Reaction mass of zinc oxide and zinc peroxide

Particle size distribution (Granulometry)

Link to relevant study record(s)

Reference

Endpoint:

particle size distribution (granulometry)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Principles of method if other than guideline:

Scanning Electron Microscopy, Particle Size Distribution (by laser diffraction)

GLP compliance:

no

Other quality assurance:

other: ISO9001

Type of method:

other: scanning electron microscopy (SEM), laser diffraction

Type of particle tested:

other: primary particle, agglomerate

Type of distribution:

volumetric distribution

Mass median aerodynamic diameter:

161.56 µm

Geometric standard deviation:

8.89

Percentile:

D10

Mean:

3.29 µm

St. dev.:

0.13

Percentile:

D50

Mean:

136.62 µm

St. dev.:

4.39

Percentile:

D90

Mean:

366.37 µm

St. dev.:

22.3

Due to the observed agglomeration of the sample, relatively aggressive conditions were required to analyse the particle size, with a feed pressure of 4bar and a feed rate of 40 mm/s. A bimodal distribution for the sample was observed, reaffirming the data obtained from the SEM analysis that larger agglomerates are dispersed between the smaller primary particles, the peak maximum for the primary particles being at approx. 5 µm.

Executive summary:

The SEM micrographs showed that the test item consists of small primary particles (approx. 5 µm) and larger agglomerates (up to 100 µm), which is consistent with the results obtained in the particle size analysis.

Description of key information

The test item consists of small primary particles (approx. 5 µm) and larger agglomerates (up to 100 µm).