Overview
ISO/TS 23362:2021 - Nanotechnologies - nanostructured porous alumina as catalyst support for vehicle exhaust emission control - specifies the characteristics to be measured for nanostructured porous alumina powder used as catalyst support in gasoline-powered cars and recommends measurement methods. It defines critical characteristics (required measurements) and additional characteristics (recommended by agreement), gives measurement method guidance, and explains reporting needs. The document is focused on material performance and does not cover health, environmental or safety-specific properties.
Key topics and requirements
- Critical characteristics that must be measured and reported:
- Specific surface area (SSA) - measured by gas adsorption (BET); SSA must be reported before and after thermal treatment.
- Specific pore volume - measured by gas adsorption (BJH), reported before and after thermal treatment.
- Pore diameter - calculated from gas adsorption data (BJH).
- Impurity content - measured by ICP-OES / ICP-AES.
- Additional characteristics (recommended):
- Apparent density (funnel method)
- Tap density (cylinder tapping method)
- Particle size (laser diffraction)
- Loss on ignition (incineration and gravimetry)
- Measurement conditions and treatment:
- Samples are sensitive to moisture; storage in a dry environment is recommended for comparability.
- Typical sample preparation: drying (recommended 200–300 °C) prior to SSA measurement.
- Recommended thermal treatment for stability testing: 1 000–1 100 °C for 4–10 h (parameters can be agreed between buyer and seller).
- Reporting: Measured values of critical characteristics shall be provided to buyers during purchase; templates and reporting guidance are included.
Practical applications
- Ensures consistent quality control and traceability of nanostructured porous alumina used as catalyst support in three-way catalytic converters (TWCs) for gasoline vehicles.
- Helps suppliers and purchasers define acceptance criteria for:
- Noble metal dispersion and loading (influenced by SSA and pore volume)
- Thermal stability and service life of catalytic converters
- Minimizing catalyst deactivation from impurities
- Useful for: material manufacturers, catalyst formulators, automotive OEMs, testing and certification laboratories, and procurement/specification teams.
Who should use this standard
- Manufacturers and sellers of porous alumina powders
- Buyers and procurement specialists specifying catalyst supports
- Quality assurance and R&D teams developing TWC materials
- Test laboratories performing material characterization according to standardized methods
Related standards
Key referenced methods include:
Keywords: ISO/TS 23362:2021, nanostructured porous alumina, catalyst support, vehicle exhaust emission control, specific surface area, pore volume, pore diameter, BET, BJH, ICP-OES, three-way catalytic converter.