EN
ZHTest Method: SATRA TM331
The estimation of soluble chrome in leather
June 1999
SCOPE
This method is intended to determine the amount of soluble chromium, trivalent and hexavalent, present in a leather. The method is applicable to all types of leather and is generally not used with other materials.
PRINCIPLE
A ground test specimen of known mass is extracted with a dipotassium hydrogen phosphate / phosphoric acid solution for a predetermined time under an inert gas. The aqueous extract is filtered to remove any insolubles. A portion of the extract is reacted with potassium permanganate to oxidise any chromium (III) to chromium (VI) and then with diphenyl carbazide to form a coloured complex which indicates the presence of soluble chrome. If this test is positive the soluble chrome is then determined quantitatively using a colorimeter or UV/visible spectrophotometer.
REFERENCES
ISO 3696: 1987 - Water for analytical laboratory use - specification and test methods.
HISTORY
First issued June 1999.
AVAILABILITY
This test method is available to members and non-members.
PRICE (ex. VAT)
This price is for a printed copy of the Test Method.
- Members: £75
- Non-members: £215