Proposed Content for Ionic Liquids in Carbon Capture (27 Apr 2017)

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Benefits

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Generally, ionic liquids have low volatility, good thermal and chemical stabilities, and a small environmental impact, while having a good CO2 absorption capacity. Ionic liquids are also receiving scientific attention for their high tunability.

Volatility

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Ionic liquids have low volatility. Some ionic liquids have been demonstrated to be easily distilled at low pressure and temperature of 200–300 °C without decomposition[1].

Thermal Stability

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Thermal stability refers to the ability of the ionic liquid to resist thermal decomposition, or changes in chemical or physical structure, at elevated temperatures.

Some Imidazolium and Phosphonium-based ionic liquids have been shown to be very thermally stable[2][3], with cases of up to 450˚C, making them suitable for reactions taking place above 100˚C. The thermal stability of ionic liquids is limited by the strength of the hydrogen bonds and bonds between the carbon atoms and other types of atoms. Thermal stability is affected by the choice of ions. For example, increasing the substitution of the imidazolium ions increases the thermal stability due to the removal of the ring hydrogens. The presence of catalysts will also affect thermal stability. For example, imidazolium PF6 salts are strongly affected by the presence of aluminium, with a drop of 100˚C lower thermal stability when compared to the presence of alumina[4].

Chemical Stability

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The electrochemical window is the electrochemical potential range over which the electrolyte is neither reduced nor oxidized at an electrode. This value determines the electrochemical stability of solvents. Water has a low electrochemical window of only about 1.2 V, while ionic liquids like BMIm-based ILs have windows of 4 to 5.5 V, allowing for electrodeposition of many elements at room temperature instead of at high temperatures[5].

In addition, phosphonium-based ionic liquids show good stability in the presence of bases, even in reactions involving strong bases such as Grignard reagents[6].

Energy Intensity

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Theoretical work performed on ionic liquids, investigating their role as solvents for a CO2 capture plant, indicates that it is possible to achieve lower energy usage than a traditional MEA-based plant.[7]

The removal of sulfur from organic compounds, to prevent pollution, requires large amounts of energy and hydrogen. Extractive desulfurization (EDS) is an alternative, where ionic liquids can be used instead of organic solvents to achieve high energy-efficiency and high effectiveness of sulfur removal while remaining environmentally-benign[8].

Room Temperature Ionic Liquids (RTILs), which are ionic liquids that have melting points below room temperature, have been developed. Their use as absorbents and potential in polymer membranes are being explored. RTILs have the potential to be used in processes and materials aimed at CO2 capture from power plant flue gas, as well as in natural gas sweetening[9].

Environmental Impact

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Traditional organic solvents, if not properly managed, often evaporate into the atmosphere with harmful effects on the environment and human health. Ionic liquids, characterized by extremely low vapor pressures, can be used as environmentally-benign media for a variety of chemical processes[10]. With the correct choice of ionic liquid, higher product yields can be obtained, and a reduced amount of waste can be produced in a given reaction. Usually, the ionic liquid can also be recycled, which reduce the costs of the processes. [11]

Ease of Synthesis

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Reactions in ionic liquids are not difficult to perform and usually require no special apparatus or methods. The reactions are often quicker and easier to carry out than with conventional organic solvents.[11]

Methods and examples of synthesis[12]:

Categorization (Not adding to article)

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Ionic liquids can be categorized by their cation. Four popular cation categories are: alkylammonium-, dialkylimidazolium-, phosphonium- and N-alkylpyridiniumbase ionic liquids.[13]

Ammonium-based ionic liquids are increasingly utilized as electrolytes in high-energy electrochemical devices because of their large electrochemical windows, low melting points and low viscosities[14][15][16].

Imidazolium-based ionic liquids are widely studied. The property that makes the imidazolium ion popular is that the imidazolium ring stabilizes it for both oxidative and reductive conditions[17]. The resulting ionic liquid usually has low viscosity and is generally easy to prepare[18]. Imidazolium-based ionic liquids have been studied for their role as catalysts with regards to improving the reaction time, yield, and chemoselectivity of many organic reactions[19].

Phosphonium-based ionic liquids are the newest category of ionic liquids to receive scientific attention. They are more thermally stable, in some cases up to nearly 400˚C[20], in comparison with ammonium and imidazolium salts, making them suitable for reactions taking place above 100˚C. Recently, phosphonium-based ionic liquids have been used for CO2 capture[21]. In addition, these ionic liquids show good chemical stability, such as in the presence of bases, even in reactions involving strong bases, like Grignard reagents[6].

Pyridinium-based ionic liquids are more novel in comparison with their imidazolium-based counterparts, and research on their stability, reactivity and catalytic role in organic synthesis is still in progress. The catalytic role of pyridinium-based ionic liquids has been shown to be remarkable in the synthesis of some pharmaceutical agents[22][23][24].

Drawbacks (Not adding to article)

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Despite their advantages over the conventional physical solvents, these ILs are still not ready for commercial-scale application due to its high viscosity and limited diffusivity, which could lead to unsatisfactory gas-liquid mass transfer (i.e. slow absorption rate) in the conventional absorption packed column

Wai Lip Theo, Jeng Shiun Lim, Haslenda Hashim, Azizul Azri Mustaffa, Wai Shin Ho, Review of pre-combustion capture and ionic liquid in carbon capture and storage, Applied Energy, Volume 183, 1 December 2016, Pages 1633-1663, ISSN 0306-2619, http://doi.org/10.1016/j.apenergy.2016.09.103.

(http://www.sciencedirect.com/science/article/pii/S0306261916314052) Accessed 19 April 2017.

Costly - In all cases, the process designs using ILs have higher capital costs than the MEA process by a factor of 3. This is due to the additional equipment costs related to the compression of biogas in the ionic liquid processes. Additionally, the solvent costs are considerably higher when using ILs. As for the O&M expenditure, the MEA process results in lower costs than those of the processes using ILs. This work has also revealed that production costs of biomethane using ILs as physical absorbents are 40−51% higher than a same-scale MEA-based CO2 capture process.

Pelayo García-Gutiérrez*†, Johan Jacquemin*‡, Corina McCrellis‡, Ioanna Dimitriou†, S. F. Rebecca Taylor‡, Christopher Hardacre‡, and Raymond W. K. Allen†, Techno-Economic Feasibility of Selective CO2 Capture Processes from Biogas Streams Using Ionic Liquids as Physical Absorbents, Energy Fuels, May 3, 2016, 30 (6), pp 5052–5064,

DOI: 10.1021/acs.energyfuels.6b00364

(http://pubs.acs.org/doi/pdf/10.1021/acs.energyfuels.6b00364) Accessed 19 April 2017.

Benefits

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Experimental results have shown that IL feature chemical and thermal stability and good CO2 absorption capacity. In this work, a theoretical IL is used as physical solvent for developing a new flow-sheet of a CO2 capture plant. A techno-economic analysis was carried out to evaluate the feasibility of the proposed design. The results show that the IL-based plant features lower energy demand compared to a traditional MEA-based plant. Moreover, the dynamic analysis performed in this study provides insight on the degree of nonlinearity and the dynamics of the process, which are essential tools to design suitable control schemes. The results show that the plant can accommodate perturbations in the flue gas flow rate up to ±10% while meeting CO2 recovery and purity targets.

Darinel Valencia-Marquez†, Antonio Flores-Tlacuahuac*†, and Luis Ricardez-Sandoval‡, Technoeconomic and Dynamical Analysis of a CO2 Capture Pilot-Scale Plant Using Ionic Liquids, Ind. Eng. Chem. Res., 2015, 54 (45), pp 11360–11370, DOI: 10.1021/acs.iecr.5b02544 (http://pubs.acs.org/doi/10.1021/acs.iecr.5b02544) Accessed 19 April 2017.

the studies revealed that not only the latent heat of vaporization but also the sensible heat and reaction heat of CO2 capture can be tailored by the choice of ILs. ILs can be used to tailor the amine aqueous solution to save the overall CO2 regeneration energy consumption for carbon capture in an IGCC process by the choice of anion species

Jubao Gao,, Lingdi Cao, Haifeng Dong, Xiangping Zhang, Suojiang Zhang, Ionic liquids tailored amine aqueous solution for pre-combustion CO2 capture: Role of imidazolium-based ionic liquids, Applied Energy Volume 154, 15 September 2015, Pages 771–780, (https://www.sciencedirect.com/science/article/pii/S0306261915007060) Accessed 19 April 2017.

The potential of these novel solvents has been recognised due to their low volatility, non-flammable, and recyclable natures [385]. Apart from that, they are preferred over the conventional organic solvents for their enhanced solvation potential for a wide range of organic and inorganic solutes [386], high thermal stability [387], and wide liquid range [388]. Besides, their adjustable solvent (i.e. physiochemical) properties based on the choice of constituting cations and anions [384] endow them the designation of ‘designer solvents’.

Among these experimental trials, ILs have stood out as a popular agenda due to their tunable solvent characteristics, thermal stability, minimum volatile loss, and reduced degradation-related emissions

Drawbacks

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Despite their advantages over the conventional physical solvents, these ILs are still not ready for commercial-scale application due to its high viscosity and limited diffusivity, which could lead to unsatisfactory gas-liquid mass transfer (i.e. slow absorption rate) in the conventional absorption packed column

Wai Lip Theo, Jeng Shiun Lim, Haslenda Hashim, Azizul Azri Mustaffa, Wai Shin Ho, Review of pre-combustion capture and ionic liquid in carbon capture and storage, Applied Energy, Volume 183, 1 December 2016, Pages 1633-1663, ISSN 0306-2619, http://doi.org/10.1016/j.apenergy.2016.09.103.

(http://www.sciencedirect.com/science/article/pii/S0306261916314052) Accessed 19 April 2017.

Costly - In all cases, the process designs using ILs have higher capital costs than the MEA process by a factor of 3. This is due to the additional equipment costs related to the compression of biogas in the ionic liquid processes. Additionally, the solvent costs are considerably higher when using ILs. As for the O&M expenditure, the MEA process results in lower costs than those of the processes using ILs. This work has also revealed that production costs of biomethane using ILs as physical absorbents are 40−51% higher than a same-scale MEA-based CO2 capture process.

Pelayo García-Gutiérrez*†, Johan Jacquemin*‡, Corina McCrellis‡, Ioanna Dimitriou†, S. F. Rebecca Taylor‡, Christopher Hardacre‡, and Raymond W. K. Allen†, Techno-Economic Feasibility of Selective CO2 Capture Processes from Biogas Streams Using Ionic Liquids as Physical Absorbents, Energy Fuels, May 3, 2016, 30 (6), pp 5052–5064,

DOI: 10.1021/acs.energyfuels.6b00364

(http://pubs.acs.org/doi/pdf/10.1021/acs.energyfuels.6b00364) Accessed 19 April 2017.

Proposed Edits (19 Apr 2017)

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Our group is choosing to edit the Ionic Liquids in Carbon Capture wikipedia page. We immediately noticed that this page was lacking in a solid introduction, a history section, enough references, there are no drawbacks of the technology (making it seem biased towards favoring ionic liquids over amines), lacked any mention of environmental impacts of use, and doesn’t provide many examples of commercial application. Our group would like to improve this web page by gathering articles in this area and introducing new sections about the history, commercial applications, as well as a drawbacks and benefits section. This will allow the reader to gain a more comprehensive view of ionic liquids as they pertain to carbon capture. We would like use information from the following references to achieve this.

Notes for proposal:

-history section* (Jose)

-benefits and drawbacks section: solubility, greenness, viscosity (Jiasheng & Tressa)

-commercial / commercially used examples section: table of ionic liquid, who developed it, who’s using it (Gokul)

Action items; everybody use MLA format to formally cite the references you would like to use!

Chosen Article: Ionic liquids in carbon capture (18 Apr 2017)

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Current points made in the Talk Page for ionic liquids

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  • Under-referenced
  • No drawbacks mentioned of the technology, seems biased
  • Could use more info about the tunability of ionic liquids or the loading capacities of different amines
  • Needs some commercial application information
  • Need to focus on how we apply this method to CCS

Ideas:

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  • Add in a drawback section
  • Improve the industrial application section
  • Second paragraph of the section “industrial applications” doesn’t really belong there, it would fit better in the tunability section
  • No reference in paragraph 3 of the same section
  • Could add more information about supported ionic liquid phases, which is briefly mentioned in the very last page, which says these are a potential solution to this problem but don’t mention WHY or HOW.
  • The whole article only has 7 references, not nearly enough.
  • Could add a section about regeneration energy requirements
  • Could add in a history section of past applications

Articles Found by TK

  • I found an interesting project involving phase changing ionic liquids for CO2 capture. It is a research project running 2015-2018 at the University of Notre Dame. An interesting part of this report is that it goes into an alternative solution to overcoming the high viscosity of ionic liquids. This could be added in after a drawback section.
    • https://www.osti.gov/scitech/servlets/purl/1046730 [project overview]
    • https://www.osti.gov/scitech/servlets/purl/1337563 [technical report]
  • Another interesting project was done by the Georgia Tech research Corporation in a project published in 2011. They developed reversible ionic liquids (RevILs) that offer a high absorption capacity. These have reduced viscosity due to the addition of Si in the molecules. They claim to have designed a RevIL which requires only a 3rd of the energy as a typical 90% CO2 capture process by MEA.
    • https://www.osti.gov/scitech/servlets/purl/1084025 [final report]
  • Some commercial applications and costs for producing different grades of CO2 from amines are presented in this 2007 paper. http://science.sciencemag.org/content/sci/325/5948/1652.full.pdf
    • http://ac.els-cdn.com/S0196890496002713/1-s2.0-S0196890496002713-main.pdf?_tid=5a2b0826-239f-11e7-a219-00000aacb361&acdnat=1492455477_4a2f912b8da15261dda4a4dc92d55f6e [review of CO2 disposal in Texas]
    • http://ac.els-cdn.com/019689049290028U/1-s2.0-019689049290028U-main.pdf?_tid=38dc5648-239f-11e7-aca6-00000aacb361&acdnat=1492455422_6f8581da3ec548244c948777230c02c5 [description of process used commercially in Texas on coal fired power plants]

Thoughts from TK

I think we can do a couple of things from the 5 references I found.

  • Add in a drawback section talking about the high regeneration costs of amine systems and the problem with high viscosity
    • We could then add in descriptions of the current research being done to overcome this problem
  • Add in a commercial application example section and talk about the systems used in Texas that use MEA based approach. There are detailed cost estimates of those plants. Not sure what the current status is of those though, those references are from 1990s-2007

GR

  • Background/mechanism of how separation works with ionic liquids as the solvent: http://pubs.rsc.org/en/content/articlelanding/2016/fd/c6fd00081a#!divAbstract
  • Different types of ionic liquids and/or a list of examples: http://pubs.rsc.org/en/content/articlepdf/2012/ee/c2ee21152a
  • Both of the above: http://pubs.acs.org/doi/pdf/10.1021/ie3003705
  • Ideas of sections/content to add
    • A brief “mechanism” section to explain how ionic liquids function as carbon capture solvents
    • An “examples” section where we mention the different categories of ionic liquids and list examples under each. The second two articles I linked sort of do this.

JS

  • Suggestion: Add brief intro to ionic liquids with link to main article
  • Suggestion: Add comparisons of ionic liquids vs amines etc in terms of ccs potential (general comparison + graph of solubility of CO2 in specific ILs and amines)
  • Suggestion: Add examples of environmentally friendliness of ILs vs amines/current solvents to industrial applications section
  • Suggestion: Add a “Current Developments” section to list the progress of research in ILs for CCS

Some articles:

Review of pre-combustion capture and ionic liquid in carbon capture

and storage.

http://www.sciencedirect.com/science/article/pii/S0306261916314052

Carbon dioxide absorption into promoted potassium carbonate solutions: A review

http://ac.els-cdn.com/S1750583616303838/1-s2.0-S1750583616303838-main.pdf?_tid=9355e280-1fbf-11e7-89b2-00000aacb362&acdnat=1492029513_24712224b2fb9abe86c9fe25291feb8f

JJ

In this review the authors analyze the chemical absorption process in ionic liquids. They also review different IL´s mass transfer parameter. It's a good paper if we want to add more background to the wikipedia page.

http://eds.b.ebscohost.com/ehost/pdfviewer/pdfviewer?sid=ec518047-be9e-4408-bbca-f637d9235c0b%40sessionmgr103&vid=1&hid=126

The next paper describes a new material using a supported LI phase. This material consisting in aminofunctionalized-IL droplets within envelopes of silica nanoparticles, can operate between 30 and 60°C. Is a novel material for “dry” carbon capture.

https://sci-hub.cc/10.1021/jp5062946 CO2 Capture by Novel Supported Ionic Liquid Phase Systems Consisting of Silica Nanoparticles Encapsulating AmineFunctionalized Ionic Liquids

This review analyze the history of the LI development for carbon capture focusing on the chemical properties and structural design. Its a brief paper that we can use to support the introduction and show some strategies in the synthesis of new materials, in this case IL.

http://www.sciencedirect.com/science/article/pii/S2452223616300621

Possible Articles to Edit (12 Apr, 2017)

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  • Slash and char
  • Carbon dioxide Scrubber (For the amine section and the activated carbon section)
  • Oxycombustion
  • Molten Carbonate Fuel Cells
  • Ionic Liquids in Carbon Capture
    • https://en.wikipedia.org/wiki/Ionic_liquids_in_carbon_capture
    • Articles
      • Review of pre-combustion capture and ionic liquid in carbon capture
      • and storage.
        • http://www.sciencedirect.com/science/article/pii/S0306261916314052
      • Solvents for CO2 Capture (physical solvents -- including ionic liquids)
        • https://www.netl.doe.gov/File%20Library/research/coal/carbon%20capture/R-D048.pdf
      • Carbon dioxide absorption into promoted potassium carbonate solutions: A review
        • http://ac.els-cdn.com/S1750583616303838/1-s2.0-S1750583616303838-main.pdf?_tid=9355e280-1fbf-11e7-89b2-00000aacb362&acdnat=1492029513_24712224b2fb9abe86c9fe25291feb8f
  • Carbon Capture and Storage#Environmental Effects
    • https://en.wikipedia.org/wiki/Carbon_capture_and_storage#Environmental_effects
    • Articles
    • Environmental Impacts of Carbon Capture, Transmission, Enhanced Oil Recovery, and Sequestration: An Overview.
      • http://eds.a.ebscohost.com.pbidi.unam.mx:8080/ehost/detail/detail?sid=fedb2c53-5814-4b20-a87b-3263fed47f3a%40sessionmgr4006&vid=0&hid=4211&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#AN=92562448&db=eih
    • A Technical, Economic, and Environmental Assessment of Amine-Based CO2 Capture Technology for Power Plant Greenhouse Gas Control
      • http://pubs.acs.org/doi/abs/10.1021/es0158861
    • An initial assessment of the potential environmental impact of CO2 escape from marine carbon capture and storage systems
      • http://journals.sagepub.com/doi/abs/10.1243/09576509jpe623

References

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  1. ^ Earle, Martyn J.; Esperança, José M.S.S.; Gilea, Manuela A.; Lopes, José N. Canongia; Rebelo, Luís P.N.; Magee, Joseph W.; Seddon, Kenneth R.; Widegren, Jason A. "The distillation and volatility of ionic liquids". Nature. 439 (7078): 831–834. doi:10.1038/nature04451.
  2. ^ Endres, Frank; Abedin, Sherif Zein El (2006-05-03). "Air and water stable ionic liquids in physical chemistry". Physical Chemistry Chemical Physics. 8 (18). doi:10.1039/B600519P. ISSN 1463-9084.
  3. ^ Dake, Satish A.; Kulkarni, Ravibhushan S.; Kadam, Vijay N.; Modani, Sandesh S.; Bhale, Jayant J.; Tathe, Sumangala B.; Pawar, Rajendra P. (2009-10-12). "Phosphonium Ionic Liquid: A Novel Catalyst for Benzyl Halide Oxidation". Synthetic Communications. 39 (21): 3898–3904. doi:10.1080/00397910902840835. ISSN 0039-7911.
  4. ^ Ngo, Helen L; LeCompte, Karen; Hargens, Liesl; McEwen, Alan B (2000-08-14). "Thermal properties of imidazolium ionic liquids". Thermochimica Acta. 357–358: 97–102. doi:10.1016/S0040-6031(00)00373-7.
  5. ^ Endres, Frank; Abedin, Sherif Zein El (2006-05-03). "Air and water stable ionic liquids in physical chemistry". Physical Chemistry Chemical Physics. 8 (18). doi:10.1039/B600519P. ISSN 1463-9084.
  6. ^ a b Bradaric, Christine J.; Downard, Andrew; Kennedy, Christine; Robertson, Allan J.; Zhou, Yuehui (2003-04-08). "Industrial preparation of phosphonium ionic liquidsPortions of this work were presented at the following meetings: (a) 224th American Chemical Society Conference, Boston, USA, 2002; (b) Green Solvents for Catalysis Meeting, held in Bruchsal, Germany, 13–16th October 2002". Green Chemistry. 5 (2): 143–152. doi:10.1039/b209734f. ISSN 1463-9270.
  7. ^ Valencia-Marquez, Darinel; Flores-Tlacuahuac, Antonio; Ricardez-Sandoval, Luis (2015-11-18). "Technoeconomic and Dynamical Analysis of a CO2 Capture Pilot-Scale Plant Using Ionic Liquids". Industrial & Engineering Chemistry Research. 54 (45): 11360–11370. doi:10.1021/acs.iecr.5b02544. ISSN 0888-5885.
  8. ^ Zhao, Hua; Xia, Shuqian; Ma, Peisheng (1 October 2005). "Use of ionic liquids as 'green' solvents for extractions". Journal of Chemical Technology & Biotechnology. pp. 1089–1096. doi:10.1002/jctb.1333.
  9. ^ Bara, Jason E.; Camper, Dean E.; Gin, Douglas L.; Noble, Richard D. (19 January 2010). "Room-Temperature Ionic Liquids and Composite Materials: Platform Technologies for CO2 Capture". Accounts of Chemical Research. pp. 152–159. doi:10.1021/ar9001747.
  10. ^ Blanchard, Lynnette A.; Hancu, Dan; Beckman, Eric J.; Brennecke, Joan F. "Green processing using ionic liquids and CO2". Nature. 399 (6731): 28–29. doi:10.1038/19887.
  11. ^ a b Earle, Martyn J.; Seddon, Kenneth R. (2000-01-01). "Ionic liquids. Green solvents for the future". Pure and Applied Chemistry. 72 (7). doi:10.1351/pac200072071391. ISSN 1365-3075.
  12. ^ Welton, Thomas (11 August 1999). [pubs.acs.org/doi/abs/10.1021/cr980032t "Room-Temperature Ionic Liquids. Solvents for Synthesis and Catalysis"]. Chemical Reviews. pp. 2071–2084. doi:10.1021/cr980032t. {{cite web}}: Check |url= value (help)
  13. ^ Ghandi, Khashayar. "A Review of Ionic Liquids, Their Limits and Applications". Green and Sustainable Chemistry. 04 (01): 44–53. doi:10.4236/gsc.2014.41008.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  14. ^ Armand, Michel; Endres, Frank; MacFarlane, Douglas R.; Ohno, Hiroyuki; Scrosati, Bruno. "Ionic-liquid materials for the electrochemical challenges of the future". Nature Materials. 8 (8): 621–629. doi:10.1038/nmat2448.
  15. ^ Guerfi, A.; Dontigny, M.; Charest, P.; Petitclerc, M.; Lagacé, M.; Vijh, A.; Zaghib, K. (2010-02-01). "Improved electrolytes for Li-ion batteries: Mixtures of ionic liquid and organic electrolyte with enhanced safety and electrochemical performance". Journal of Power Sources. 195 (3): 845–852. doi:10.1016/j.jpowsour.2009.08.056.
  16. ^ Lewandowski, Andrzej; Świderska-Mocek, Agnieszka (2009-12-01). "Ionic liquids as electrolytes for Li-ion batteries—An overview of electrochemical studies". Journal of Power Sources. 194 (2): 601–609. doi:10.1016/j.jpowsour.2009.06.089.
  17. ^ Weingarth, Daniel; Czekaj, Izabela; Fei, Zhaofu; Foelske-Schmitz, Annette; Dyson, Paul J.; Wokaun, Alexander; Kötz, Rüdiger (2012-01-01). "Electrochemical Stability of Imidazolium Based Ionic Liquids Containing Cyano Groups in the Anion: A Cyclic Voltammetry, XPS and DFT Study". Journal of The Electrochemical Society. 159 (7): H611–H615. doi:10.1149/2.001207jes. ISSN 0013-4651.
  18. ^ Wang, Congmin; Luo, Huimin; Luo, Xiaoyan; Li, Haoran; Dai, Sheng (2010-11-03). "Equimolar CO2 capture by imidazolium-based ionic liquids and superbase systems". Green Chemistry. 12 (11). doi:10.1039/c0gc00070a. ISSN 1463-9270.
  19. ^ Yu, Jeong-In; Ju, Hye-Young; Kim, Kyung-Hoon; Park, Dae-Won (2010-03-01). "Cycloaddition of carbon dioxide to butyl glycidyl ether using imidazolium salt ionic liquid as a catalyst". Korean Journal of Chemical Engineering. 27 (2): 446–451. doi:10.1007/s11814-010-0074-1. ISSN 0256-1115.
  20. ^ Dake, Satish A.; Kulkarni, Ravibhushan S.; Kadam, Vijay N.; Modani, Sandesh S.; Bhale, Jayant J.; Tathe, Sumangala B.; Pawar, Rajendra P. (2009-10-12). "Phosphonium Ionic Liquid: A Novel Catalyst for Benzyl Halide Oxidation". Synthetic Communications. 39 (21): 3898–3904. doi:10.1080/00397910902840835. ISSN 0039-7911.
  21. ^ Harper, Naomi D.; Nizio, Katie D.; Hendsbee, Arthur D.; Masuda, Jason D.; Robertson, Katherine N.; Murphy, Luke J.; Johnson, Michel B.; Pye, Cory C.; Clyburne, Jason A. C. (2011-03-02). "Survey of Carbon Dioxide Capture in Phosphonium-Based Ionic Liquids and End-Capped Polyethylene Glycol Using DETA (DETA = Diethylenetriamine) as a Model Absorbent". Industrial & Engineering Chemistry Research. 50 (5): 2822–2830. doi:10.1021/ie101734h. ISSN 0888-5885.
  22. ^ Hajipour, Abdol R.; Seddighi, Mohadeseh (2012-01-15). "Pyridinium-Based Brønsted Acidic Ionic Liquid as a Highly Efficient Catalyst for One-Pot Synthesis of Dihydropyrimidinones". Synthetic Communications. 42 (2): 227–235. doi:10.1080/00397911.2010.523488. ISSN 0039-7911.
  23. ^ Pajuste, Karlis; Plotniece, Aiva; Kore, Kintija; Intenberga, Liva; Cekavicus, Brigita; Kaldre, Dainis; Duburs, Gunars; Sobolev, Arkadij (2011-02-01). "Use of pyridinium ionic liquids as catalysts for the synthesis of 3,5-bis(dodecyloxycarbonyl)-1,4-dihydropyridine derivative". Open Chemistry. 9 (1). doi:10.2478/s11532-010-0132-x. ISSN 2391-5420.
  24. ^ Tsunashima, Katsuhiko; Kawabata, Atsuko; Matsumiya, Masahiko; Kodama, Shun; Enomoto, Ryuichi; Sugiya, Masashi; Kunugi, Yoshihito (2011-02-01). "Low viscous and highly conductive phosphonium ionic liquids based on bis(fluorosulfonyl)amide anion as potential electrolytes". Electrochemistry Communications. 13 (2): 178–181. doi:10.1016/j.elecom.2010.12.007.