Hach DR/700 Procedures Manual page 98

COPPER,
continued
Testing zero concentration samples, the limit of detection was 1.7 µg/L
Cu. The limit of detection was calculated as three times the standard
deviation when testing zero concentration samples (adapted from
Analytical Chemistry, 1980, 52, 2242-2249).
INTERFERENCES
The following may interfere when present in concentrations exceeding
those listed below:
Aluminum
Cadmium
Calcium
Chloride
6+
Chromium (Cr )
Cobalt
Fluoride
Iron
Lead
Magnesium
Manganese
Mercury
Molybdenum
Nickel
Potassium
Sodium
Zinc
Chelating agents, such as EDTA, interfere at all levels unless either the
Digesdahl or vigorous digestion (Section I) is performed.
Highly buffered samples or extreme sample pH may exceed the
buffering capacity of the reagents and require sample pretreatment: see
Interferences, pH (Section I)
SUMMARY OF METHOD
The porphyrin method is very sensitive to trace amounts of free copper.
The method is free from most interferences and does not require any
sample extraction or preconcentration. Interferences from other metals
are eliminated by the copper masking reagent. The porphyrin indicator
forms an intense, yellow-colored complex with any free copper present
in sample.
60 mg/L
10 mg/L
1,5000 mg/L
90,000 mg/L
110 mg/L
100 mg/L
30,000 mg/L
6 mg/L
3 mg/L
10,000 mg/L
140 mg/L
3 mg/L
11 mg/L
60 mg/L
60,000 mg/L
90,000 mg/L
9 mg/L
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