Overview
ISO 20463:2018 - "Rubber and rubber products - Determination of combustion energy and carbon dioxide emission from biobased and non-biobased materials" defines laboratory methods to measure the combustion energy (gross calorific value) and the carbon dioxide (CO2) emission from biobased and non-biobased components in rubber and rubber products (including polyurethane). The standard covers raw materials, intermediate materials and final rubber products and supports assessment of thermal recycling and alternative-fuel value.
Key topics and requirements
- Scope and purpose: Measurement of gross calorific value and CO2 emission attributable to biobased vs non-biobased carbon in rubber products. Gross calorific value is the primary combustion energy metric specified.
- Sampling: Follow established sampling procedures - ISO 1795 for raw rubber and ISO 4661-2 for vulcanized rubber - to obtain representative test specimens.
- Calorimetric method: Uses a high‑pressure sealed bomb calorimeter (conforming to ISO 1928) with oxygen filling (noted practice: up to 3 MPa) and benzoic acid for calibration.
- CO2 measurement: Collect combustion gas from the bomb, transfer to a gas sampling bag and measure CO2 concentration (e.g., by gas chromatography). Total combustion gas volume, room temperature and atmospheric pressure are recorded for calculations.
- Biobased calculation: Biobased combustion energy and biobased CO2 emission are derived by multiplying measured values by the material’s biobased carbon content (see ISO 19984 series for biobased carbon determination).
- Ancillary requirements: Reagents, apparatus specifications, verification procedures, calculation methods, precision statements and test report content are defined; informative annexes provide examples, net calorific value calculation and precision data.
- Safety and environmental notes: Users must observe normal laboratory safety and appropriate handling/disposal of combustion products and wastes.
Applications and users
ISO 20463:2018 is practical for:
- Rubber manufacturers and compounders assessing fuel value of scrap and product formulations.
- Materials testing laboratories performing calorific and emissions testing for compliance or product data sheets.
- Sustainability and environmental managers quantifying the biobased share of combustion energy and biobased CO2 emissions for reporting, LCA and circular-economy initiatives.
- Waste-to-energy operators and recyclers evaluating rubber waste as alternative fuel and comparing thermal recycling impacts versus fossil feedstocks.
- Product developers optimizing formulations to increase biobased content or reduce net CO2 footprint.
Related standards
- ISO 1928 - bomb calorimetric determination of gross calorific value (solid fuels)
- ISO 19984-2 - determination of biobased carbon content
- ISO 1795, ISO 4661-2 - sampling and sample preparation for rubber testing
- ISO 1382 - rubber vocabulary
Keywords: ISO 20463:2018, rubber products, combustion energy, gross calorific value, carbon dioxide emission, biobased materials, bomb calorimeter, thermal recycling, biobased carbon content.