C3 iodine number, C4 hazen colour number (apha-method) – ALTANA LCM plus User Manual
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LCM plus
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C3
Iodine Number
DIN 6162 defines the Iodine colour number as mg of iodine per 100ml of potassium iodide solution.
Colour matching by the Iodine number serves to judge the shade depth of clear liquids like e.g.
tensides, plasticizers, resins, oils and fatty acids, whose colours resemble that of an equally
layered solution of potassium iodide. For Iodine numbers less than or about 1, the Hazen number
according to DIN-ISO 6271 should be preferred.
8
Sampling and preparation are described in
chapter B6. A satisfactory precision of the Iodine value is achieved with a 11mm round glass
cuvette.
Measuring procedure
2.
Fill the sample liquid into a cuvette and insert it into the
corresponding compartment. Measurement starts auto-
matically.
4.
After the measurement, the colour value is indicated on the
display.
5.
Now press the
-key (DIM) until the Iodine number appears on the display.
C4
Hazen Colour Number
(APHA-Method)
The Hazen colour number (DIN-ISO 6271, also known as "APHA-Method” or “Platinum-Cobalt-
scale”) is defined as mg of platinum per 1l of solution. The Hazen parent solution is composed of
1.246g potassium-hexachloroplatinate (IV) and 1.00g cobaltous (II)-chloride dissolved in 100ml of
hydrochloric acid and filled up with distilled water until reaching 1000ml. The Hazen colour scale
serves to determine the colours of nearly water-clear products. It has a narrower gradation in the
light yellow range than the Iodine scale and reaches even water-clear casts.
Attention:
Samples with Hazen values between 50 and 1000 can be measured with sufficient
accuracy in 11mm round cuvettes.
Hazen values < 50 should be mesured in 50mm cuvettes,
Hazen values < 10 should be measured with the cuvette which was used for calibration,
because nearly water-clear products are susceptible to giving faulty measuring results
due to cuvette tolerances.
8
acc. to DIN 6162, Edition 12.81, para. 1
70.5
iodine color value
_DIM ¢Conf 11°