Thermal resilience of imidazolium-based ionic liquids-studies on short- and long-term thermal stability and decomposition mechanism of 1-Alkyl-3-methylimidazolium halides by thermal analysis and single-photon ionization time-of-flight mass spectrometry.
J. Phys. Chem. B 122, 8738-8749 (2018)
Ionic liquids are often considered as green alternatives of volatile organic solvents. The thermal behavior of the ionic liquids is relevant for a number of emerging large-scale applications at elevated temperature. Knowledge about the degradation products is indispensable for treatment and recycling of the used ionic liquids. The objective of this paper was an investigation of the short- and long-term stability of several 1-alkyl-3-methylimidazolium halides, determination of the degradation products, and the elucidation of their decomposition patterns and structure-stability relations. Short-term stability and mechanism of thermal degradation were investigated by a self-developed, innovative thermal analysis single-photon ionization timeof-flight mass spectrometry device with Skimmer coupling. The applied technology provides real-time monitoring of the forming species and allows tracing their change during the course of the decomposition. Therein, the almost fragment-free soft ionization with vacuum ultraviolet photons plays a crucial role. We have detected unfragmented molecules whose formation was only assumed by electron ionization. Nevertheless, the main decomposition products of the selected ionic liquids were alkyl imidazoles, alkenes, alkyl halides, and hydrogen halides. From the decomposition products, we have deduced the fragmentation patterns and discussed their interrelation with the length of the alkyl chain and the type of the halide anion. Our results did not suggest the evaporation of the investigated ionic liquids prior to their decomposition under atmospheric conditions. Long-term thermal stability and applicability were determined based on thermogravimetric analysis evaluated with a kinetic model. Thus, the time-dependent maximum operation temperature (MOT) for the respective ionic liquids has been calculated. As a rule, the short-term stability overestimates the long-term decomposition temperatures; the calculated MOT are significantly lower (at least 100 K) than the standardly obtained decomposition temperatures.
Impact Factor
Scopus SNIP
Web of Science
Times Cited
Scopus
Cited By
Altmetric
Publikationstyp
Artikel: Journalartikel
Dokumenttyp
Wissenschaftlicher Artikel
Typ der Hochschulschrift
Herausgeber
Schlagwörter
Evolved Gas-analysis; Tribological Performance; Stationary Phases; Crude Oils; Tga-ms; Cellulose; Solvents; Thermogravimetry; Chromatography; Lubricants
Keywords plus
Sprache
Veröffentlichungsjahr
2018
Prepublished im Jahr
HGF-Berichtsjahr
2018
ISSN (print) / ISBN
1520-6106
e-ISSN
1520-5207
ISBN
Bandtitel
Konferenztitel
Konferzenzdatum
Konferenzort
Konferenzband
Quellenangaben
Band: 122,
Heft: 37,
Seiten: 8738-8749
Artikelnummer: ,
Supplement: ,
Reihe
Verlag
American Chemical Society (ACS)
Verlagsort
1155 16th St, Nw, Washington, Dc 20036 Usa
Tag d. mündl. Prüfung
0000-00-00
Betreuer
Gutachter
Prüfer
Topic
Hochschule
Hochschulort
Fakultät
Veröffentlichungsdatum
0000-00-00
Anmeldedatum
0000-00-00
Anmelder/Inhaber
weitere Inhaber
Anmeldeland
Priorität
Begutachtungsstatus
Peer reviewed
POF Topic(s)
30202 - Environmental Health
30504 - Mechanisms of Genetic and Environmental Influences on Health and Disease
Forschungsfeld(er)
Environmental Sciences
Radiation Sciences
PSP-Element(e)
G-504500-001
G-501100-008
Förderungen
Copyright
Erfassungsdatum
2018-10-01