VISOCOLOR® Iron (Trianzine)
Determination of iron
	Triazine method: iron(II) ions react with a triazine derivative to form a violet complex. Iron(III) ions are reduced and thus also determined. Copper(I) ions interfere forming a grey-violet complex. Nickel ions cause low results. Cobalt ions and molybdate ions interfere forming yellow complex compounds. Nitrite ions interfere because they shift the colour to yellowish-red.

Data and ordering information
Cat. No.	914 239
Type	refill pack
Range	0.1 0.2 0.3 0.5 1.0 2.0 mg/l Fe
Sufficient for	180 determinations
Shelf life	at least 2 years
Sea water suitability	yes
Detectable with PF-11	yes

Natural waters as well as waste waters often contain some iron. It can be present as Fe(II) or Fe(III) ions if the pH value of the water is below 3 or if the water is free of oxygen. At higher pH values Fe(III) forms an insoluble oxyhydrate. Frequently the sample is in a transition state with finely dispersed iron oxides. In waste water and natural water containing humic acids iron is often present in the form of a complex salt. The VISOCOLOR® test kits only determine iron which is present in dissolved form as Fe2+ or Fe3+ ions. Iron complexes are not covered unless they are decomposed by oxidation with nitric acid and sulphuric acid.