LaMotte COD Plus Colorimeter 1922-EX2 - Manual (Page 80)

COPPER
CUPRIZONE METHOD • CODE 4023
QUANTITY CONTENTS CODE
15 mL Copper A
P-6367-E
15 mL *Copper B
P-6368-E
*WARNING: Reagents marked with * are considered hazardous substances. Material
Safety Data Sheets (MSDS) are supplied for these reagents. For your safety, read label
and accompanying MSDS before using.
The copper content of drinking water generally falls below 0.03 parts per
million, but copper levels as high as 1.0 part per million will give water a bitter
taste. Waters testing as high as 1.0 part per million copper have probably been
treated with a copper compound, like those used in the control of algae, or
have become contaminated from untreated industrial wastes. The addition of
copper sulfate to lakes causes an increase in the copper content of the
sediments. Acid waters and those high in free carbon dioxide may cause the
corrosion or “eating away” of copper, brass and bronze pipes and fittings. This
corrosion results in the addition of copper to the water supply.
APPLICATION:
Drinking, surface, and domestic waters. Pools and spas.
RANGE: 0 to 2.0 ppm Copper
METHOD: Copper ions form a blue complex with cuprizone, in a 1 to 2
ratio, at a pH of about 8, in proportion to the concentration
of copper in the sample.
SAMPLE
HANDLING &
PRESERVATION: Copper has a tendency to be adsorbed to the surface of the
sample container. Samples should be analyzed as soon as
possible after collection. If storage is necessary, 0.5 mL of
20% hydrochloric acid per 100 mL of sample will prevent
“plating out”. However, a correction must be made to bring
the reaction into the optimum pH range.
INTERFERENCES: Hg +1 at 1 ppm. Cr +3 , Co +2 , and silicate at 10 ppm. As +3 ,
Bi +3 , Ca +2 , Ce +3 , Ce +4 , Hg +2 , Fe +2 , Mn +2 , Ni +2 and
ascorbate at 100 ppm.
Many other metal cations and inorganic anions at 1000 ppm.
EDTA at all concentrations.
COD PLUS TEST PROCEDURES 6/02 COPPER - DDC 1/2