MACHEREY-NAGEL NANOCOLOR Advance Mode D'emploi Simplifié page 107

NANOCOLOR COD 160
®
Overview
The test is suitable for the photometric determination of the
chemical 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 concentration
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 following contaminants do not interfere with the test up to the
indicated concentrations. 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; turbidity can result
in suppressed COD values.
Fig. 6: Instrução do kit
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:
• MACHEREY‑NAGEL photometer
• MACHEREY‑NAGEL heating block
Limpe as cubetas com um pano sem fiapos antes da inserção desta no suporte de • Digital piston pipette 1 – 5 mL (REF 916909) with pipette tips
(REF 916916)
• Safety bottle for shaking COD tubes (REF 91637)
Standards
cubeta, afim de remover quaisquer impurezas e/ou umidade da cubeta, evitando sujar o
• NANOCONTROL COD 160 (REF 92526)
• NANOCONTROL Multistandard Sewage outflow 1 (REF 925011)
Sampling and preparation
suporte de cubetas e lentes.
See DIN EN ISO 5667‑3‑A21 and DIN 38409‑H41‑1.
Quality control
The measurement of a blank value and a standard is recommended
before every measuring series as quality control measure.
Step 5: Executar uma medição
MACHEREY-NAGEL GmbH & Co. KG · Valencienner Str. 11 · 52355 Düren · Germany
Tel.: +49 24 21 969-0 · info@mn-net.com · www.mn-net.com
As cuvetes quentes T>80°C podem danificar o reconhecimento da cuvete e
conduzir a resultados de medição incorrectos. Certificar‑se de que as cuvetes
arrefeceram até à temperatura indicada nas instruções antes de efetuar a medição.
As cubetas contaminadas podem contaminar o suporte de cubeta e levar a resultados
de medição incorretos.
Fig. 7: Medição de teste em tubo
Alternativamente, o método desejado pode ser acessado selecionando a partir das listas
no menu Testes MN ou inserindo o número do teste no menu correspondente.
Espectrofotômetro NANOCOLOR
REF: 985026
en
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 mg/L O
2
• Coefficient of variation of the process: ± 1 %
• Confidence interval: ± 2 mg/L O
2
Specified data for procedure:
• Sensitivity (absorbance of 0.010 A corresponds to): 2 mg/L O
2
• Accuracy of a measurement value: ± 5 mg/L O
2
LOT‑specific certificates are available at www.mn-net.com.
Procedure
1. Put the sediment in the reaction cuvette into suspension by swirling
2. Open round cell and hold slightly tilted. 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
In contrast to the conditions described in the ISO 15705, the short time
COD is characterized by a higher digestion temperature and reduced
reaction time. Therefore we recommend to compare the results of the
short time COD from time to time with measurements made under the
conditions of ISO 15705 (150 ± 5 °C / 2 h ± 10 min).
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.
10/2023
Realize o teste de acordo com as instruções
do respectivo kit (Fig. 6). Leia com atenção
para obter resultados precisos e confiá‑
veis. Prepare a amostra de acordo com as
instruções.
AVISO
AVISO
Testes em tubo: insira o tubo com o código
de barras no suporte de cubetas. O código de
barras é reconhecido e lido automaticamente
(Fig. 7). Para kits de teste sem medição do
zero, o resultado é exibido automaticamente
após alguns segundos.
Ao usar um teste com medição do zero, o
dispositivo primeiramente vai solicitar que
você meça a solução zero. A medição do
zero é disparada pressionando
amostra é inserida e é medida pressionando
.
Advance 1.2, 04.2024
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