English (GB)
27
7.12.2 Measurement
7.13 Iron, 0.02 - 1 mg/l Fe
Determination of total dissolved Iron Fe
2+
and Fe
3+
7.13.1 Important notes
Digestion procedure for the determination of total soluble and
insoluble iron:
1. Add 1 ml of concentrated sulphuric acid to 100 ml water
sample. Heat and boil for 10 minutes or until all particles are
dissolved. After cooling down, the sample is set to a pH-value
of 3 to 5 by using ammonia solution. Refill with deionised
water to the previous volume of 100 ml and mix well. 10 ml of
this pre-treated solution is used for the subsequent analysis.
Perform as described by the selected test method.
2. Water which has been treated with organic compounds like
corrosion inhibitors must be oxidised where necessary to
break down the iron. Therefore add 1 ml concentrated
sulphuric acid and 1 ml concentrated nitric acid to 100 ml
water sample and boil to approx. half volume. After cooling
down, proceed as described above.
7.13.2 Measurement
1. This method determines the total
dissolved Iron as Fe
2+
and Fe
3+
.
2. For the determination of total dissolved and undissolved iron
digestion is required. An example is described in section
7.14 Manganese, 0.2 - 4 mg/l Mn
7.14.1 Important notes
When the result is displayed, the chemical
species can be changed:
Mn
MnO
4
KMnO
4
7.14.2 Measurement
1. Fill a clean vial (
∅
24) with 10 ml of the
water sample. Close tightly with the cap.
2. Place the vial in the sample chamber
correctly. See fig.
3. Press the [Zero] key.
4. Remove the vial from the sample
chamber and empty it, leaving a few
drops in the vial.
5. Add one
Hydrogen peroxide LR
tablet
(No
) straight from the foil and
crush the tablet using a clean stirring
rod.
6. Add water sample to the 10 ml mark.
7. Close the vial tightly with the cap and
swirl gently several times until the tablet
is dissolved.
8. Place the vial in the sample chamber
correctly. See fig.
9. Press the [Test] key. Wait for a reaction
period of 2 minutes.
After the reaction period is finished the
measurement starts automatically.
The result is shown in the display in mg/l
hydrogen peroxide.
T
M
04
16
60
35
10
prepare Zero
press ZERO
∅
24
Countdown
2:00
Zero accepted
prepare Test
press TEST
2
2
0
Iron
determination
Fe
2+
+ Fe
3+
Dissolved iron
Filtration of water
sample
Dissolved and
undissolved iron
Digestion process
Method 220
1. Fill a clean vial (
∅
24) with 10 ml of the
water sample. Close tightly with the cap.
2. Place the vial in the sample chamber
correctly. See fig.
.
3. Press the [Zero] key.
4. Remove the vial from the sample
chamber.
5. Add one
Iron LR
tablet (No
straight from the foil to the 10 ml sample,
and crush the tablet using a clean stirring
rod.
6. Close the vial tightly with the cap and
swirl gently several times until the tablet
is dissolved.
7. Place the vial in the sample chamber
correctly. See fig.
.
8. Press the [Test] key. Wait for a reaction
period of 5 minutes.
After the reaction period is finished, the
measurement starts automatically.
The result is shown in the display in mg/l
iron.
1. Fill a clean vial (
∅
24) with 10 ml of the
water sample, close tightly with the cap.
2. Place the vial in the sample chamber
correctly. See fig.
.
3. Press the [Zero] key.
4. Remove the vial from the sample
chamber.
5. Add one
Manganese LR 1
tablet
(No
) straight from the foil to
the water sample, crush the tablet using
a clean stirring rod, and dissolve the
tablet.
6. Add one
Manganese LR 2
tablet
(No
) straight from the foil to
the same water sample and crush the
tablet using a clean stirring rod.
7. Close the vial tightly with the cap and
swirl gently several times until the tablets
are dissolved.
8. Place the vial in the sample chamber
correctly. See fig.
.
9. Press the [Test] key. Wait for a reaction
period of 5 minutes.
When the reaction period is finished, the
measurement starts automatically.
The result is shown in the display in mg/l
manganese.
2
2
0
prepare Zero
press ZERO
∅
24
Countdown
5:00
Zero accepted
prepare Test
press TEST
2
4
0
prepare Zero
press ZERO
∅
24
Countdown
5:00
Zero accepted
prepare Test
press TEST
Содержание DIT-M
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