ISO 29541:2010

Overview

ISO 29541:2010 - Solid mineral fuels - Determination of total carbon, hydrogen and nitrogen content - Instrumental method specifies an instrumental combustion procedure for the concurrent determination of total carbon (C), hydrogen (H) and nitrogen (N) in coal and coke. The method converts sample C, H and N to CO2, H2O and N/NOx by high-temperature combustion, removes or converts interfering combustion products, reduces NOx to N2 and quantifies the combustion gases by appropriate gas-analysis detectors. The standard has been validated in accordance with ISO 5725 principles for coal.

Key topics and technical requirements

• Principle: Quantitative conversion of C, H and N to gases during combustion and instrumental gas analysis of CO2, H2O and N.
• Sample size & preparation: Typical test portion ≥ 6 mg; general analysis sample prepared to a nominal top size of 212 µm (per ISO sampling/preparation standards).
• Instrument & apparatus: Furnace for high-temperature combustion, gas-treatment for removal/conversion of interferences, detectors for CO2/H2O/N; balance resolution at least 0.1% of test portion.
• Reagents and gases: Use analytical-grade carrier gas (e.g., helium) and oxygen; extra-dry gas recommended for valve operation in some instruments.
• Calibration materials: Examples provided include EDTA, phenylalanine, acetanilide and BBOT; use certificate values if traceable CRMs are supplied, or stoichiometric values for pure compounds (>99.5%).
• Quality control: Blank analyses (nitrogen blank ≤ 1% of instrument nitrogen response for lowest calibration mass), instrument conditioning, calibration verification, and use of certified reference material (CRM) coal as check samples.
• Precision: The standard addresses repeatability and reproducibility limits and gives procedures for checking acceptability of results.

Practical applications and users

• Who uses it: Analytical laboratories, coal and coke producers, quality control and R&D teams, environmental and energy engineers, and regulatory bodies requiring reliable C/H/N content for combustion calculations, energy content estimation and carbon accounting.
• Why use it:
  • Provides a standardized, traceable instrumental method for total C, H, N analysis.
  • Supports engineering calculations for combustion and emissions, fuel specification, and reporting.
  • Enables consistent calibration, verification and interlaboratory comparability.

Related standards (normative and informative)

Standards referenced in ISO 29541 include:

• ISO 687, ISO 11722, ISO 5068-2, ISO 5069-2 (moisture/sample prep)
• ISO 13909-4 / -6, ISO 18283 (sampling/preparation)
• ISO 5725-6 (accuracy and precision)
• ISO 1213-2 (vocabulary)

Keywords: ISO 29541:2010, total carbon hydrogen nitrogen, coal analysis, coke analysis, instrumental combustion, calibration materials, certified reference material, C H N determination.