ISO 18473-4:2022 PDF

Overview

ISO 18473-4:2022 specifies requirements and test methods for nanoscale titanium dioxide (TiO2) supplied as powder or suspension for photocatalytic applications. Part of the ISO 18473 series on functional pigments and extenders, this standard covers modified nano‑TiO2 (e.g., surface treatment, coating, doping) and defines classification, sampling, marking, test reporting and essential technical limits to ensure consistent performance in photocatalysis.

Key topics and technical requirements

The standard focuses on characterization and conformity testing for photocatalyst TiO2 nanoparticles. Major technical items include:

• Classification and designation

  • Crystal structure: anatase or mainly anatase with low rutile content.
  • Designation may include the median primary particle size (d50).

• Appearance

  • Powder: white or yellowy‑white (yellow possible with certain dopants).

• Essential requirements (examples from Table 1)

  • Median primary particle size (d50): ≤ 100 nm (reported by TEM or suitable method).
  • Specific surface area (BET): ≥ 35 m²/g (ISO 9277).
  • Residue on 45 µm sieve: