ISO 6101-4 pdf download – Rubber – Determination of metal content by atomic absorption spectrometry一 Part 4: Determination of manganese content.
7 Procedure
7.1 Test portion
Weigh, to the nearest 0,1 mg. approximately lOg of milled or Finely cut rubber info an appropriate crucible (5.10 or 5.11). The size of the test portion shall be fudged by pnor knowledge of the approximate amount of manganese present.
7.2 Preparation of test solution
72.1 DestructIon of organic matter
Ash the test portion ii accordance with method A of ISO 247:1990, in the muffle furnace (5.3), maintained at 550 C ±25 C If the ash is black, caused by small amounts of carbon black, stir carefully with the platinum or bomnsilical.glass rod (59) and crinhinuC beating
722 DIssolution of inorganic residue
After asheng. allow the crucible and its contents to cool to ambient temperature. Add 20 cm3 of concentrated hydrochloric acid (4.1). Heat the mixture on the sleam bath (5 b) for at least 10 men, L)o not let the reaction mixture boil. Allow to cool to arrUerit ternperature and transfer the solotlon quantitatively, with the aid of water. to a Sf) r.r& one-mark volumetric flask (see 5.5). If the ash is not totally dISsolved. puceed as Vol lows:
Transfer the solution and the UndLsSntveel ash quantitatively, with the aid of water, to a platinum crucible (5.1O) Add a few drops of concentrated sulfuflc acid (4.3) and 5 cm3 of hydrofluonc acxt (4.5), Heat on the electric holpiate or sand bath (5.7) in a fume cupboard and evaporate to dnjness. while stirring with a platinum rod (511) Repeat thc digestion with the same quantities of sulfunc and hydrufluonc acids two more times.
Allow to cool to ambeent temperature, add 20 cm3 of concentrated hydrochloric acid (4.1), heat for 10 mm and transfer quantitatively, with the aid of water, to a 50 cm3 one.mark volumetric flask (see 55).
Dilute to the mark with water and mix thoroughly. Insoluble matter may settle and, if so, shall be filtered off using a titter crucible (5.4) rust before making spectrornetric measurements in accordance with 7.3.
Test solutions should contain approximnatety 12% hydrochloric acid. P evaporation. etc.. has reduced or increased this concentration, adjust accordingly with concentrated hydrochloric acid (4.1) or water.
7.3 Preparation of the calibration graph
7.3.1 Preparation of calibration solutions
7.3.1.1 Into a series of five 100cm3 one-mark volumetric flasks (see 5.5) introduce, using pipettes (see 5.6). the volumes of standard manganese solution (4.7) indicated in table 1. Dilute to the mark with I • 2 hydrochloric acid (4.2) and mix thoroughly.
8.3 The test result is the average of two determinahon5. rounded to two decimal places when the manganese (u1)CCr)trdtlvn s expessed as a percentage and to the nearest whole number when the concentration is expessed in milligrams per kilogram.
8.4 Repoil the manganese content as a percentaçe ii qiedlel than or equal to 0.1 %. or in milligrams per kilogiarn ii less than 0.1 %.
9 Test report
The test report shall include the following information:
a) a reference lo this pert of ISO 6101,
b) all details nec.ssary for the comptete dentification of the product tested;
C) the method of samphng.
d) the type of iftstrumpnt used (tiame or graphite furnace spectrometer):
e) the results obtained and the units in which they have been expressed;
f) any unusual features noted dunng the determination:
g) any operation not indudcd in this part of ISO 6101. or in thc Intomationol Standarda to which refcrcncc s made, as well as any incident which might have affected the results.
ISO 6101-4 pdf download – Rubber – Determination of metal content by atomic absorption spectrometry一 Part 4: Determination of manganese content
