Supplement kit for NANOCOLOR AOX 3
*taxes and shipping not included
Delivery time approx. 5 working days
Supplement kit for NANOCOLOR AOX 3 for the sensitive AOX range (0.01–0.30 mg/L AOX) as well as for higher COD values (required above 50 mg/L COD).
Platform | Accessories |
Shelf life (from production) | 1 Year(s) |
Storage temperature | 15–25 °C / 59–77 °F |
Scope of delivery | 2 x 4 g for 20 tests |
Gross weight (incl. packaging) | 74 g / 0.16 lbs |
Packaging dimensions | 76 x 85 x 42 mm / 2.99 x 3.35 x 1.65 Inch |
Hazardous material | Yes |
What is the meaning of the parameter AOX?
AOX stands for adsorbable organically bound halides and is a parameter used to assess and analyze water, wastewater and sewage sludge. The AOX value indicates the level of organohalogen compounds that are generally not biodegradable. Unlikely to COD or TOC AOX is not a measurement of oxidizability, but rather tracks very specific compounds that are of concern to humans and the environment. AOX is found in almost every industry, including paints, pesticides, and pharmaceuticals, to name a few. Since the amount of naturally occurring AOX is negligible, it is primarily anthropogenic AOX that is released into the environment. The determination of AOX is regulated in DIN ISO 9652, where the analysis is divided into 3 steps:
AOX
- Adsorption on activated carbon or an AOX adsorbing polymer
- Digestion and conversion of adsorbable organically bound halogens to free halides
- Instrumental detection as freehalide and inference of AOX
Adsorption
In the NANOCOLOR AOX test, bound organic halogens are adsorbed on a polymer-impregnated sponge (NANOSORB). The sample is continuously passed over the NANOSORB sponge in a solid phase extraction. Two extraction methods are available:
1. Manual extraction
Please note that the first time you use the NANOCOLOR AOX 3 test (REF 985007) with manual extraction, you will also need the Starter Kit (REF 916111). All consumables and reagents are included in the AOX 3 kit. Manual extraction is particularly useful when the number of samples is small and only the 0.1 - 3.0 mg/L AOX range is of interest. For this purpose, 100 mL of sample solution is added to a beaker. The NANOSORB cartridge is then connected to the adapter included in the starter kit and the 50 mL syringe. Organically bound halogen compounds are adsorbed by 20 uniform wash cycles with the sample solution. Finally, inorganic halides are removed with 100 mL of rinsing solution.
2. Automatic extraktion (Pump set)
If the AOX extraction step is automated using the Pump Kit (REF 916115), please note that for the first determination the Starter Kit (REF 916111) is required in addition to the NANOCOLOR AOX 3 Test Kit (REF 985007). The extraction by means of a pump is particularly suitable when using the lower measuring range of 0.01 - 0.30 mg/L AOX with 1000 mL sample or to automate the extraction step, especially with large sample quantities. Depending on the range to be measured, 1000 mL or 100 mL of sample solution is added to the extraction apparatus and extracted with the pump for 20 minutes. Finally, the NANOSORB cartridge is rinsed with 100 mL of rinsing solution to remove inorganic halides.
Digestion
During digestion, the halides bound to the NANOSORB as AOX are converted to free halides, as in this example, by a strong oxidizing agent such as peroxodisulfate anion and heat:
AOX + S2O82- → Cl- |
The digestion reagent is added to an empty round tube provided in the test kit and mixed well. The NANOSORB can then be added to the cuvette using the tweezers and funnel provided in the starter kit. The sample is heated in a heating block at 120°C for 30 minutes and acidified after cooling. During heating, organic halides are converted and brought into solution.
In the event of high COD loads (Supplement Kit):
At COD levels > 50 mg/L, AOX detection is impaired because the oxidizing power of the reagents used is also consumed by COD. Therefore, a high COD level will result in a lower detection of AOX. The NANOCOLOR Supplement Kit (REF 918072) is specifically designed to counteract higher COD loads. Use of the kit significantly increases the oxidation capacity of the AOX determination. Excess peroxodisulfate is precipitated by the barium nitrate contained in the extension kit, preventing interference with the subsequent halide determination in the next step.
Photometric determination and reaction basis
After selective adsorption of the organic halides on the NANOSORB and successful conversion to free halides during the digestion, the AOX concentration can be determined in the final step by a simple halide detection reaction (here demonstrated with chloride):
6 Cl- + 3 Hg(SCN)2 + Fe(NO3)3 → [Fe(SCN)6]3- + 3 HgCl + 3 NO32- |
A mixture of mercuric (II) thiocyanate and ferric (III) nitrate is used as the indicator in the reaction. The chloride precipitates from the solution as poorly soluble mercuric chloride, while the nitrate is exchanged for thiocyanate on the iron, forming a blood-red complex that can be detected photometrically at 470 nm. Depending on the extraction volume used (100 mL or 1000 mL sample), the AOX value can be determined within the limits of 0.1 - 3.0 mg/L or 0.01 - 0.30 mg/L.
What is included in the NANOCOLOR AOX 03 test kit (REF 985007)?
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20 x NANOSORB cartridges
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2 x 100 mL rinsing solution concentrate for preparing AOX 3 R1 (fill up to 1 L with distilled water)
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1 x tube of NANOFIX R2
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1 × 105 mL AOX 3 R3
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1 × 75 mL AOX 3 R4
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20 x reaction tubes 16 mm OD
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20 x round cells AOX 3
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2 x round cells Chloride R2
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1 x round cell ZERO solution
What is included in the starter set (REF 916111)?
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1 x pair of tweezers
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2 x funnels
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1 x cartridge adapter
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2 x beakers
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2 x glass rods
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1 x bottle (1000 mL)
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2 x syringes (50 mL)
When should the AOX test be carried out using manual extraction?
- When determining the measuring range of 0.1 - 3.0 mg/L AOX (extraction of only 100 mL sample) and when the number of samples is small.
Which articles are required for the first AOX test using manual extraction?
- In addition to the Test Kit, the Starter Kit (REF 916111) is required for the first AOX determination.
When should I use the Pump Set for AOX testing?
- The pump kit is particularly suitable when AOX is to be determined in the range of 0.01 - 0.30 mg/L (extraction of 1000 mL sample) or when the extraction step is to be automated regardless of the measuring range.
What is required for the first AOX test using the pump kit?
- In addition to the test kit, the Starter Kit (REF 916111) and the Pump Kit (REF 916115) are required for the first AOX determination.
When is the Supplement kit required?
- The supplement kit is recommended when the COD value is greater than 50 mg/L. The Supplement kit can be used to determine AOX in samples with COD levels up to 1000 mg/L.
Is the AOX test suitable for measuring AOX in seawater?
- Yes, because the test is performed in 3 steps, no interference from chloride in seawater is expected.
What are the known interferences?
- Vapors of halogenated solvents in the ambient air may cause the AOX result to be overestimated. COD levels above 50 mg/L or prior filtration of the sample may cause underestimates. For COD levels up to approximately 1000 mg/L, use the extension kit (REF 918072).
What pH should the sample be adjusted to?
- At the beginning of the adsorption step the sample should be in the pH range of 3 - 5. If necessary, the pH can be adjusted with nitric acid.
How can samples be preserved?
- If the pH is adjusted to 1-2 with HNO3, the sample can be stored for up to 1 month.
What is included in the pump set (REF 916115)?
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1 x clamp
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1 x boss
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1 x stand
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1 x pump
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1 x storage container (dropping funnel)
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1 x adapter
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1 x Tubes