Rhodium

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:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Qualifier:

according to guideline

Guideline:

other: ISO 9277:2010(E)

Qualifier:

according to guideline

Guideline:

other: AA_LP_814_BET_08

Qualifier:

according to guideline

Guideline:

other: ISO 14488:2007(E)

Qualifier:

according to guideline

Guideline:

other: ISO 13320:2009(E)

Qualifier:

according to guideline

Guideline:

other: SAA_Troken_DISP, SAA LB2000

Principles of method if other than guideline:

The material was analysed according for particle size distribution after dry dispersion and N-BET.

GLP compliance:

no

Type of method:

Laser scattering/diffraction

Type of particle tested:

primary particle

Type of distribution:

volumetric distribution

Percentile:

D10

Mean:

23 µm

Remarks on result:

other: Range; 22 - 23 µm

Percentile:

D50

Mean:

179 µm

Remarks on result:

other: Range; 165 - 190 µm

Percentile:

D90

Mean:

534 µm

Remarks on result:

other: Range; 522 - 548 µm

Specific surface area N-BET = 0.181 +/- 0.003 m²/g. Range = 0.180 +/- 0.001 to 0.183 +/- 0.002 m²/g.

Table 1: N-BET analysis data and percentiles calculated from the particle size distribution for rhodium.

	Analysis 1	Analysis 2	Analysis 3	Average
Specific surface area N-BET (m^2/g)	0.183 ± 0.002	0.180 ± 0.001		0.181 ± 0.003
X10;3 (μm)	22	23	23	23
X50;3 (μm)	165	182	190	179
X90;3 (μm)	532	522	548	534

Conclusions:

The average 10th, 50th and 90th percentile particle sizes for rhodium sponge were 23, 179 and 534 μm, respectively. The specific surface area was determined as 0.181 ± 0.003 m2/g.

Executive summary:

This is a non-GLP experimental study that follows standard test guidelines and is suitable for use for assessing this endpoint. The average 10th, 50th and 90th percentile particle sizes for rhodium sponge were 23, 179 and 534 μm, respectively. The specific surface area was determined as 0.181 ± 0.003 m²/g.

Description of key information

The average 10th, 50th and 90th percentile particle sizes for rhodium sponge were 23, 179 and 534 μm, respectively and for rhodium-mohr (black) were 5.6, 21 and 47 μm, respectively. The specific surface area for rhodium sponge was determined to be 0.181 ± 0.003 m2/g and for rhodium-mohr (black) the value was determined to be 3.61 ± 0.03 m2/g.

Additional information

Potthoff (2012) is a non-GLP experimental study that follows standard test guidelines and is suitable for assessing this endpoint. The average 10th, 50th and 90th percentile particle sizes for rhodium sponge were 23, 179 and 534 μm, respectively and for rhodium-mohr (black) were 5.6, 21 and 47 μm, respectively. The specific surface area for rhodium sponge was determined to be 0.181 ± 0.003 m²/g and for rhodium-mohr (black) the value was determined to be 3.61 ± 0.03 m²/g.

The dustiness of rhodium black and rhodium sponge was tested in a modified Heubach procedure according to the guideline DIN 55992-1:2006 (Selck and Parr 2012). The studies are non-GLP, but follow a standard guideline and are considered to be reliable. The total dustiness of rhodium black was determined to be 514.78 mg/g. The inhalable fraction was 315.68 mg/g, the thoracic fraction was 74.6 mg/g and the respirable fraction was 15.82 mg/g. The Mass Median Aerodynamic Diameter (MMAD) was determined to be 28.1 μm with a geometric standard deviation of 2.2 μm. The total dustiness of rhodium sponge was determined to be 262.66 mg/g. The inhalable fraction was 161.24 mg/g, the thoracic fraction was 34.47 mg/g and the respirable fraction was 4.45 mg/g. The Mass Median Aerodynamic Diameter (MMAD) was determined to be 26.9 μm with a geometric standard deviation of 2.0 μm.