Hydrogen peroxide – LaMotte DC1600 Colorimeter User Manual
Page 43
HYDROGEN PEROXIDE
DPD METHOD
CODE 3662
QUANTITY
CONTENTS
CODE
30 mL
*Hydrogen Peroxide Reagent #1
*6452-G
100
Hydrogen Peroxide LR Tablets
6454-J
1
Tablet Crusher
0175
*WARNING: Reagents marked with a * are considered hazardous substances. Material Safety Data Sheets (MSDS) are supplied for
these reagents. For your safety, read label and accompanying MSDS before using.
Hydrogen peroxide, H
2
O
2
, is a colorless compound that is widely used as a bleaching or decolorizing agent in the
manufacture of many commercial products. As an oxidizing compound it is also used in the treatment of sewage to reduce
odors and corrosion due to hydrogen sulfide. It may also be used as a sanitizing agent for water treatment. Hydrogen
peroxide is relatively unstable, and for this reason it dissipates quickly and leaves no residuals.
APPLICATION:
Drinking and surface waters; domestic and industrial wastes.
RANGE:
0 – 1.5 ppm Hydrogen Peroxide
METHOD:
Hydrogen peroxide reacts with an excess of potassium iodide through the action of a catalyst
and buffer to release an equivalent amount of iodine. The iodine in turn reacts with
diethyl-p-phenylenediamine (DPD) to produce a pink-red color in proportion to the iodine
released.
SAMPLE HANDLING
& PRESERVATION:
Hydrogen peroxide is not stable in aqueous solutions. Exposure to sunlight and agitation will
accelerate the reduction of hydrogen peroxide in dilute solutions. For best results start analysis
immediately after sampling.
INTERFERENCE:
The likelihood of other oxidizing compounds interfering with this method is eliminated by the
presence of hydrogen peroxide. Manganese may interfere and should be removed before
analysis.
PROCEDURE
1.
Rinse a clean colorimeter tube (0967) with sample water. Fill to the 10 mL line with sample.
2.
Select setting 4 on “Select Wavelength” knob and press “30 Second Read” button.
3.
Insert tube into colorimeter chamber and adjust to 100%T with “Set Blank” knob. This is the 100%T blank.
4.
Remove tube from colorimeter and add 4 drops of *Hydrogen Peroxide Reagent #1 (6452). Cap and mix.
5.
Add one Hydrogen Peroxide LR Tablet (6454). Crush tablet with tablet crusher (0175). Cap and mix until tablet
dissolves. Solution will turn pink if hydrogen peroxide is present. Wait 2 minutes for full color development.
6.
At end of 2 minute waiting period, press “30 Second Read” button and insert tube into colorimeter chamber. Record
%T as soon as reading stabilizes.
7.
Consult calibration chart to determine hydrogen peroxide concentration in parts per million (ppm).
NOTE: It is suggested for the best possible results to carry a reagent blank through the procedure with deionized or
demineralized water. Set the reagent blank to 101%T hydrogen peroxide, then continue with unknown sample tests.
DC1600 HYDROGEN PEROXIDE CALIBRATION CHART
%T
9
8
7
6
5
4
3
2
1
0
90
0.02
0.03
0.03
0.04
0.05
0.05
0.06
0.06
0.07
0.08
80
0.08
0.09
0.10
0.10
0.11
0.12
0.13
0.13
0.14
0.15
70
0.16
0.16
0.17
0.18
0.19
0.19
0.20
0.21
0.22
0.23
60
0.24
0.25
0.26
0.27
0.28
0.28
0.29
0.30
0.31
0.33
50
0.34
0.35
0.36
0.37
0.38
0.39
0.40
0.42
0.43
0.44
40
0.46
0.47
0.48
0.50
0.51
0.53
0.54
0.56
0.57
0.59
30
0.61
0.63
0.64
0.66
0.68
0.70
0.72
0.74
0.77
0.79
20
0.81
0.84
0.86
0.89
0.92
0.95
0.98
1.01
1.05
1.09
10
1.12
1.16
1.21
1.26
1.31
1.36
1.42
1.48
1.55
0
43