Caldur® DEHA (diethylhydroxylamine) – Colorimetric
DEHA determination (diethylhydroxylamine) in boiler water by color chart (0.05-1.0 mg/l)
Private customers can also find our range in our partner store Ampha-Analyse.
Reagent for Caldur® DEHA (diethylhydroxylamine) – Colorimetric:
See also:
CALDUR® DEHA (Diethylhydroxylamine) test kit – Colorimetric
What is DEHA measured for?
DEHA (diethylhydroxylamine) is a highly effective oxygen binding agent that plays a central role in boiler water treatment and industrial steam generation. As an organic hydrazine substitute, DEHA binds dissolved oxygen in feed water and thus effectively prevents corrosion in steam boilers, pipelines and heat exchangers. Unlike hydrazine, DEHA is not carcinogenic and is therefore the preferred choice for modern boiler systems.
The typical dosage is between 0.1 and 0.5 mg/l DEHA, depending on the oxygen content of the feed water and the specific operating conditions. Regular monitoring of the DEHA concentration is essential to ensure adequate corrosion protection on the one hand and to avoid overdosing on the other. Too low DEHA values lead to insufficient corrosion protection, while too high concentrations are economically inefficient and can affect the pH value of the boiler water.
DEHA reacts with oxygen and forms acetic acid and nitrogen as reaction products. This reaction takes place at low temperatures and is accelerated at higher temperatures, which makes DEHA particularly suitable for low-pressure boilers and hot water systems.
How does the test set work?
The CALDUR® DEHA test set – Colorimetric works according to the proven ferrozine method. DEHA reduces trivalent iron ions (Fe³⁺) to divalent iron ions (Fe²⁺), which then form a violet color complex with the ferrozine reagent. The intensity of the coloration is directly proportional to the DEHA concentration in the water sample.
After adding two reagents to the water sample, a characteristic violet coloration develops within 5 minutes. The measured value is determined by direct color comparison with a 6-stage color chart provided. This colorimetric method enables fast and reliable on-site analysis without the need for expensive laboratory equipment.
Advantages of the CALDUR® test set
- Quick analysis in just 5 minutes
Ideal for daily routine checks in boiler plants and steam generation systems
- High precision in the relevant concentration range (0.05 – 1.0 mg/l)
Perfect for monitoring the optimum DEHA dosage in boiler water
- 100 provisions per set – economical in continuous use
Cost-efficient for regular inspections in power plants and industrial steam systems
- Can be used colorimetrically – no additional devices required
Flexible for simple on-site tests directly on the boiler system
- Easy handling without special equipment
No additional technology required – ideal for operating personnel
- Robust, waterproof plastic housing with hinged lid
Safe transportation and protection of reagents – durable and reliable
Areas of application
Carrying out the measurement:
- Fill water sample into test tube up to the 10 ml mark
- Add 5 drops of reagent A and mix
- Add 5 drops of reagent B and mix
- Wait for 5 minutes reaction time
- Perform color comparison with color chart
Tip for best results
The water sample should be brought to room temperature before the measurement.
If the boiler water is heavily colored, a blank value determination with distilled water is recommended.
Important notes
- Take the sample as fresh as possible and analyze it immediately
- Bring reagents to room temperature before use
- Adhere exactly to the reaction time of 5 minutes
- Avoid direct sunlight during the measurement
- Rinse test tubes thoroughly with distilled water after use
Measuring range
| Measuring level | Description |
|---|---|
| 0.05 mg/l | Very low concentration (light violet) |
| 0.1 mg/l | Low concentration (light violet) |
| 0.25 mg/l | Optimum concentration (violet) |
| 0.5 mg/l | Average concentration (violet) |
| 0.75 mg/l | Elevated concentration (dark violet) |
| 1.0 mg/l | High concentration (dark violet) |
If the color lies between two fields, you can form the mean value
(e.g. between 0.25 and 0.5 mg/l = approx. 0.35-0.4 mg/l).
Number of possible provisions
You can carry out 100 measurements with one CALDUR® DEHA test set.
This refers to the quantity of reagents contained.
Measuring accuracy and reproducibility
Readability: ± 1 color level
Reproducibility: Very good if the application instructions are followed
Interference: Other reducing agents such as Sulfite or hydrazine can influence the result. High concentrations of iron in the sample should be taken into account.
What to do if measured values are out of range?
Measured value > 1.0 mg/l
| Dilution | Procedure | Calculation of the measured value |
|---|---|---|
| 1:1 | 5 ml sample + 5 ml distilled water | Measured value × 2 |
| 1:4 | 2 ml sample + 8 ml distilled water | Measured value × 5 |
Measured value < 0.05 mg/l
Measured value is below the detection limit. This may indicate insufficient DEHA dosing – check the dosing system and increase the dosing quantity if necessary.
Specifications at a glance
Reagents (reagent A, B)
| Property | Value |
|---|---|
| Parameters | DEHA (diethylhydroxylamine, C₄H₁₁NO) |
| Item number | 31-072300 |
| Method | Colorimetric (ferrozine) |
| Measuring principle | Color comparison with 6-stage color chart |
| Measuring range | 0.05 to 1.0 mg/l DEHA |
| Color scale | 6 measuring levels (0.05 / 0.1 / 0.25 / 0.5 / 0.75 / 1.0 mg/l) |
| Duration of analysis | 5 minutes |
| Number of provisions | 100 |
| Packaging | Hinged lid box |
| Packaging size | 103 x 91 x 36 mm |
| weight | approx. 150 g |
| Scope of delivery |
|---|
| 2 reagent bottles (reagent A, B) with detailed labeling |
| 1 test tube with 10 ml scale |
| 1 color card with 6 measuring levels |
| Detailed operating instructions (DE/EN) |
| Safety data sheets for all reagents |
| Robust hinged lid box (103 x 91 x 36 mm) |
Reagent details
| Reagent | Volume | Shelf life | Notes |
|---|---|---|---|
| Reagent A | 15 ml | 48 months (48M) | Ferrozine solution, shake before use |
| Reagent B | 15 ml | 48 months (48M) | Buffer solution, shake before use |
Shelf life: The shelf life starts from the date of manufacture (printed on the bottle).
After opening, the reagents should be used within 12 months.
Store the test kit in a dry, cool place (10-25°C) and away from direct sunlight.
Additional information
| Packaging | Hinged lid box, Refill pack |
|---|
Flyer
Operating instructions
Instructions for use
Instructions for use
Similar articles:
Related products
-
Determination of sulphate in water by precipitation titration (10 mg/l SO₄²- per drop) -
-
