Chlorine (with liquid reagents)
Detemination of free chlorine and total chlorine
100086/100087/
100088
Test
Measuring 0.10– 1.00 mg/l Cl
2
50-mm cell
range:
Expression of results also possible in mmol/l and also in free Cl
2
[Cl
2
(f)], combined Cl
2
[Cl
2
(b)], and
total Cl
2
[Cl
2
(t)].
Determination of free chlorine
Add 3 drops of Cl
2
-2,
close with the screw
cap, and mix.
Place 6 drops of Cl
2
-1
into a test tube.
Add 10 ml of the sample
with pipette
, close with
the screw cap, and mix.
Reaction time:
1 minute
Check the pH of the
sample, specified range
:
pH 4 – 8.
If required, add dilute
sodium hydroxide
solution or sulfuric acid
drop by drop to adjust
the pH.
Transfer the solution into
a cell.
Select method with
AutoSelector.
Place the cell into the
cell compartment.
Same preparation as described above, add 2 drops of Cl
2
-3
and
mix after the end of the reaction time
.
A differentiation between free and combined chlorine
[Cl
2
(f)
and Cl
2
(b)] can be performed on the photometer.
Prior to
measuring, select the differentiation measure-
ment and choose the corresponding citation form.
Then measure the free chlorine (result for “free Cl
2
” is
shown on the display), press enter, remove the cell, add
2 drops of Cl
2
-3, mix using the microspatula, and mea-
sure the total chlorine. The individual measuring values
for total and combined chlorine are shown on the dis-
play.
Determination of total chlorine
Quality assurance:
To check the measurement system (test reagents,
measurement device, and handling) a freshly prepared
standard solution
can be used (see section “Standard
solutions”).
Important:
Very high chlorine concentrations in the sample produce
yellow-colored solutions (measurement solution should be
red) and f
alse-low readings are yielded. In such cases the
sample must be diluted (plausibility check).
After each determination of total chlorine rinse the cell
with sulfuric acid 25 % and subsequently several times
with distilled water.
Release 06/2014 - Spectroquant
®
UV/VIS Spectrophotometer Pharo 300