On the way to greener ionic liquids: Identification of a fully mineralizable phenylalanine-based ionic liquid

Research output: Journal contributionsJournal articlesResearchpeer-review

Authors

Over the past few decades ionic liquids (ILs) are increasingly seen as an important building block of green chemistry because of their specific properties as solvents, such as their potential for high recyclability, low volatility, low flammability, low toxicity, and their potential for synthesis from renewable resources. However, avoiding persistent or toxic cation/anion fragments is also urgently needed. In the best case they should be fully mineralizable by microorganisms after their release into the aquatic environment. The fragments fostering this can be determined by biodegradation studies, and the employment of identified readily biodegradable building blocks presents an innovation in the targeted design of green environmentally friendly ILs. The aim of this study was to improve the data-platform for the design of completely mineralizable ILs. Therefore the ready biodegradability of seven phenylalanine-based ILs and three non-ionic related compounds was investigated with a modified Closed Bottle test based on OECD guideline 301D. Liquid chromatography combined with high-resolution mass spectrometry (LC-HRMS) analysis was used to identify the chemical structures of products resulting from incomplete biodegradation and transformation. Two kinds of degradation pathways were observed: the hydrolysis of an ethyl ester group or the hydrolysis of an amide bond and biodegradation of the released phenylalanine ethyl ester. Both degradation pathways resulted in persistent transformation products (TPs) with the exception of IL (4), a pyridinium substituted phenylalanine derived IL and the non-ionic deanol derivative (2a). IL (4) was ultimately biodegraded in the CBT after 42 days without leaving any TP. The biodegradation of compound (2a) was 78% after 42 days but resulted in a TP, which was readily biodegradable in a further CBT after a lag phase of 3 weeks, respectively. Even if both compounds were not "readily biodegradable" in the sense of the OECD guideline, particularly IL (4) can be proposed as a basic structure for sustainable and green ILs (benign by design) with the aim of optimizing its degradation rate further.

Original languageEnglish
JournalGreen Chemistry
Volume18
Issue number16
Pages (from-to)4361-4373
Number of pages13
ISSN1463-9262
DOIs
Publication statusPublished - 2016

DOI

Recently viewed

Publications

  1. Chapter 9: Particular Remedies for Non-performance: Section 5: Damages and Interest
  2. Links between RCEs and Higher Education Institutions
  3. Schulleitungsmonitor Schweiz 2022
  4. An Im(Possible) Program
  5. Common Ground and Development
  6. Anmerkung zu EuGH Rs. C-555/07 (Kücükdeveci)
  7. Spatial scaling of extinction rates
  8. Governance im Wandel
  9. Oder/Denken
  10. Seth Price. Decimating Digital Data
  11. Medienpolitik in der EU
  12. The Welcomers
  13. Gods of tomorrow?
  14. Das fossile Imperium schlägt zurück
  15. Qualitätsentwicklung und Qualitätssicherung in der Schreibzentrumsarbeit
  16. Medizinische Forschung an Kindern
  17. Special issue: Exports, imports, and productivity at the firm level
  18. Mountain roads and non-native species modify elevational patterns of plant diversity
  19. Anders als die anderen?
  20. Selbstbestimmung und Classroom-Management
  21. Reduction of Atmospheric Transboundary Fluxes of Heavy Metals in Europe
  22. Pragmatism, Truth and Social Accounting Research
  23. LehrerInnen als "Reflective Practitioner"
  24. Learning from Co-Founders of Grassroots Initiatives
  25. Web-based depression treatment
  26. Linkshändigkeit als Privileg oder Nachteil bei Notebookeingabegeräten?
  27. Feldstudie zur Entwicklung der Rechenfertigkeit von Erstklässlern.
  28. Global, lokal, digital
  29. Moralphilosophische Fragen zum "Embryo"
  30. Was tun?
  31. Finance is Society!
  32. Part 14 Control of political donations and expenditure
  33. Corporate Governance Reporting zum Prüfungsausschuss
  34. Wunsch und Technik
  35. Critical Reflections on "Democracy in Crisis'
  36. Moirés, Andreas Fogarasi, Katya Sander, Urtica
  37. Global, lokal, digital
  38. Merkmale des SEMIK-Schwerpunkts "Entwicklung von Unterrichtskonzepten"