Overview
ISO/TS 2610:2022 specifies a laboratory method for the determination of alkanolamines in biomethane using thermal desorption gas chromatography with flame ionization and/or mass spectrometry detection (TD‑GC‑FID/MS). The technical specification targets trace analysis of five common amine contaminants formed or used during biogas upgrading: monoethanolamine (MEA), diglycolamine (DGA), diethanolamine (DEA), N‑methyldiethanolamine (MDEA) and piperazine (PZ). The method supports compliance testing for biomethane intended for grid injection or use as an automotive fuel (e.g., limits referenced in EN 16723).
Key topics and requirements
- Scope and principle: Active sampling of a known biomethane volume onto conditioned sorbent tubes, followed by thermal desorption, cryogenic trapping and GC separation with FID and/or MS detection.
- Target analytes: MEA, DGA, DEA, MDEA and PZ; compound characteristics are provided in Annex A.
- Sampling: Follow ISO 10715 and ISO 16000‑6 guidance; condition sorbent tubes before use and evaluate breakthrough volume. Sample at least three replicate tubes for representative results.
- Calibration and standards: Prepare calibration tubes by spiking conditioned sorbent tubes with methanol solutions of the five amines (suggested spiking levels e.g., 100–4 000 ng). Use high‑purity amine standards and N‑octane internal/reference standard.
- TD‑GC‑MS/FID parameters (examples): desorption 5 min, carrier flow ~30 ml·min‑1, cryo trap min −30 °C, transfer line ~280 °C. Use SIM (single ion monitoring) when using MS; example m/z values are provided for each amine.
- Performance: Validate repeatability, intermediate precision, reproducibility and measurement uncertainty (Eurachem “Fitness for Purpose” guidance and relevant ISO/IEC uncertainty guidance).
Practical applications and users
- Who uses it: Gas analysis laboratories, biomethane producers, biogas upgrading facilities, grid operators, fuel quality auditors, and regulatory/certification bodies.
- Use cases:
- Quality control during biogas upgrading to ensure amine carry‑over is below specification limits (e.g., EN 16723).
- Pre‑injection compliance testing for biomethane injected to natural gas grids or used as compressed natural gas (CNG).
- Forensic or R&D investigations into amine losses, process optimisation, and contamination sources.
- Routine monitoring programs to demonstrate conformity with contractual or regulatory amine thresholds.
Related standards
- ISO 10715 - Natural gas sampling
- ISO 16000‑6 - Thermal desorption on sorbent tubes (VOC methods)
- ISO 19229 - Purity analysis guidance
- EN 16723 - Biomethane specifications (reference for limit values)
Keywords: ISO/TS 2610:2022, biomethane analysis, amines, TD‑GC‑MS, TD‑GC‑FID, monoethanolamine, diethanolamine, piperazine, sorbent tubes, gas quality.