MACHEREY-NAGEL NANOCOLOR Advance Guia De Inicio Rapido página 138

NANOCOLOR COD 160
®
Overview
The test is suitable for the photometric determination of the chemi-
cal oxygen demand (COD). The test is in accordance with DIN ISO
15705–H45 and is equivalent to EPA Standard Method 5220 D.
This test is suitable for water, wastewater and sludge.
• Measuring range: 15–160 mg/L O (method 0261)
2
• Number of tests: 20
• Wavelength for photometric determination: 436 / 450 nm
• Shelf life: 12 months
• Reaction time: 120 minutes
• Storage temperature: 15–25 °C
• Storage conditions: protected from sunlight, upright.
Method
The organic compounds of a sample are oxidized by heating the
sample in a mixture of sulphuric acid and potassium dichromate.
The chemical oxygen demand (COD) of a water sample is the con-
centration of oxygen that is equivalent to the amount of potassium
dichromate consumed. The change in the potassium dichromate
concentration is determined via the change in absorbance after
digestion.
Interferences
The foreign materials shown here do not interfere with the test up
to the indicated concentrations (in mg/L). The cumulative effect of
different interfering ions has not been tested.
Data in mg/L:
• Cl - : 1500
Important: For samples in which the chloride content is high, shake
the tube to suspend the precipitate prior to adding the sample. If
the chloride content is greater than 1500 mg/L, you must dilute
the sample or use a chloride masking agent (REF 918911). Once it
has reacted in the heating block, the solution must not be cloudy; Sekil 6: Test kit talimatı
turbidity can result in high COD values.
The use of precipitated mercury sulphate will allow the turbidity to
settle.
This method is not suitable for analyzing seawater.
Turbidity leads to lower measured values.
Reagents and accessories
Contents of reagents set:
• 20 test tubes R0
Required devices:
Küvetteki kirleri, nemi temizlemek ve küvet yuvasının kirlenmesini önlemek için
• MACHEREY-NAGEL photometer
• MACHEREY-NAGEL heating block
• Digital piston pipette 1–5 mL (REF 916909) with pipette tips
(REF 916916)
yerlestirmeden önce tüm küveti tüy bırakmayan bir bezle temizleyin.
• Safety bottle for shaking COD tubes (REF 91637)
Standards
• NANOCONTROL COD 160 (REF 92526)
• NANOCONTROL Multistandard Sewage outflow 1 (REF 925011)
Sampling and preparation
Adım 5: Ölçüm yapılması
See DIN EN ISO 5667-3-A 21 and DIN 38409–H41-1.
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MACHEREY-NAGEL GmbH & Co. KG MACHEREY-NAGEL GmbH & Co. KG DE Tel.: +49 24 21 969-0 DE Tel.: +49 24 21 969-0
Neumann-Neander-Str. 6–8 Neumann-Neander-Str. 6–8 CH Tel.: +41 62 388 55 00 sales-ch@mn-net.com CH Tel.: +41 62 388 55 00 sales-ch@mn-net.com
52355 Düren · Germany 52355 Düren · Deutschland FR Tel.: +33 388 68 22 68 sales-fr@mn-net.com FR Tel.: +33 388 68 22 68 sales-fr@mn-net.com
US Tel.: +1 484 821 0984 US Tel.: +1 484 821 0984
Kirli küvetler, küvet yuvasını kirletebilir ve yanlıs ölçüm sonuçlarına yol açabilir.
Sekil 7: Test tüpü ölçümü
Alternatif olarak, istenen yöntem MN-Testler menüsündeki listelerden seçilerek veya ilgili
menüye test numarası girilerek de çagırılınabilir.
Bir yöntem ilk kez çagrıldıgında alt yöntem de otomatik olarak baslar.
1. Alt yöntem (kimyasal form), sonuç ekranındaki "alt yöntem" girisi tıklanarak
degistirilebilir.
Spektrofotometre NANOCOLOR
138
REF: 985026
en
Quality control
The measurement of a blank value and a standard is recommended
before every measuring series as quality control measure.
Quality data:
The following data were determined during production according to
ISO 8466-1 and DIN 38402-A51:
• Number of LOTs: 75
• Standard deviation of the method: ± 1.06 mg/L O
2
• Coefficient of variation of the process: ± 1.28 %
• Confidence interval: ± 2.44 mg/L O
2
Specified data for procedure:
• Sensitivity (absorbance of 0.010 A corresponds to): 2.18 mg/L
O
2
• Accuracy of a measurement value: ± 8.40 mg/L O
2
LOT-specific certificates are available at www.mn‑net.com.
Procedure
1. Open round cell and hold slightly tilted
2. Pipette 2 mL of sample into test tube
3. Seal test tube and shake vigorously (use safety bottle, cuvette
will become hot!).
4. Heat for 2 h at 148 °C or for 30 min at 160 °C
5. Take the tube from the heating block
6. Shake again after 10 min. while still warm
7. Cool to room temperature
8. Clean outside of test tube
9. Measure
Notes
Test a sample of COD-free water (REF 918993) to generate a blank
value for the reagent.
When using a standard, the measured value is constant over a
period of min. 30 min.
Correction value e. g. for colored or turbid samples possible (see
photometer manual).
When using other photometers, make sure measurements are
possible in test tubes (16 mm OD) and calibrate the method.
Information regarding safety can be found on the box' label
and in the safety data sheet. You can download the SDS from
www.mn‑net.com/SDS.
10/2020
info@mn-net.com info@mn-net.com
sales-us@mn-net.com sales-us@mn-net.com
Testi, ilgili test kitinin talimatlarına göre gerçek‑
lestirin (Sekil 6). Dogru ve güvenilir sonuçlar
elde etmek için talimatı dikkatlice okuyun.
Numuneyi talimatlara göre hazırlayın.
NOT
NOT
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Test tüpleri: Barkodlu tüpü küvet yuvasına
yerlestirin. Barkod otomatik olarak kiti tanınır
ve okur (Sekil 7). For test kits without zero
measurement the result is displayed automa‑
tically after a few seconds.
Sıfırlama ölçümlü bir test kiti kullanırken, cihaz
önce sizden sıfırlama ölçümü yapmanızı ister.
Sıfırlama ölçümü
Daha sonra numune yerlestirilir ve
basılarak ölçüm yapılır.
NOT
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tusuna basılarak yapılır.
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