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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:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

ISO 13320 (Particle size analysis - Laser diffraction methods)

Deviations:

not specified

GLP compliance:

no

Type of method:

Laser scattering/diffraction

Type of particle tested:

primary particle

Type of distribution:

volumetric distribution

Key result

Percentile:

D10

Mean:

79.9 µm

Remarks on result:

other: not provided

Key result

Percentile:

D50

Mean:

296.3 µm

Remarks on result:

other: not provided

Key result

Percentile:

D90

Mean:

660.9 µm

Remarks on result:

other: not provided

The test item consisted of particles which appeared partially rod-shaped with varying diameters. The particles were introduced to the analyser beam by the dry powder feeder by direct spraying through the measurement area. The powder was loosened by an integrated vibrator. The particles were dispersed and fed to the optical system by pressurized dry air (1,5 bar). After passing the spectrometer the sample was collected in a vacuum cleaner.After adjusting the laser, measuring the background and adjusting the correct particle concentration (obscuration) the measurement was started. The control software automatically performed three measurements. The average of these three measurements was given as result. Two test series of three measurements each were performed. The measurement time was 8s.

The median particle size L50 (50% of particle volume or particle mass with lower particle diameter= deduced from these distributions were:

1^sttest series: 294,2 µm
2^ndtest series: 298,5 µm

The average of the median particle size L50 was: 296,3 µm

The median particle size L10 (10% of particle volume or particle mass with lower particle diameter= deduced from these distributions were:

1^sttest series: 77,8 µm
2^ndtest series: 81,6 µm

The average of the median particle size L10 was: 79,9 µm

The median particle size L90 (90% of particle volume or particle mass with lower particle diameter= deduced from these distributions were:

1^sttest series: 647,3 µm
2^ndtest series: 674,5 µm

The average of the median particle size L50 was: 660,9 µm

The particle size distribution showed a monomodal distribution. The maximum was observed at approximately 300 µm and a shoulder at approximately 10 µm.

Conclusions:

The median particle size L50 of the test item deduced from particle size distributions was 296.3 µm.
The particle size L10 of the test item deduced from the particle size distributions was 79.7 µm.
The particle size L90 of the test item deduced from the particle size distributions was 660.9 µm.

Executive summary:

A study was conducted according to OECD TG 110, OPPTS 830.7520 and ISO 13320 in order to determine the particle size distribution of the test item. The particle size distribution was determined using laser diffraction. Two test series of 3 measurements each were performed with the test item. The median particle size D50 of the test item was determined to be 296.3 µm. The particle size D10 of the test item was determined to be 79.7 µm and the D90 was determined to be 660.9 µm respectively.

Description of key information

The median particle size L50 of the test item deduced from particle size distributions was 296,3 µm.
The particle size L10 of the test item deduced from the particle size distributions was 79,7 µm.
The particle size L90 of the test item deduced from the particle size distributions was 660,9 µm.