Jump to content

User:Gokulramadoss/sandbox

From Wikipedia, the free encyclopedia

Our group decided to edit the Ionic Liquids in Carbon Capture article. I in particular will be adding a section on commercial examples of ionic liquids in carbon capture or at least listing/tabulating different categories and types of ionic liquids used. I might also be interested in the oxycombustion article as a backup, but the ionic liquids in carbon capture article is my preferred article. Our group has already started writing.

Draft of my contribution ("Examples" Section):

The properties of ionic liquid solvents can be tuned by the selection of cation and anion components from a broad variety of options. While anion trends typically have higher correlation with carbon dioxide solubility, both the cation and the anion contribute to the solvent’s physical and chemical properties. Commonly used cations with dramatically different structures include ammonium, guanidium, imidazolium, morpholinium, piperidinium, and pyridinium [1]. These structures are often modified with the addition of alkyl chains or other functional groups; for example, among the most commonly used cations in ionic liquids is “bmim” or 1-butyl-3-methylimidazolium. Longer alkyl chains on the cation have been shown to increase carbon dioxide solubility [1]. Commonly used anions are usually inorganic [2], and include bis(trifluoromethylsulfonyl)imide (“Tf2N”), hexafluorosphate (“PF6”), and tetrafluoroborate (“BF4”). One example of a trend in the anion’s effect on carbon dioxide solubility is that solubility increases with the number of fluorines in the anion [1]. Numerous combinations of cations and anions have been tested as potential solvents for carbon capture, and new ion components continue to be designed.

While ionic liquids have been tested alone as carbon capture solvents, combining ionic liquids with other solvent systems could provide additional flexibility in tuning physical properties. For example, adding a small amount of water to an ionic liquid solvent has been shown to significantly decrease its viscosity without significantly sacrificing carbon dioxide solubility [3]. This aids in improving efficiency and reducing the energy costs associated with transport. Furthermore, adding amines and water to ionic liquid solvents has been shown to make solvent regeneration less energy-expensive, increase carbon dioxide solubility, and decrease solvent volatility [3]. Another option is combine ionic liquids with organic solvents. Some of the drawbacks unique to ionic liquid solvent systems, such as high cost and viscosity and low diffusion coefficient of gas, can be overcome by combining ionic liquids with organic solvents such as methanol [3].

1) Ramdin, Mahinder, Theo W. De Loos, and Thijs J J Vlugt. "State-of-the-Art of CO2 Capture with Ionic Liquids." Industrial and Engineering Chemistry Research 51 (2012): 8149-177.

2) "Anions." Ionic Liquids - Anions. UNIVERSITA' DI TORINO, n.d. Web. 28 Apr. 2017. <http://lem.ch.unito.it/didattica/infochimica/Liquidi%20Ionici/Anions.html>.

3) Zhang, Xiangping, Xiaochun Zhang, Haifeng Dong, Zhijun Zhao, Suojiang Zhang, and Ying Huang. "Carbon capture with ionic liquids: overview and progress." Energy & Environmental Science 5 (2012): n. pag.