Selenium disulphide

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

Study period:

05/02/2018 to 06/02/2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

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

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

ISO 13320 (Particle size analysis - Laser diffraction methods)

Deviations:

not specified

Principles of method if other than guideline:

The test is also conducted in accordance with CIPAC MT 187 “Particle Size Analysis by Laser Diffraction”, Handbook K, 2007.

GLP compliance:

yes (incl. QA statement)

Type of method:

Laser scattering/diffraction

Type of particle tested:

primary particle

Type of distribution:

counted distribution

Specific details on test material used for the study:

No further details specified in the study report.

Mass median aerodynamic diameter:

> 7.975 - < 8.055 µm

Geometric standard deviation:

1.416

Key result

Percentile:

D50

Mean:

< 5.13 µm

St. dev.:

0.4

Key result

Percentile:

D90

Mean:

< 7.829 µm

St. dev.:

0.4

 Full Test Results

	RUN1	RUN2	RUN3	RUN4	RUN5	Average**
Volume weighted mean	5.402	5.415	5..390	5.373	5.359	5.388
Median	5.142	5.155	5.132	5.116	5.103	5.130
Mode	5.206	5.221	5.198	5.182	5.170	5.195
MMAD*	8.036	8.055	8.020	7.994	7.975	8.016
d10 – 10% of material is <	3.303	3.311	3.299	3.287	3.280	3.296
d50 – 50% of material is <	5.142	5.155	5.132	5.116	5.103	5.130
d90 – 90% of material is <	7.855	7.869	7.831	7.805	7.783	7.829

All result of in μm

*Mass median aerodynamic diameter

**Average result is calculated from the entirety of data captured in each run and is not a simple arithmetic mean.

98.43% by volume of sample was seen to be <10.00 μm

 

Standard Deviation results

Run No.	1	2	3	4	5	STDVP	%STDVP
d10 – 10% of material is <	3.303	3.311	3.299	3.287	3.280	0.011	0.3
d50 – 50% of material is <	5.142	5.155	5.132	5.116	5.103	0.018	0.4
d90 – 90% of material is <	7.855	7.869	7.831	7.805	7.783	0.032	0.4
d15.78 – 15.78% of material is <	3.630	3.640	3.624	3.612	3.604	0.013	0.4
GSD	1.417	1.416	1.416	1.416	1.416	0.000	0.0
MMAD	8.036	8.055	8.020	7.994	7.975	0.029	0.4

GSD = Geometric standard deviation of the lognormal particle size distribution (calculated from d50/d15.78)

STDVP = standard deviation of the population

%STDVP = percentage standard deviation of the population

Conclusions:

Particle Size Analysis using dry powder module (DPM) Average (μm)
Volume weighted mean 5.388
Median (d.50) 5.130
MMAD (Mass Median Aerodynamic Diameter) 8.016
by volume of sample was seen to be < 10.00 μm 98.43 %

Executive summary:

The test is conducted to determine the particle size distribution of Selenium Disulphide. The sample is initially observed to determine whether sieving of the material is required. A method development for the particle size analysis on the material is then undertaken to obtain the correct parameters for the formal analysis. The method development is employed to identify the most appropriate optical properties for the material, the correct dispersant, dispersion pressures and sample compatibility. Once these parameters are obtained the final sample is then analysed using the Malvern Mastersizer 2000 Laser Diffraction Analyser. It is normal practice to complete 5 runs to ensure repeatability of results. The test is conducted in accordance with ISO 13320:2009 “Particle Size Analysis – Laser Diffraction Methods”, 2009 and CIPAC MT 187 “Particle Size Analysis by Laser Diffraction”, Handbook K, 2007.

 

Using the identified parameters, the particle size was analysed over the range 0.02 μm to 2000 μm.

 

Coefficient of variation for d50 is less than 3%; d10 and d90 are less than 5%. Thus repeatability of the characteristic particles in the size distribution are within the acceptable limits as per the ISO 13320-1 test standard.

 

Particle Size Analysis using dry powder module (DPM)	Average (μm)
Volume weighted mean	5.388
Median (d.50)	5.130
Mode	5.195
MMAD (Mass Median Aerodynamic Diameter)	8.016
10 % of material is <	3.296
50 % of material is <	5.130
90 % of material is <	7.829
by volume of sample was seen to be < 10.00 μm	98.43 %

 

The substance is not considered to be potentially inhalable or respirable.

Description of key information

 

Particle Size Analysis using dry powder module (DPM)	Average (μm)
Volume weighted mean	5.388
Median (d.50)	5.130
MMAD (Mass Median Aerodynamic Diameter)	8.016
by volume of sample was seen to be < 10.00 μm	98.43 %

 

Additional information

The test is conducted to determine the particle size distribution of Selenium Disulphide. The sample is initially observed to determine whether sieving of the material is required. A method development for the particle size analysis on the material is then undertaken to obtain the correct parameters for the formal analysis. The method development is employed to identify the most appropriate optical properties for the material, the correct dispersant, dispersion pressures and sample compatibility. Once these parameters are obtained the final sample is then analysed using the Malvern Mastersizer 2000 Laser Diffraction Analyser. It is normal practice to complete 5 runs to ensure repeatability of results.

 

Using the identified parameters, the particle size was analysed over the range 0.02 μm to 2000 μm.

Coefficient of variation for d50 is less than 3%; d10 and d90 are less than 5%. Thus repeatability of the characteristic particles in the size distribution are within the acceptable limits as per the ISO 13320-1 test standard.

 

Particle Size Analysis using dry powder module (DPM)	Average (μm)
Volume weighted mean	5.388
Median (d.50)	5.130
Mode	5.195
MMAD (Mass Median Aerodynamic Diameter)	8.016
10 % of material is <	3.296
50 % of material is <	5.130
90 % of material is <	7.829
by volume of sample was seen to be < 10.00 μm	98.43 %

 

The substance is not considered to be potentially inhalable or respirable.