Determination of total silicon content in biomethane: Development of a validation approach for ISO 2613-1, as a practical application of the ISO guide under preparation: Biomethane – Performance evaluation for analytical systems

Authors

  • Katarina Hafner-Vuk Institute of Metrology of Bosnia and Herzegovina (BiH)
  • Milica Krajišnik Institute of Metrology of Bosnia and Herzegovina
  • Karine Arrhenius Research Institutes of Sweden (RISE)
  • Sandra Hultmark Research Institutes of Sweden (RISE)
  • Lucy Culleton National Physical Laboratory (NPL)
  • Jianrong Li Van Swinden Laboratorium B.V. (VSL)
  • Jan Beranek Cesky metrologicky institut (CMI)
  • Judit Fűkő Government Office of the Capital City Budapest (BFKH)
  • Tanil Tarhan TUBITAK National Metrology Institute (UME)

DOI:

https://doi.org/10.21014/actaimeko.v14i4.2204

Keywords:

total silicon, biomethane, atomic emission spectroscopy, validation, measurement uncertainty

Abstract

This study presents a validation protocol for the atomic emission spectroscopy (AES) method for determining total silicon in biomethane, developed in alignment with ISO 2613-1:2023. The work serves as a practical demonstration, contributing to the forthcoming ISO validation guide for analytical methods assessing impurities in biomethane, prepared within ISO/TC 193 WG 25: Biomethane. The protocol describes the complete analytical process: absorption of volatile siloxane compounds in mineral acid, chemical derivatization into a suitable form for spectroscopy, and measurement of the resulting liquid sample using an optical plasma emission instrument. Method development included optimisation of sampling, derivatization, sample preparation, and quality control procedures. Validation was carried out through rigorous evaluation of linearity, stability, robustness, selectivity, sensitivity, precision, bias, and measurement uncertainty. Results confirmed the method’s reliability for detecting very low mass fractions of silicon (μg/kg range) originating from siloxane species, such as L2, L3, D4, and D5, in biomethane. By demonstrating both methodological robustness and practical applicability, this study provides a model example for ISO’s upcoming guidance on validation of analytical methods, supporting the harmonisation of impurity testing in renewable gases.

Downloads

Published

2025-12-10

Issue

Vol. 14 No. 4 (2025)

Section

Research Papers

License

Copyright (c) 2025 Katarina Hafner-Vuk, Milica Krajišnik, Karine Arrhenius, Sandra Hultmark, Lucy Culleton, Jianrong Li, Jan Beranek, Judit Fűkő, Tanil Tarhan

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under the CC BY 4.0, Creative Commons Attribution 4.0 International License.

Users are free to

  • share, i.e. copy and redistribute the material in any medium or format for any purpose, even commercially;
  • adapt, i.e. remix, transform, and build upon the material for any purpose, even commercially.

At the same time, the user must give appropriate credit, provide a link to the license, and indicate if changes were made.
Additional information about the license can be found at: https://creativecommons.org/licenses/by/4.0/.

Authors are

  • able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
  • permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).