ISO 6101-4:1997 pdf download – Rubber -Determination of metal contentby atomic absorption spectrometry -Part 4: Determination of manganese content.
3 Principle
A test portion is ashed at 550 C ± 25 C in accordance with ISO 247:1990. method A. The ash is dissolved in hydrochloric acid. The solution is aspirated into an atomic absorption spoctronleter and the absorption is measured at a wavelength of 279.5 nm, using a manganese hollow-cathode Lamp as the manganese emission source Any silicates are volatilized by sulfuric arid hydrofluoric acid
NOTE — ISO 6D65:1962, AatyfAcai roaccpc mcthods Flame ernlasion, atomic ebso.piton. and kxn tluoresceoce
— Vocabataiy. defines Ihe spactrnmaftw lerms iad in this part of ISO 6101
4 Reagents
During the analysis. unless otherwise stated, use only reagents of recognized analytical grade and only distilled water rim waler of equivalent purity
4.1 HydrochlorIc acid. p= 1,18 Mgm3.
4.2 Hydrochloric acid, diluted 1 • 2.
Dilute 1 volume of concentrated hydrochloric acid (4 1) with 2 volumes of water.
4.3 Sulfuric acid, p – 1,84 Mgim3.
4.4 Sulfuric acid, diluted 1.3.
Add carefully I volume of concentrated sulfuric acid (4.3) In 3 volumes of water.
4.5 Hydrofluoric acid, p – I • 13 Mg!m3, 38% (rn/rn) to 40% (rn/rn).
4.6 Standard manganese stock solution, containing 1 g of Mn per cubic decimetre, Either use a commercially available standard manganese solution, or prepare as follows
Using electrolytic mangancoc of purity 90,9 %, free the surface of any manganese oxides by placing a few qrrns of the metal in a beaker containing 60 cm3 to 80 cm3 of I + 3 sulfuric acid (4.4) with about 100 cm3 of water. Stir and, slier a tow minutes. decant the acid solubon and pour water into the beaker. Repeat the decantation and washing with water several times. Then place the manganese metal in acetone and stir. Decant the acetone, dty the rrietal in a hot.air oven (5.13). maintained at 100 C ± 5 C. for about 2 mm and allow it tri cool in a
In a 600 cm3 tall.formn beaker, weigh, to the nearest 0.1 mg, 1 g of this purified manganese metal, end dissolve it with 40 cm of 1.3 sulfuric acid solution (4.4) and about 80 cr&J of water. Boil the solution for several minutes, Allow to cool and transfer quantitatively to a 1 000 cm3 one-mark volumetric flask (see 5.5). Dilute to the mark arid mix thoroughly.
1 cm1 of this standard stock solution contains 1 000 ig of Mn.
4.7 Standard manganese solution, containing 10 mg of Mn per cubic decinietre.
Carefully pipette 10cm3 of the standard manganese stock SOlution (4.6) into a 1 000 cm3 one-mark volumetnc flask (see 5.5). dilute to the mark with 1 + 2 hydrochloric sod (4.2) and mix
Prepare this solution on the clay of use.
5 Apparatus
Ordinary lahoratory apparatus, plus the following:
5.1 Atomic absorplion spectrometer, fitted with a burner ted with acetylene and air, compressed to at least
60 kPa and 300 kPa, respectively, and also fitted with a manganese hollow-cathode lamp as the manganese
emission source. the instrument shall be operated in accordance with the manufacturer’s instructions for nptenum
Alternatively, an electrothermal atomization device (graphite furnace) may be used. It shall be operated by a cuitetent person in accordance with the manufacturer’s instructions for optimum performance.
5.2 Balance, accurate to 0,1 mg
5.3 Muffle furnace, capable of being maintained at a temperature of 550 °C ±25 C.
5.4 Glass filter crucible, filter pore size 16 tim to 40 tim (porosity grade P40 — see ISO 4193).
5.5 One-mark volumetric flasks, glass-stoppered, of capacities 50 cm3, 100cm3, 200cm3, 500cm3 and
1 000 cm3, complying with the requirements of ISO 1042, class A.
5.6 Volumetric pipettas. of capacities 5cm3. 10cm3. 20cm3 and 50cm3. complying with the requirements of ISO 648. cLass A.
5.7 ElectrIc hoiplate or heated sand bath.
5.8 Steam bath
5.9 Platinum or borosilicate-glass rod, for use as a stirrer.
5.10 Crucible, of platinum, and of capactty 50cm3 to ISO cm3 depending on the Ieit portion b.Le.
5.11 CrucIble, of silica or borosilicate glass, of capacity 50 cm3 to 150 cm3 depending on the test portion size, complying with the requirements of ISO 1772.
5.12 Ashless filter paper
5.13 Hot-air oven, capable of being maintained at a temperature of 100 °C 5 °C.
6 Sampling
Carry out sampling as follows.
raw rubber in accordance with ISO 1795:
latex: in accordance with ISO 123:
products: to be representative of the whole batch.