---
_id: '13671'
abstract:
- lang: eng
  text: The aging of biodiesel proceeds via multiple pathways, with oligomerization
    playing a central role. In this study, we investigated an epoxide-dependent oligomerization
    pathway, which had previously only been postulated. Using methyl oleate (C18:1)
    as a model monounsaturated fatty acid and acetic acid as a representative, reactive
    nucleophile and known biodiesel aging product with a suitable boiling point, oligomeric
    products were identified by size-exclusion chromatography (SEC) coupled with electrospray
    ionization quadrupole time-of-flight mass spectrometry (ESI-QTOF-MS). The concentration
    of 20 wt% was chosen to ensure a measurable kinetic effect while maintaining stable
    reaction conditions. Furthermore, the role of methyl oleate during biodiesel aging
    was addressed. Time-resolved analysis confirmed the proposed sequential order
    of reactions. It was pointed out that elimination reactions may occur. The data
    support the formation of epoxides, despite the isobaric overlap with ketones,
    and show that hydroxyl intermediates undergo esterification and etherification.
    Moreover, experiments with pure C18:1 demonstrated that acetic acid–derived oligomers
    are generated. Under Rancimat conditions, addition of 20 wt% acetic acid resulted
    in an approximately 1.1 – 2.6 increase in product yield. Kinetic analysis revealed
    structure-dependent formation and decay behavior of the aging products, with slightly
    faster epoxidation and shifted product distributions toward higher oligomeric
    species in the presence of acetic acid. Reactive intermediates were consumed more
    rapidly than oligomeric species and all decay processes followed apparent second-order
    kinetics. These findings provide direct experimental evidence for the involvement
    of epoxide-dependent pathways in biodiesel aging.
article_number: '139339'
author:
- first_name: Julian
  full_name: Türck, Julian
  last_name: Türck
- first_name: Carsten
  full_name: Funke, Carsten
  id: '74167'
  last_name: Funke
- first_name: Fabian
  full_name: Schmitt, Fabian
  last_name: Schmitt
- first_name: Jan
  full_name: Schneider, Jan
  id: '13209'
  last_name: Schneider
  orcid: 0000-0001-6401-8873
- first_name: Hans-Jürgen
  full_name: Danneel, Hans-Jürgen
  id: '12231'
  last_name: Danneel
- first_name: Ralf
  full_name: Türck, Ralf
  last_name: Türck
- first_name: Wolfgang
  full_name: Ruck, Wolfgang
  last_name: Ruck
- first_name: Jürgen
  full_name: Krahl, Jürgen
  id: '68870'
  last_name: Krahl
citation:
  ama: 'Türck J, Funke C, Schmitt F, et al. Kinetic study and confirmation of epoxide-dependent
    oligomerization of methyl oleate. <i>Fuel : the science and technology of fuel
    and energy </i>. 2026;424. doi:<a href="https://doi.org/10.1016/j.fuel.2026.139339">10.1016/j.fuel.2026.139339</a>'
  apa: 'Türck, J., Funke, C., Schmitt, F., Schneider, J., Danneel, H.-J., Türck, R.,
    Ruck, W., &#38; Krahl, J. (2026). Kinetic study and confirmation of epoxide-dependent
    oligomerization of methyl oleate. <i>Fuel : The Science and Technology of Fuel
    and Energy </i>, <i>424</i>, Article 139339. <a href="https://doi.org/10.1016/j.fuel.2026.139339">https://doi.org/10.1016/j.fuel.2026.139339</a>'
  bjps: '<b>Türck J <i>et al.</i></b> (2026) Kinetic Study and Confirmation of Epoxide-Dependent
    Oligomerization of Methyl Oleate. <i>Fuel : the science and technology of fuel
    and energy </i> <b>424</b>.'
  chicago: 'Türck, Julian, Carsten Funke, Fabian Schmitt, Jan Schneider, Hans-Jürgen
    Danneel, Ralf Türck, Wolfgang Ruck, and Jürgen Krahl. “Kinetic Study and Confirmation
    of Epoxide-Dependent Oligomerization of Methyl Oleate.” <i>Fuel : The Science
    and Technology of Fuel and Energy </i> 424 (2026). <a href="https://doi.org/10.1016/j.fuel.2026.139339">https://doi.org/10.1016/j.fuel.2026.139339</a>.'
  chicago-de: 'Türck, Julian, Carsten Funke, Fabian Schmitt, Jan Schneider, Hans-Jürgen
    Danneel, Ralf Türck, Wolfgang Ruck und Jürgen Krahl. 2026. Kinetic study and confirmation
    of epoxide-dependent oligomerization of methyl oleate. <i>Fuel : the science and
    technology of fuel and energy </i> 424. doi:<a href="https://doi.org/10.1016/j.fuel.2026.139339">10.1016/j.fuel.2026.139339</a>,
    .'
  din1505-2-1: '<span style="font-variant:small-caps;">Türck, Julian</span> ; <span
    style="font-variant:small-caps;">Funke, Carsten</span> ; <span style="font-variant:small-caps;">Schmitt,
    Fabian</span> ; <span style="font-variant:small-caps;">Schneider, Jan</span> ;
    <span style="font-variant:small-caps;">Danneel, Hans-Jürgen</span> ; <span style="font-variant:small-caps;">Türck,
    Ralf</span> ; <span style="font-variant:small-caps;">Ruck, Wolfgang</span> ; <span
    style="font-variant:small-caps;">Krahl, Jürgen</span>: Kinetic study and confirmation
    of epoxide-dependent oligomerization of methyl oleate. In: <i>Fuel : the science
    and technology of fuel and energy </i> Bd. 424. Amsterdam [u.a.], Elsevier (2026)'
  havard: 'J. Türck, C. Funke, F. Schmitt, J. Schneider, H.-J. Danneel, R. Türck,
    W. Ruck, J. Krahl, Kinetic study and confirmation of epoxide-dependent oligomerization
    of methyl oleate, Fuel : The Science and Technology of Fuel and Energy . 424 (2026).'
  ieee: 'J. Türck <i>et al.</i>, “Kinetic study and confirmation of epoxide-dependent
    oligomerization of methyl oleate,” <i>Fuel : the science and technology of fuel
    and energy </i>, vol. 424, Art. no. 139339, 2026, doi: <a href="https://doi.org/10.1016/j.fuel.2026.139339">10.1016/j.fuel.2026.139339</a>.'
  mla: 'Türck, Julian, et al. “Kinetic Study and Confirmation of Epoxide-Dependent
    Oligomerization of Methyl Oleate.” <i>Fuel : The Science and Technology of Fuel
    and Energy </i>, vol. 424, 139339, 2026, <a href="https://doi.org/10.1016/j.fuel.2026.139339">https://doi.org/10.1016/j.fuel.2026.139339</a>.'
  short: 'J. Türck, C. Funke, F. Schmitt, J. Schneider, H.-J. Danneel, R. Türck, W.
    Ruck, J. Krahl, Fuel : The Science and Technology of Fuel and Energy  424 (2026).'
  ufg: '<b>Türck, Julian u. a.</b>: Kinetic study and confirmation of epoxide-dependent
    oligomerization of methyl oleate, in: <i>Fuel : the science and technology of
    fuel and energy </i> 424 (2026).'
  van: 'Türck J, Funke C, Schmitt F, Schneider J, Danneel HJ, Türck R, et al. Kinetic
    study and confirmation of epoxide-dependent oligomerization of methyl oleate.
    Fuel : the science and technology of fuel and energy . 2026;424.'
date_created: 2026-04-07T12:49:23Z
date_updated: 2026-04-08T12:55:00Z
doi: 10.1016/j.fuel.2026.139339
intvolume: '       424'
keyword:
- Biodiesel aging
- Epoxide-dependent oligomerization
- Acetic acid
- Identification of aging products
- Kinetics of aging products
language:
- iso: eng
place: Amsterdam [u.a.]
publication: 'Fuel : the science and technology of fuel and energy '
publication_identifier:
  eissn:
  - 1873-7153
  issn:
  - 0016-2361
publication_status: published
publisher: Elsevier
quality_controlled: '1'
status: public
title: Kinetic study and confirmation of epoxide-dependent oligomerization of methyl
  oleate
type: scientific_journal_article
user_id: '83781'
volume: 424
year: '2026'
...
---
_id: '12823'
abstract:
- lang: eng
  text: The energy crisis and dependence on fossil fuels forces societies to develop
    alternative pathways to secure energy supplies. Therefore, non‐fossil fuels such
    as biofuels and e‐fuels can help counteract the resulting demand for existing
    combustion engines. However, biofuels, like biodiesel, have disadvantages in terms
    of oxidation stability. In general, aging of biodiesel is a complex mechanism
    due to interaction of various components. In order to develop an ideal fuel, the
    mechanism must be understood in full detail. In this work, an attempt is made
    to simplify the system by using methyl oleate as a biodiesel model component.
    In addition, other fuel components of interest such as alcohols and their respective
    acids help to clarify the aging mechanism. This work used isopropylidene glycerol
    (solketal) as the main alcohol, 1‐octanol and octanoic acid. A holistic biodiesel
    aging scheme was developed by using generated data and evaluating the role of
    acids. They epoxidize unsaturated fatty acid via Prileschajev reactions. In addition,
    the role of epoxides in oligomerization reactions is confirmed. Moreover, the
    alcohols show that the suppression of oligomerization can be achieved by the reaction
    with methyl oleate. The alcohol‐dependent aging products were determined by quadrupole
    time‐of‐flight (Q‐TOF) mass spectrometry.
author:
- first_name: Julian
  full_name: Türck, Julian
  last_name: Türck
- first_name: Fabian
  full_name: Schmitt, Fabian
  last_name: Schmitt
- first_name: Lukas
  full_name: Anthofer, Lukas
  last_name: Anthofer
- first_name: Ralf
  full_name: Türck, Ralf
  last_name: Türck
- first_name: Wolfgang
  full_name: Ruck, Wolfgang
  last_name: Ruck
- first_name: Jürgen
  full_name: Krahl, Jürgen
  id: '68870'
  last_name: Krahl
citation:
  ama: 'Türck J, Schmitt F, Anthofer L, Türck R, Ruck W, Krahl J. Extension of Biodiesel
    Aging Mechanism–the Role and Influence of Methyl Oleate and the Contribution of
    Alcohols Through the Use of Solketal. <i>  ChemSusChem : chemistry &#38; sustainability,
    energy &#38; materials</i>. 2023;16(17). doi:<a href="https://doi.org/10.1002/cssc.202300263">10.1002/cssc.202300263</a>'
  apa: 'Türck, J., Schmitt, F., Anthofer, L., Türck, R., Ruck, W., &#38; Krahl, J.
    (2023). Extension of Biodiesel Aging Mechanism–the Role and Influence of Methyl
    Oleate and the Contribution of Alcohols Through the Use of Solketal. <i>  ChemSusChem :
    Chemistry &#38; Sustainability, Energy &#38; Materials</i>, <i>16</i>(17). <a
    href="https://doi.org/10.1002/cssc.202300263">https://doi.org/10.1002/cssc.202300263</a>'
  bjps: '<b>Türck J <i>et al.</i></b> (2023) Extension of Biodiesel Aging Mechanism–the
    Role and Influence of Methyl Oleate and the Contribution of Alcohols Through the
    Use of Solketal. <i>  ChemSusChem : chemistry &#38; sustainability, energy &#38;
    materials</i> <b>16</b>.'
  chicago: 'Türck, Julian, Fabian Schmitt, Lukas Anthofer, Ralf Türck, Wolfgang Ruck,
    and Jürgen Krahl. “Extension of Biodiesel Aging Mechanism–the Role and Influence
    of Methyl Oleate and the Contribution of Alcohols Through the Use of Solketal.”
    <i>  ChemSusChem : Chemistry &#38; Sustainability, Energy &#38; Materials</i>
    16, no. 17 (2023). <a href="https://doi.org/10.1002/cssc.202300263">https://doi.org/10.1002/cssc.202300263</a>.'
  chicago-de: 'Türck, Julian, Fabian Schmitt, Lukas Anthofer, Ralf Türck, Wolfgang
    Ruck und Jürgen Krahl. 2023. Extension of Biodiesel Aging Mechanism–the Role and
    Influence of Methyl Oleate and the Contribution of Alcohols Through the Use of
    Solketal. <i>  ChemSusChem : chemistry &#38; sustainability, energy &#38; materials</i>
    16, Nr. 17. doi:<a href="https://doi.org/10.1002/cssc.202300263">10.1002/cssc.202300263</a>,
    .'
  din1505-2-1: '<span style="font-variant:small-caps;">Türck, Julian</span> ; <span
    style="font-variant:small-caps;">Schmitt, Fabian</span> ; <span style="font-variant:small-caps;">Anthofer,
    Lukas</span> ; <span style="font-variant:small-caps;">Türck, Ralf</span> ; <span
    style="font-variant:small-caps;">Ruck, Wolfgang</span> ; <span style="font-variant:small-caps;">Krahl,
    Jürgen</span>: Extension of Biodiesel Aging Mechanism–the Role and Influence of
    Methyl Oleate and the Contribution of Alcohols Through the Use of Solketal. In:
    <i>  ChemSusChem : chemistry &#38; sustainability, energy &#38; materials</i>
    Bd. 16. Weinheim, Wiley (2023), Nr. 17'
  havard: 'J. Türck, F. Schmitt, L. Anthofer, R. Türck, W. Ruck, J. Krahl, Extension
    of Biodiesel Aging Mechanism–the Role and Influence of Methyl Oleate and the Contribution
    of Alcohols Through the Use of Solketal,   ChemSusChem : Chemistry &#38; Sustainability,
    Energy &#38; Materials. 16 (2023).'
  ieee: 'J. Türck, F. Schmitt, L. Anthofer, R. Türck, W. Ruck, and J. Krahl, “Extension
    of Biodiesel Aging Mechanism–the Role and Influence of Methyl Oleate and the Contribution
    of Alcohols Through the Use of Solketal,” <i>  ChemSusChem : chemistry &#38; sustainability,
    energy &#38; materials</i>, vol. 16, no. 17, 2023, doi: <a href="https://doi.org/10.1002/cssc.202300263">10.1002/cssc.202300263</a>.'
  mla: 'Türck, Julian, et al. “Extension of Biodiesel Aging Mechanism–the Role and
    Influence of Methyl Oleate and the Contribution of Alcohols Through the Use of
    Solketal.” <i>  ChemSusChem : Chemistry &#38; Sustainability, Energy &#38; Materials</i>,
    vol. 16, no. 17, 2023, <a href="https://doi.org/10.1002/cssc.202300263">https://doi.org/10.1002/cssc.202300263</a>.'
  short: 'J. Türck, F. Schmitt, L. Anthofer, R. Türck, W. Ruck, J. Krahl,   ChemSusChem :
    Chemistry &#38; Sustainability, Energy &#38; Materials 16 (2023).'
  ufg: '<b>Türck, Julian u. a.</b>: Extension of Biodiesel Aging Mechanism–the Role
    and Influence of Methyl Oleate and the Contribution of Alcohols Through the Use
    of Solketal, in: <i>  ChemSusChem : chemistry &#38; sustainability, energy &#38;
    materials</i> 16 (2023), H. 17.'
  van: 'Türck J, Schmitt F, Anthofer L, Türck R, Ruck W, Krahl J. Extension of Biodiesel
    Aging Mechanism–the Role and Influence of Methyl Oleate and the Contribution of
    Alcohols Through the Use of Solketal.   ChemSusChem : chemistry &#38; sustainability,
    energy &#38; materials. 2023;16(17).'
date_created: 2025-04-22T13:38:51Z
date_updated: 2025-06-26T07:47:02Z
department:
- _id: DEP1408
doi: 10.1002/cssc.202300263
external_id:
  isi:
  - '001025502300001'
  pmid:
  - '37220243'
intvolume: '        16'
isi: '1'
issue: '17'
keyword:
- biodiesel aging
- epoxide-dependent oligomerization
- solketal
- Prileschajew reaction
language:
- iso: eng
place: Weinheim
pmid: '1'
publication: '  ChemSusChem : chemistry & sustainability, energy & materials'
publication_identifier:
  eissn:
  - 1864-564X
  issn:
  - 1864-5631
publication_status: published
publisher: Wiley
status: public
title: Extension of Biodiesel Aging Mechanism–the Role and Influence of Methyl Oleate
  and the Contribution of Alcohols Through the Use of Solketal
type: scientific_journal_article
user_id: '83781'
volume: 16
year: '2023'
...
---
_id: '12836'
abstract:
- lang: eng
  text: The complexity of biodiesel aging has shown that the mechanism needs further
    research. The rate of aging product formation and associated interactions can
    help improve fuel quality. Since biodiesel is a multicomponent system and constant
    changes occur in the chemical environment, which interactions yield which products
    must be shown in more detail. Particularly under observation was the correlation
    between peroxides and epoxides. In addition, it is critical that the influence
    and interactions of new drop-in fuel candidates be investigated. In this work,
    the kinetics of the formation of aging products of methyl oleate (C18:1) are studied.
    The aim was to reduce the complexity in order to be able to make more precise
    and detailed statements about the mechanism. Ketones, acids, peroxide, and epoxide
    values were recorded. A distinction is made between pure methyl oleate and mixtures
    with 3 wt% isopropylidene glycerine (solketal). After solketal decomposed in the
    blends, the aging process showed changes. The influence of solketal resulted in
    a higher number of acids and epoxides over time. It implied that peroxides are
    not necessarily the precursor of epoxides. In summary, correlation and solketal’s
    influence showed that a sequence of aging products could be detected.
article_number: '3253'
author:
- first_name: Julian
  full_name: Türck, Julian
  last_name: Türck
- first_name: Fabian
  full_name: Schmitt, Fabian
  last_name: Schmitt
- first_name: Lukas
  full_name: Anthofer, Lukas
  last_name: Anthofer
- first_name: Anne
  full_name: Lichtinger, Anne
  last_name: Lichtinger
- first_name: Ralf
  full_name: Türck, Ralf
  last_name: Türck
- first_name: Wolfgang
  full_name: Ruck, Wolfgang
  last_name: Ruck
- first_name: Jürgen
  full_name: Krahl, Jürgen
  id: '68870'
  last_name: Krahl
citation:
  ama: 'Türck J, Schmitt F, Anthofer L, et al. Oxidation Kinetics of Neat Methyl Oleate
    and as a Blend with Solketal. <i>Energies : open-access journal of related scientific
    research, technology development and studies in policy and management</i>. 2023;16(7).
    doi:<a href="https://doi.org/10.3390/en16073253">10.3390/en16073253</a>'
  apa: 'Türck, J., Schmitt, F., Anthofer, L., Lichtinger, A., Türck, R., Ruck, W.,
    &#38; Krahl, J. (2023). Oxidation Kinetics of Neat Methyl Oleate and as a Blend
    with Solketal. <i>Energies : Open-Access Journal of Related Scientific Research,
    Technology Development and Studies in Policy and Management</i>, <i>16</i>(7),
    Article 3253. <a href="https://doi.org/10.3390/en16073253">https://doi.org/10.3390/en16073253</a>'
  bjps: '<b>Türck J <i>et al.</i></b> (2023) Oxidation Kinetics of Neat Methyl Oleate
    and as a Blend with Solketal. <i>Energies : open-access journal of related scientific
    research, technology development and studies in policy and management</i> <b>16</b>.'
  chicago: 'Türck, Julian, Fabian Schmitt, Lukas Anthofer, Anne Lichtinger, Ralf Türck,
    Wolfgang Ruck, and Jürgen Krahl. “Oxidation Kinetics of Neat Methyl Oleate and
    as a Blend with Solketal.” <i>Energies : Open-Access Journal of Related Scientific
    Research, Technology Development and Studies in Policy and Management</i> 16,
    no. 7 (2023). <a href="https://doi.org/10.3390/en16073253">https://doi.org/10.3390/en16073253</a>.'
  chicago-de: 'Türck, Julian, Fabian Schmitt, Lukas Anthofer, Anne Lichtinger, Ralf
    Türck, Wolfgang Ruck und Jürgen Krahl. 2023. Oxidation Kinetics of Neat Methyl
    Oleate and as a Blend with Solketal. <i>Energies : open-access journal of related
    scientific research, technology development and studies in policy and management</i>
    16, Nr. 7. doi:<a href="https://doi.org/10.3390/en16073253">10.3390/en16073253</a>,
    .'
  din1505-2-1: '<span style="font-variant:small-caps;">Türck, Julian</span> ; <span
    style="font-variant:small-caps;">Schmitt, Fabian</span> ; <span style="font-variant:small-caps;">Anthofer,
    Lukas</span> ; <span style="font-variant:small-caps;">Lichtinger, Anne</span>
    ; <span style="font-variant:small-caps;">Türck, Ralf</span> ; <span style="font-variant:small-caps;">Ruck,
    Wolfgang</span> ; <span style="font-variant:small-caps;">Krahl, Jürgen</span>:
    Oxidation Kinetics of Neat Methyl Oleate and as a Blend with Solketal. In: <i>Energies :
    open-access journal of related scientific research, technology development and
    studies in policy and management</i> Bd. 16. Basel, MDPI AG (2023), Nr. 7'
  havard: 'J. Türck, F. Schmitt, L. Anthofer, A. Lichtinger, R. Türck, W. Ruck, J.
    Krahl, Oxidation Kinetics of Neat Methyl Oleate and as a Blend with Solketal,
    Energies : Open-Access Journal of Related Scientific Research, Technology Development
    and Studies in Policy and Management. 16 (2023).'
  ieee: 'J. Türck <i>et al.</i>, “Oxidation Kinetics of Neat Methyl Oleate and as
    a Blend with Solketal,” <i>Energies : open-access journal of related scientific
    research, technology development and studies in policy and management</i>, vol.
    16, no. 7, Art. no. 3253, 2023, doi: <a href="https://doi.org/10.3390/en16073253">10.3390/en16073253</a>.'
  mla: 'Türck, Julian, et al. “Oxidation Kinetics of Neat Methyl Oleate and as a Blend
    with Solketal.” <i>Energies : Open-Access Journal of Related Scientific Research,
    Technology Development and Studies in Policy and Management</i>, vol. 16, no.
    7, 3253, 2023, <a href="https://doi.org/10.3390/en16073253">https://doi.org/10.3390/en16073253</a>.'
  short: 'J. Türck, F. Schmitt, L. Anthofer, A. Lichtinger, R. Türck, W. Ruck, J.
    Krahl, Energies : Open-Access Journal of Related Scientific Research, Technology
    Development and Studies in Policy and Management 16 (2023).'
  ufg: '<b>Türck, Julian u. a.</b>: Oxidation Kinetics of Neat Methyl Oleate and as
    a Blend with Solketal, in: <i>Energies : open-access journal of related scientific
    research, technology development and studies in policy and management</i> 16 (2023),
    H. 7.'
  van: 'Türck J, Schmitt F, Anthofer L, Lichtinger A, Türck R, Ruck W, et al. Oxidation
    Kinetics of Neat Methyl Oleate and as a Blend with Solketal. Energies : open-access
    journal of related scientific research, technology development and studies in
    policy and management. 2023;16(7).'
date_created: 2025-04-23T08:48:40Z
date_updated: 2025-06-25T13:13:39Z
department:
- _id: DEP1408
doi: 10.3390/en16073253
external_id:
  isi:
  - '000969447200001'
intvolume: '        16'
isi: '1'
issue: '7'
keyword:
- oxidation kinetics
- biodiesel aging
- methyl oleate
- solketal
- alcohol influence
- sequence of aging products
language:
- iso: eng
place: Basel
publication: 'Energies : open-access journal of related scientific research, technology
  development and studies in policy and management'
publication_identifier:
  eissn:
  - 1996-1073
publication_status: published
publisher: MDPI AG
status: public
title: Oxidation Kinetics of Neat Methyl Oleate and as a Blend with Solketal
type: scientific_journal_article
user_id: '83781'
volume: 16
year: '2023'
...