An Integrated, Single Pass Analysis Chip for Ionic Liquids

在过去的十年里，离子液体作为一种替代的、环境友好的溶剂得到了发展。对清洁工业过程的推动导致了离子液体作为一系列反应的潜在首选溶剂的出现，这些反应以前被认为是有害的，并在清洁合成、电化学和液晶等方面显示出希望。不幸的是，除了少数例外，离子液体还没有完全证明它们的可行性。这在很大程度上是因为几乎所有可用的研究都集中在化学上，而不是开发允许良好的工程所需的数据。然而，人们已经确定，离子液体溶剂具有广泛的物理性质多样性，再加上它们的低蒸汽压，使它们有可能成为工程上的首选溶剂。这些因素还允许将溶剂性质/结构作为设计变量，该设计变量可以被系统地改变以允许整个过程的最佳性能。这将使工厂的设计不受所用溶剂的限制。尽管这种设计者设计的溶剂方法在优化反应方面具有巨大的潜力，但在当前的研究中，只有少数离子液体被广泛使用。其中一个主要原因是作为化学成分的函数可获得的物性数据有限。收集这些信息是耗时的，而且对于许多必要的测量来说，需要极其昂贵的分升离子液体，其纯度和确切来源已知。如果离子液体是为满足特定工艺的需要而定制的，则需要大幅扩展物理属性数据库，以包括热效应和添加的辅助溶剂(另一种离子液体、水或有机材料)的变化。特别是，完整的物理性质分析所需的材料量需要减少大约两到三个数量级，以便获得数据的成本变得可以忽略不计。这项建议的目的是利用高通量的芯片上实验室技术，在非常小的样品上工作，从而能够快速确定非常大的组成和温度空间的性质变化。我们相信，这种数据的简单可用性将大大减少工艺工程师和化学家对在工业中使用离子液体的保留意见。

Over the past decade, ionic liquids have been developed as alternative, environment friendly, solvents. The drive towards cleaner industrial processes has led to the emergence of ionic liquids as potentially preferable solvents for a range of reactions, previously considered harmful and have shown promise in, for example, clean synthesis, electrochemistry, and liquid crystals. Unfortunately, with a few exceptions, ionic liquids have yet to prove their full-scale viability. This is due in large part to the fact that almost all of the available research has focussed on the chemistry rather than developing the data necessary to allow good engineering. However, it has been established that the wide diversity of physical properties that are available in ionic liquid solvents, coupled with their low vapour pressures, give them the potential to be the engineering solvent of choice. These factors also allow the possibility of having the solvent property/structure as a design variable that may be systematically changed to allow optimal performance of the entire process. This would enable plants to be designed without being limited by the solvent used. Despite the enormous potential of this designer solvent approach to optimising reactions, only a handful of ionic liquids are commonly used in current investigations. One of the major reasons is the limited amount of physical property data available as a function of chemical composition. This information is time consuming to collect and requires, for the many measurements necessary, extremely expensive, decilitre quantities of ionic liquid whose purity and exact provenance is known. If ionic liquids are be tailored to meet the needs of a specific process, the physical property database needs to be expanded substantially to include both thermal effects and the variation with added secondary solvent (either another ionic liquid, water or an organic material). In particular, the amount of material necessary for a complete physical property analysis needs to be brought down by about two to three orders of magnitude so that the costs of obtaining the data become negligible. The objective of this proposal is to harness high-throughput, lab-on-a-chip techniques working on very small samples to enable the rapid determination of property variation across a very large composition and temperature space.We believe that the simple availability of such data would serve massively to decrease the reservations regarding the use of ionic liquids in industry by the process engineers and chemists.