面的应用,阐述了CO2在氨基功能化离子液体中的溶解机理。指出应用过程中存在的问题。     

A new family of ionic liquids based on the 1-alkyl-2-methyl pyrrolinium cation

Five new salts based on 1-alkyl-2-methyl pyrrolinium ion are reported, two involving the iodide ion and three involving the bis(trifluoromethanesulfonyl) amide ion. The iodide salts have melting points around 100 °C, while the amide salts have melting points around room temperature. Two of the amide salts can be easily quenched into the glassy state and exhibit glass transition temperatures around −70 °C. The 2-methyl pyrrolinium cation bears structural similarities to the aromatic imidazolium cations on one hand and the cyclic ammonium cation family based on the pyrrolidinium cation on the other. The properties of the salts reported here are compared within these two related families of salts.     

基于离子液体的N,N-二甲基乙酰胺回收工艺

针对N,N-二甲基乙酰胺（DMAC）水溶液回收,研究和开发了以离子液体（IL）为萃取剂的萃取-精馏技术。通过COSMO-RS对384种IL组合在无限稀释条件下对DMAC的溶解能力C进行量化预测,优化获得了潜在的1-丁基-3-甲基咪唑三(五氟乙基)三氟磷酸[BMIm]FEP萃取剂。计算了[BMIm]FEP-DMAC-H₂O三元体系的液液相平衡数据,并通过NRTL方程拟合获得了二元交互参数,设计了萃取流程。研究结果表明：在DMAC初始含量为10%、[BMIm]FEP/DMAC水溶液质量比为2∶1、萃取塔理论板为20块时,可以回收水溶液中99.5%的DMAC。为进一步评价[BMIm]FEP作为萃取剂的可行性,对工艺进行了能耗计算,同时对比了纯精馏工艺和以氯仿为萃取剂的萃取-精馏工艺,结果表明,以[BMIm]FEP为萃取剂的萃取-精馏工艺更为节能,分别较前两者工艺节能90%和50%以上,在处理低浓度DMAC水溶液时,具有明显的优势。     

Effect of small cation addition on the conductivity of quaternary ammonium ionic liquids

Several quaternary ammonium or lithium bis(trifluoromethane sulfone) imide (TFSI) salts were dissolved into N,N,N,N-hexyltrimethyl ammonium TFSI ionic liquid, and the conductivities of the resulting solutions were measured. Some asymmetric quaternary ammonium salts contributed to increase the conductivity of the solution, while cyano-containing quaternary ammonium and lithium salts decreased the conductivity. Based on the results of differential scanning calorimetry (DSC) measurements, such conductivity behaviors appeared to be related to the intrinsic miscibility of the ionic liquid solutions.     

Monodispersed mesoporous silica nanospheres based on pyridinium ionic liquids

In the past decades, ionic liquids (ILs) have garnered a lot of attention especially in the field of green chemistry due to their unique properties which help to solve the problems posed by organic solvents. Interestingly, their applications are not limited to that only as ILs have the potential to become alternative templates in the development of mesoporous silica nanoparticles (MSNs). This work reported the usage of a series of pyridinium ILs as template in the synthesis of monodispersed mesoporous silica nanosphere (MNSs) via two methods. Both syntheses utilize triethanolamine (TEA) as the base catalyst where in one method the TEA undergoes pre-treatment process while the other did not. Besides that, the effects of pyridinium ILs alkyl chain length were also investigated. MNSs generated via both methods exhibit spherical morphology and decreasing average particles size with increasing alkyl chain length of pyridinium ILs. The MNSs porosity were further analyzed through nitrogen sorption analysis where the surface area were in between 71.85 and 525.02 m² g^?1 and the pore volume was up to 1 cm³ g^?1.     

基于离子液体的清洁化技术研究进展

重点介绍离子液体在燃油脱硫技术和催化烷基化等清洁工艺方面的应用进展以及工业化关键技术,析了离子液体在工业化过程中的应用方向和亟待解决的问题.     

COSMO-RS based predictions for the desulphurization of diesel oil using ionic liquids: Effect of cation and anion combination

Ionic Liquids ILs provide an important alternative in removing aromatic sulphur compounds by Liquid-Liquid Extraction (LLE). A total of 28 anions and 6 cations resulting in 168 possible combinations were screened via COSMO-RS (COnductor Like Screening MOdel for Real Solvents). Initially benchmarking was performed to predict the infinite dilution activity coefficients of thiophene in ionic liquids. Comparison with literature values involving 8 ILs with 20 points gave the average root mean square deviation (RMS) to be 11%. Thereafter artificial simulated diesel, aromatic sulphur compound and the cation and anion combination was used to predict the capacity (C) and selectivity (S) at infinite dilution. In general the selectivities were found to decrease in the following order: thiophene (4-24) > benzothiophene (2-12)> dibenzothiophene (1-7). The different hetero atom (N,S,O) and its location in the cation structure strongly influenced the selectivity and capacity at infinite dilution for all the three aromatic sulphur compounds. It was found that the cation without the aromatic ring combined with anions having sterical shielding effect such as [SCN], [CH₃SO₃], [CH₃COO], [Cl], and [Br] proved to be the most favourable IL for desulphurization. [EMMOR][SCN] proved to be the most viable IL for the removal of all the three aromatic sulphur compounds.     

微波控制下咪唑类离子液体的制备

以N-甲基咪唑和氯代正丁烷为原料在微波控制下合成了离子液体1-丁基-3-甲基咪唑氯盐([BMIm]Cl),对产物的结构作了红外光谱、核磁共振等分析。用该离子液体溶解纤维素,溶解度良好,并对溶解前后纤维素的结构变化、溶解机理进行了研究。     

己基乙二胺-TFS型质子化离子液体与水分子间氢键相互作用的研究

通过前期实验研究,己基乙二胺-三氟甲磺酸([HHex][TFS])型质子化离子液体(protic ionic liquid,PIL)的极性部位具有两个氨基,亲水性较强,能够与水混溶90%(质量)(H₂O/ PIL)以上。因此利用密度泛函理论(density functional theory,DFT),在M06-2X/6-311G(d,p)的水平下,对 [HHex][TFS]与H₂O分子间形成的氢键作用进行了研究。设计了[HHex][TFS]分别与nH₂O (n = 1, 2, 6) 相结合的构型,并得到了较稳定构型共8种(S1~S8),计算了其分子间的相互作用能(ΔE ₀ ^BSSE)、分子振动频率(Δν)、二阶微扰能、电子密度(ρ _c)以及Laplace值(?² ρ _c)。分析结果显示,[HHex][TFS]与水分子间形成了较强的氢键,[HHex][TFS]与H₂O结合数量增加,构型中氢键相互作用增强,即S4(n=1)＜S6(n=2)＜S8(n=6)。     

Sugar-derived ionic liquids

Ionic liquids (ILs) are special molten salts with melting points below 100 degrees C that are typically constituted of organic cations (imidazolium, pyridinium, sulfonium, phosphonium, etc.) and inorganic anions. Due to their ionic nature, they are endowed with high chemical and thermal stability, good solvent properties, and non-measurable vapor pressure. Although the recycling of ILs partly compensate their rather high cost, it is important to develop new synthetic approaches to less expensive and environmentally sustainable ILs based on renewable raw materials. In fact, most of these alternative solvents are still prepared starting from fossil feedstocks. Until now, only a limited number of ionic liquids have been prepared from renewable sources (e.g., hydroxy acids, amino acids, terpenes), and even less from naturally occurring carbohydrates. This short review describes the synthesis and applications of chiral and achiral ILs obtained from inexpensive sugars.