LaMotte SMART Spectro Spectrophotometer - Manual (Page 172)

IRON
I,I0-PHENANTHROLINE METHOD • CODE 3668-SC
QUANTITY CONTENTS CODE
15 mL *Acid Phenanthroline Indicator *2776-E
5 g *Iron Reducing Reagent *2777-C
1 Spoon, 0.1 g, plastic 0699
*WARNING: Reagents marked with an * are considered to be potential health
hazards. To view or print a Material Safety Data Sheet (MSDS) for these reagents
go to www.lamotte.com. To obtain a printed copy, contact LaMotte by e-mail,
phone or fax.
Most natural waters contain some iron. Its presence may vary from small traces
to very large amounts in water which is contaminated by acid mine wastes.
For domestic use, the concentration should not exceed 0.2 ppm and for some
industrial applications not even a trace of iron can be tolerated. There are many
means available for removing or reducing the iron content. Water softening resins
are effective for removing small amounts of iron and special ion exchange materials
are selective for iron removal. High concentrations of iron can be removed by such
chemical processes as oxidation and lime or lime-soda softening. Because of the
many means of removing or reducing the amount of iron in water, the particular
method employed will depend largely on the form of iron which is present and the
end use of the treated water.
APPLICATION: Drinking, surface, and saline waters; domestic and
industrial wastes.
RANGE: 0.00–4.50 ppm Iron
MDL: 0.04 ppm
METHOD: Ferric iron is reduced to ferrous iron and subsequently
forms a colored complex with phenanthroline for a
quantitative measure of total iron.
SAMPLE HANDLING
& PRESERVATION
The sample container should be cleaned with acid and
rinsed with deionized water. Addition of acid to adjust
the sample to pH 2–3 will prevent deposition of iron
on the container walls. Samples should be analyzed
as soon as possible after collection since ferrous iron
undergoes oxidation to ferric iron.
INTERFERENCES: Strong oxidizing agents, cyanide, nitrite, and
phosphates, chromium, zinc in concentrations
exceeding 10 times that of iron; cobalt and copper
in excess of 5 mg/L, and nickel in excess of 2 mg/L.
Bismuth, cadmium, mercury, , and silver precipitate
phenanthroline.
SMART Spectro Test Procedures 2.11 IRON, I,I0-Phenanthroline
Test P
rocedures