离子液体溶解纤维素的研究

纤维素是一种可生物降解的天然高分子材料,由于纤维素含有大量的分子间和分子内氢键,导致纤维素难溶于水和一般的有机溶剂。现有的溶剂存在稳定性差,具有毒性,难以回收等缺点,对纤维素的加工、利用造成困难,因此,寻找新型绿色溶剂成为纤维素开发的热点和难点。离子液体是一种新型高效绿色溶剂,在一定条件下可以溶解纤维素、角蛋白等生物大分子,离子液体的出现为纤维素的溶解提供了一种环境友好、可生物降解的溶剂体系,具有广阔的应用前景。本文就不同种类离子液体溶解纤维素的溶解度以及影响溶解度几种因素进行了综述,总结了离子液体与纤维素作用机理以及离子液体的回收方法,为纤维素的加工利用提供了理论依据和工业指导。     

离子液体--一种新型的绿色化学反应介质

离子液体是室温下表现为液体的离子化合物,近年来被开发成为一种新型绿色化学反应介质。本文简要介绍了离子液体的特点、发展历史、制备、应用等方面,并对其应用前景做了展望。我们阳信,在不久的将来,离子液体会成为绿色化学工程技术中的一枝新秀。     

离子液体的前沿、进展及应用

离子液体作为一类新型绿色介质,近年来获得了突飞猛进的发展.离子液体的多项应用研究正在进行中试或工业性试验,甚至已经进入产业化阶段.推动离子液体研究迅速发展的直接动力来源于国际社会对清洁生产、环境保护、循环经济的强烈愿望,以及离子液体本身的科学探索价值和巨大的应用潜力.离子液体不仅可替代传统有机溶剂或酸碱成功用作化工反应和分离的新介质,而且展示了作为新型磁性材料、纳微结构功能材料、润滑材料、航空航天推进剂等潜力,甚至有望成为食品和医药.     

离子色谱法在离子液体阴阳离子分析中的应用

离子液体作为一种新型绿色环保有机化合物,因具有饱和蒸气压低、溶解性良好以及电导率高等优异性质,而在化学化工领域中得到了较为广泛的应用,并越来越受到人们的关注。该文综述了近年来离子色谱在离子液体阴阳离子分析中的应用,对离子色谱法分析离子液体阳离子、离子液体阴离子以及同时分析离子液体阴阳离子三方面进行讨论,并对离子色谱法分析离子液体的发展趋势进行了展望。     

离子液体[bmim]PTSA的微波合成

近年来,随着绿色化学的兴起,离子液体作为一种新型的绿色溶剂已成为国内外科研工作者的研究热点之一.离子液体是由有机阳离子和无机阴离子组成的盐,可以根据需要控制阴阳离子的组成和结构,设计合成出不同特性的离子液体[1].     

离子液体在生物质利用方面的应用

能源和环境危机日益严重,生物质作为唯一可再生的碳源,其开发利用备受关注.同时离子液体因其不挥发、较好的稳定性和可重复利用等优点,可作为新型绿色溶剂.近年来,离子液体和生物质利用的研究交叉渗透,研究者们完成了一系列离子液体在生物质利用方面的应用研究.本文主要从生物基离子液体和离子液体作为生物质利用的介质两方面对该研究进行...     

基于离子液体电解液的有机电化学反应

室温离子液体(RTILs) 作为一类在室温时呈液态且具有良好导电性的新型绿色溶剂, 在有机电化学反应体系中的应用前景广阔。本文介绍了近年报道过的新型离子液体及离子液体电解液的特性,阐述了基于离子液体电解液的电化学实验方法,重点综述了离子液体中的各种有机电化学反应,包括电化学还原反应、CO₂在离子液体中的电化学固定、电化学氧化反应、烯烃的环氧化、选择性氟化反应、偶联反应、功能化有机硅氧烷的合成、电化学氟化脱硫反应、电化学聚合反应等,并展望了发展趋势。     

离子液体的进展——绿色制备及在环境修复中的应用研究

近年来,离子液体由于其独特的性能在实验室和工业领域得到广泛研究,并展示出良好的应用前景.同时,一系列离子液体绿色制备技术被开发设计出来,极大地改变了离子液体的研究面貌.本文综述了离子液体的绿色制备及在环境修复中的应用进展.离子液体的绿色合成主要途径有,原子经济性反应、绿色原材料合成、绿色溶剂合成、化工过程强化技术及计算机辅助设计,表现出合成效率高、产品质量好、废物产生量少、能耗低、合成条件温和等特点.离子液体的绿色制备不仅使离子液体更加丰富多彩,而且使其"从头到脚"成为一种绿色溶剂和绿色功能材料.离子液体在环境修复的典型特点和独特优势表现在:在水体修复方面,具有分离效率高、不产生二次污染、耗材少等特点;在土壤修复中,可以有效削弱污染物质在土壤中的毒性;在大气修复中,在消除污染物的同时,有时可以实现其资源化利用.展望了离子液体在绿色制备和环境修复的未来发展趋势.     

基于离子液体的绿色催化过程

离子液体为构建绿色催化反应过程提供了新途径.本文简要评述了离子液体在几个代表性催化反应中的研究进展,如CO2羰基化、烷基化、酯交换、氧化、CO2加氢、共聚以及PET降解等;分析讨论了离子液体的特点和优势,如提高反应活性、降低废物排放以及简化分离等,并对离子液体催化反应的未来发展方向进行了展望.     

离子液体与生物大分子相互作用研究进展

离子液体作为一类新型绿色溶剂,因其独特的理化性质,被广泛应用于催化、有机合成、分离富集和电化学等领域。其中,离子液体在生物大分子的分离纯化、催化和降解方面显示出良好的应用前景,成为研究的热点领域之一。本文从离子液体与生物大分子的本质关系出发,对离子液体在DNA和蛋白质的分离纯化、酶的活性稳定性和天然纤维素溶解等过程中与生物大分子之间的相互作用进行了综述。     

离子液体中的不对称催化反应*

对价格昂贵的手性催化剂进行回收和重复利用是目前不对称催化领域面临的难题之一,受到学术界和工业界的共同关注。化学家们已经尝试了许多方法,其中使用离子液体来替代常规有机溶剂使催化剂得到分离和重新使用已经引起他们极大的兴趣。本文综述了近年来在离子液体中进行不对称催化反应的研究进展,对离子液体中过渡金属和有机小分子催化的各种反应进行重点介绍,强调了离子液体不但在催化剂回收方面有独特优势,而且在许多反应中能够提高催化效率。     

核磁共振波谱技术在室温离子液体研究中的应用*

室温离子液体作为一种绿色溶剂和功能材料,越来越引起人们的重视,其研究手段也越来越多。本文着重概述了核磁共振方法在测定离子液体的结构、纯度及性质,研究离子液体阴阳离子间的相互作用、离子液体与其他化合物的相互作用、离子液体及其在混合体系中的动力学特征、离子液体在溶液中的聚集行为,以及测定离子液体的热力学参数中的应用。     

含能盐和含能离子液体

近年来含能盐和含能离子液体由于其独特的性质而受到广泛关注。本文综述了多种含能盐和含能离子液体（阳离子包括三唑、四唑、双环唑、六次甲基四胺等;阴离子包括硝酸根、高氯酸根、硝基唑、叠氮根、四硝基铝、多腈基化合物、二硝基尿素等）的合成;结合其表征结果分析了阳离子上的取代基以及阴阳离子对它们的性能如熔点、生成焓、密度等的影响。对含能盐和含能离子液体在炸药和推进剂方面的应用进行了展望。     

Electrodeposition onto magnesium in air and water stable ionic liquids: From corrosion to successful plating

Magnesium is very reactive and therefore magnesium electroplating in aqueous solutions is hazardous. Mg is classified as a water sensitive substrate from the electrodeposition point of view. Therefore, it was suggested that ionic liquids be used as electrolytic solvents for electrodeposition onto Mg and its alloys. Five air and water stable ionic liquids based on choline chloride (ChCl) were investigated to deposit Zn onto several Mg alloys in air. The ChCl/urea mixture was found to be the most feasible liquid for successful electrodeposition. Other liquids produced powdery deposits or resulted in corrosion of Mg substrate. Application of a pulsed current was superior to a constant current in producing smooth, sealed and more corrosion-resistant Zn layers.     

Reversible physical absorption of SO2 by ionic liquids

Ionic liquids can reversibly absorb large amounts of molecular SO(2) gas under ambient conditions with the gas captured in a restricted configuration, possibly allowing SO(2) to probe the internal cavity structures in ionic liquids besides being useful for SO(2) removal in pollution control.     

Highly efficient and reversible SO2 capture by tunable azole-based ionic liquids through multiple-site chemical absorption

A novel strategy for SO(2) capture through multiple-site absorption in the anion of several azole-based ionic liquids is reported. An extremely high capacity of SO(2) (>3.5 mol/mol) and excellent reversibility (28 recycles) were achieved by tuning the interaction between the basic anion and acidic SO(2). Spectroscopic investigations and quantum-mechanical calculations showed that such high SO(2) capacity originates from the multiple sites of interaction between the anion and SO(2). These tunable azole-based ionic liquids with multiple sites offer significant improvements over commonly used absorbents, indicating the promise for industrial applications in acid gas separation.     

超临界CO2/离子液体体系

超临界CO2和离子液体是两种具有优异性能的绿色化学试剂,本文介绍了将两者结合反应,分离体系的物化性质和多种绿色化学过程。利用超临界CO2可以广泛地萃取离子液体中的不挥发性化合物而不导致离子液体及其中催化剂的流失,在加氢、醛化、甲酰化等反应,分离过程中的应用表明,过程具有很好的反应分离特性和环境友好性,应用前景广阔。     

Removal of ionic liquids and ibuprofen by adsorption on a microporous activated carbon: Kinetics,isotherms, and pore sites

Ionic liquids (ILs) are considered as emergent pollutants as their synthesis and further use at a large scale might generate environmental problems. The adsorption on activated carbons represents one of the most effective methods to remove ionic liquids and other micropollutants from wastewater. In this work, the adsorption properties on an activated carbon cloth of two pyridinium ionic liquids (4-tert-butyl-1-propylpyridinium bromide (IL1) and 4-tert-butyl-1-(2-carboxyethyl)pyridinium bromide (IL2)) newly synthesized, were compared with the ones of ibuprofen. The adsorption kinetics and isotherms were studied at pH 3 and 7.5. The adsorption thermodynamic parameters calculated from the isotherms indicate an exothermic process, typical of physisorption. The adsorption kinetics of a mixture of the molecules show a competition between ibuprofen and IL2. The location of each adsorbed ionic liquid and ibuprofen into the porosity of the activated carbon cloth was determined from N₂ (at 77 K) and CO₂ adsorption isotherms (at 273 K). The purification process of an effluent containing the ionic liquids and the ibuprofen in mixture or in single solute could be workable by adsorption on an activated cloth.     

Ionic Liquids for the Chemical Recycling of Polymeric Materials and Control of Their Solubility

Plastics are wonderful materials that have modernized our daily life; however, importance of effective recycling of plastics is gradually recognized widely. In this account, we describe our discovery of new and efficient methods for the chemical recycling of plastics using ionic liquids (ILs). Since the chemical recycling usually requires high temperature conditions to breakdown chemical bonds in polymeric materials, we thought that less-flammability and non-volatility of ionic liquids are the most suitable physical properties for this purpose. Ionic liquids successfully depolymerized polyamides and unsaturated polyesters smoothly and corresponding monomeric materials were obtained in good yields. To the best of our knowledge, this was the first use of Ionic liquids for such reactions. However, we encountered another difficult problem-separation. To solve the problem, we developed solubility-switchable ionic liquids, a new type of ionic liquids in which solubility is readily changed using the chemistry of protective groups. Conversion between hydrophilic and lipophilic forms was readily achieved using a simple chemical treatment under mild conditions, and the complete separation of products was achieved by liquid-liquid-extraction. The robustness of either form unlocks their wide use as reaction solvents.     

Tuning the physicochemical properties of diverse phenolic ionic liquids for equimolar CO2 capture by the substituent on the anion

Phenolic ionic liquids for the efficient and reversible capture of CO(2) were designed and prepared from phosphonium hydroxide and substituted phenols. The electron-withdrawing or electron-donating ability, position, and number of the substituents on the anion of these ionic liquids were correlated with the physicochemical properties of the ionic liquids. The results show that the stability, viscosity, and CO(2)-capturing ability of these ionic liquids were significantly affected by the substituents. Furthermore, the relationship between the decomposition temperature, the CO(2)-absorption capacity, and the basicity of these ionic liquids was quantitatively correlated and further rationalized by theoretical calculation. Indeed, these ionic liquids showed good stability, high absorption capacity, and low absorption enthalpy for CO(2) capture. This method, which tunes the physicochemical properties by making use of substituent effects in the anion of the ionic liquid, is important for the design of highly efficient and reversible methods for CO(2)-capture. This CO(2) capture process using diverse phenolic ionic liquids is a promising potential method for CO(2) absorption with both high absorption capacity and good reversibility.