BS ISO 6101-3:2014 pdf free

BS ISO 6101-3:2014 pdf free.Rubber一Determination of metal content by atomic absorption spectrometry
After ashing, 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 steam bath (5.9) for at least 10 min.Do not let the reaction mixture boil. Allow to cool to ambient temperature and transfer the solution quantitatively, with the aid of water, to a 50 cm3 one- mark volumetric flask (5.5). If the ash is not totally dissolved, proceed as follows.
一Transfer the solution and the undissolved ash quantitatively, with the aid of water, to a platinum crucible (5.11). Add a few drops of concentrated sulfuric acid (4.3) and 5 cm3 of hydrofluoric acid (4.5). Heat on the electric hotplate or heated sand bath (5.8) in a fume cupboard and evaporate to dryness, while stirring with a platinum rod (5.10). Repeat this digestion with the same quantities of sulfuric and hydrofluoric acids two more times.
一Allow to cool to ambient temperature, add 20 cm3 of concentrated hydrochloric acid (4.1), heat for 10 min and transfer quantitatively, with the aid of water, to a 50 cm3 one-mark volumetric flask (5.5).
一Dilute to the mark with water and mix thoroughly. Insoluble matter can settle and, if so, shall be filtered off using a filter crucible (5.4) just before making spectrometric measurements in accordance with 7.3.
Test solutions should contain approximately 12 % hydrochloric acid. If evaporation, etc, has reduced or increased this concentration, adjust accordingly with concentrated hydrochloric acid (4.1) or water.Switch on the spectrometer (5.1) sufficiently in advance to ensure stabilization. With the copper hollow-cathode tube suitably positioned, adjust the wavelength to 324,7 nm and the sensitivity and slit aperture according to the characteristics of the instrument.
Adjust the pressures and flow rates of the air and of the acetylene in accordance with the manufacturer’s instructions so as to obtain a clear blue, non-luminous, oxidizing flame, suited to the characteristics of the particular spectrometer being used.
Aspirate the set of calibration solutions in succession into the flame and measure the absorbance of each solution twice, averaging the readings. Take care that the aspiration rate is constant throughout this process. Ensure also that at least one calibration solution is at or below the analyte level found in the rubber being tested.BS ISO 6101-3 pdf free download.