ISO 8332:2011 pdf free download – Rubber compounding ingredients – Sulfur – Methods of test.
5.3.2 Procedure
Dry one of the sieves specified in 5.3.1.1, or a sieve with openings as agreed between the interested parties, at 80 °C ± 2 °C for 30 mm. Allow it to cool in a desiccator (5.3.1.3) and then weigh it to the nearest 0,1 mg. Repeat this operation until the change in mass is reduced to not more than 1 mg and record the mass of the sieve. From the previously de-agglomerated sample, weigh out, to the nearest 0,1 g, about 10 g (in3) when using a sieve with openings of less than 100 pm or about 30 g (m3) when using a sieve with openings of greater than 100 pm, and transfer to a beaker.
From the test portion, make, in a beaker, a suspension using 100 cm3 or 300 cm3 (depending on the size of the test portion) of a 20 g/dm3 solution of alkylaryl sulfonate in water, pressing it lightly with a glass rod to collapse the lumps. After stirring it sufficiently, pour the suspension onto the screen of the sieve. Shake the sieve gently while pouring in water little by little to allow most of the test portion to pass through it. Then put the sieve into an evaporating dish, fill the dish with water up to a level 10 mm to 15 mm above the screen, and sweep the surface of the screen with a brush (5.3.1.2).
Take the sieve out of the dish, drain out the water from the openings in the sieve, and renew the water in the dish. Repeat this operation until no more of the test portion can be seen in the water in the dish. Wash any solid particles adhering to the brush onto the screen with water, then dry the sieve and contents at 80 °C ± 2 °C for 30 mm. Allow it to cool in a desiccator (5.3.1.3) and then weigh it to the nearest 0,1 mg. Repeat this operation until the change in mass is reduced to not more than 1 mg and record the mass of the sieve and contents. The final mass minus the initial mass of the sieve equals the mass of the sieve residue (m4).
Repeat the procedure with the other sieve specified in 5.3.1.1, or with another sieve with openings as agreed between the interested parties.
5.3.3 Expression of results
Calculate the sieve residue (WrB), expressed as a percentage by mass, using the following formula:
5.3.4 Precision
See B.3.3.
6 Determination of oil content of oil-treated sulfur
6.1 Principle
Oil is extracted from the sample by using a solvent, and the solvent is then evaporated off and the mass of residual oil determined. The residual sulfur is weighed and the amount of oil is calculated.
Two procedures are specified:
a) a procedure using hexane for rhombic sulfur;
b) a procedure using sulfur-saturated hexane for insoluble sulfur.
6.2 Hexane procedure
6.2.1 Reagents
6.2.1.1 Hexane, reagent grade.
6.2.2 Procedure
Weigh, to the nearest I mg, about 10 g of the sample into a wide-mouthed 250 cm3 conical flask and add, by pipette, exactly 100 cm3 of hexane (6.2.1.1). Stopper the flask and allow it to stand at room temperature for 30 mm, swirling the flask every 5 mm. Decant 75 cm3 of the solution thus obtained into a 100 cm3 beaker, ensuring that no particles of sulfur are present. Then pipette 50 cm3 of this solution into another 100 cm3 beaker. Evaporate the solvent from this 50 cm3 of solution by placing the beaker in a water bath in a fume cupboard. Remove the beaker from the water bath and allow it to cool to room temperature. Extract the residue with 2 cm3 of hexane, measuring the solvent from a burette and adding it in such a way that the sides of the beaker are washed down. Swirl the beaker gently to disperse the residue with the solvent. Decant the solution into a 50 cm3 beaker, previously weighed to 1 mg.