Hach 21679-69 DEHA Reagent 1 Powder Pillows
Overview
Hach 21679-69 is a genuine Hach DEHA Reagent 1 Powder Pillow formulation, supplied in packs of 100, used for the determination of oxygen scavengers in boiler feedwater and process water systems by the iron reduction method. Formulated to support Hach Method 8140, the Hach 21679-69 reagent enables plant chemists and water treatment technicians to quantify diethylhydroxylamine (DEHA), carbohydrazide, hydroquinone, iso-ascorbic acid and methylethylketoxime concentrations, giving operators the analytical data needed to verify correct oxygen scavenger dosing in steam and boiler systems.
With engineering support in Muscat, Seven Star LLC supplies Hach 21679-69 DEHA Reagent 1 Powder Pillows on request to industrial plants throughout Oman and the GCC. Every pack shipped from our Muscat-based facility is sourced directly through Hach’s trusted supply channel, ensuring authentic reagent chemistry, correct shelf-life dating and full compatibility with existing Hach spectrophotometers and DR900-series colorimeters already deployed across regional power generation and process water laboratories.
Operating Principle
The Hach 21679-69 DEHA Reagent 1 is the chromogenic half of the two-reagent iron reduction method specified in Hach Method 8140. In the reaction, the oxygen scavenger present in the sample — DEHA, carbohydrazide, hydroquinone, iso-ascorbic acid or methylethylketoxime — reduces the ferric iron supplied by the companion DEHA Reagent 2 Solution to the ferrous state, in an amount equivalent to the scavenger concentration. The indicator chemistry of the Reagent 1 powder pillow then forms a purple complex with that ferrous ion, and the intensity of the purple colour is directly proportional to the oxygen scavenger present, allowing quantification across a working range of approximately 3–450 µg/L DEHA and up to 1000 µg/L for related compounds.
Because the reaction chemistry is standardized and repeatable, results obtained using DEHA Reagent 1 in conjunction with the companion DEHA Reagent 2 solution provide plant chemists with reliable, laboratory-grade quantification without requiring wet chemistry titration setups. This allows boiler water treatment programs to verify oxygen scavenger residuals are maintained within the target range needed to prevent dissolved oxygen corrosion in feedwater heaters, economizers and boiler tubes, protecting capital equipment from premature failure.
Engineering Design of the Hach 21679-69
The reagent is supplied as pre-measured powder pillows, each containing a single-dose quantity of the formulated iron reduction reagent chemistry sealed within a tear-open foil pouch. This single-use format eliminates the measurement error and contamination risk associated with bulk powder handling, ensuring consistent reagent dosing across every test performed by laboratory or field personnel using Hach Method 8140 procedures.
Each pack of 100 powder pillows provides sufficient reagent for 50 complete oxygen scavenger tests when paired with DEHA Reagent 2, supporting sustained testing programs across boiler water treatment monitoring schedules. The reagent is compatible with Hach DR-series spectrophotometers and portable colorimeters commonly deployed in power plant and process water laboratories, integrating directly into existing Hach-based water quality testing programs without requiring additional calibration equipment.
Key Features
The Hach 21679-69 DEHA Reagent 1 Powder Pillow delivers dependable performance around the following capabilities:
- Supports Hach Method 8140 for oxygen scavenger determination by the iron reduction colorimetric method.
- Quantifies DEHA, carbohydrazide, hydroquinone, iso-ascorbic acid and methylethylketoxime concentrations.
- Working range of approximately 3–450 µg/L DEHA supports precise boiler feedwater monitoring.
- Pre-measured single-dose powder pillow format eliminates dosing error and contamination risk.
- Pack of 100 pillows provides reagent for 50 complete tests when paired with DEHA Reagent 2.
- Compatible with Hach DR-series spectrophotometers and portable colorimeters for lab or field testing.
- Genuine Hach chemistry ensures repeatable, laboratory-grade analytical results across testing programs.
- Supports proactive boiler water treatment verification to prevent dissolved oxygen corrosion damage.
Test Procedure, Handling and Interferences
In the published Method 8140 procedure the oxygen scavenger in the sample reduces ferric iron supplied by DEHA Reagent 2 to the ferrous state, and it is the chromogenic chemistry of the Hach 21679-69 powder pillow that then binds that ferrous ion to form a purple complex whose intensity is read at 562 nm on a DR-series spectrophotometer or 560 nm on a colorimeter. One pillow is added to the 25 mL sample and one to the reagent blank — the reason a 100-pillow pack corresponds to 50 complete determinations — followed by 0.5 mL of DEHA Reagent 2 and a reaction period in a dark location of ten minutes, shortened to two minutes when hydroquinone is the scavenger in use.
Method performance depends on disciplined sampling. Samples must be analysed immediately and cannot be preserved: the bottle is filled to overflow and capped at once, agitation and air contact are avoided, and the sample is brought to 25 ± 3 °C (77 ± 5 °F) before the reagents are added. Light exposure during colour development produces a positive bias, which is why the dark reaction period is specified rather than optional. Ferrous iron already present in the feedwater interferes at all levels and must be determined separately and subtracted, while cobalt above 0.025 mg/L, lignosulfonates above 0.05 mg/L and copper above 8.0 mg/L are the interferences most often encountered in treated boiler systems. Unopened Hach 21679-69 pillows should be kept in their original carton, dry and out of direct sunlight, and used within the printed expiry date supplied with each batch.
Industrial Applications
The Hach 21679-69 DEHA Reagent 1 is used extensively in power generation plant chemistry laboratories, industrial steam boiler operations, and process water treatment facilities where oxygen scavenger dosing must be verified to protect high-pressure boiler and feedwater systems from corrosion damage. In Oman’s power generation and desalination sector, as well as petrochemical steam systems across Muscat, Sohar and Salalah, plant chemists rely on DEHA Reagent 1 testing to confirm oxygen scavenger residuals remain within specification across daily and shift-based monitoring routines.
Seven Star LLC supplies 21679-69 reagent packs on request to power plant laboratories, water treatment operators and industrial testing contractors throughout the region, with manufacturer documentation and lead time confirmed at quotation. Facilities across Sohar’s industrial port zone and Salalah’s free trade zone depend on Seven Star LLC for genuine Hach reagent chemistry with full batch traceability.
Technical Specifications
| Parameter | Specification |
|---|---|
| Model | Hach 21679-69 |
| Description | DEHA Reagent 1 Powder Pillows |
| Method | Hach Method 8140, Iron Reduction |
| Quantity | 100 powder pillows per pack (50 tests) |
| Range (DEHA) | 3–450 µg/L |
| Range (Carbohydrazide) | 5–600 µg/L |
| Range (Hydroquinone) | 9–1000 µg/L |
| Range (Iso-ascorbic Acid) | 13–1500 µg/L |
| Range (Methylethylketoxime) | 15–1000 µg/L |
| Wavelength | 562 nm (spectrophotometer) / 560 nm (colorimeter) |
| Sample Volume | 25 mL |
| Reaction Time | 10 minutes in the dark (2 minutes for hydroquinone) |
| Sample Temperature | 25 ± 3 °C (77 ± 5 °F) |
| Sensitivity | 3–14 µg/L per 0.010 Abs change |
| Companion Reagent | DEHA Reagent 2 Solution (Hach 21680-42), 0.5 mL per bottle |
| Compatible Instruments | Hach DR-series spectrophotometers, colorimeters |
Request a Quote for Hach 21679-69 DEHA Reagent 1 Powder Pillows
Seven Star LLC invites plant chemists and procurement teams across Oman and the GCC to submit a formal RFQ for the Hach 21679-69 DEHA Reagent 1 Powder Pillows. Working closely with plant engineers in the region, we supply on request with lead time confirmed at quotation, provide technical datasheets and method sheets on request, and offer direct access to our water analytics division for testing program support. Contact Seven Star LLC today to secure genuine Hach 21679-69 reagent with full manufacturer traceability and regional warranty backing.
Related Products
- Instruction Manual Hach DEHA Oxygen Scavengers Method 8140 Manual Download
Hach analyzers, sensors and reagents listed
The Hach products on this page fall into four groups:- Online analyzers: CL17sc colorimetric chlorine analyzer, TU5300sc and TU5400sc laser turbidimeters, BioTector B3500ul TOC analyzer, Polymetron 9245 sodium analyzer and Orbisphere 510 dissolved gas analyzer
- Controllers and digital sensors: SC4500 controller and the LDO 2 luminescent dissolved oxygen sensor
- Portable and laboratory instruments: 2100Q turbidimeter, HQ4200 multi-parameter meter and IntelliCAL probes such as the LBOD101
- Reagents: DPD free chlorine powder pillows and DEHA reagents for oxygen scavenger testing
Where Hach instruments are used
Hach instruments appear in drinking water plants, desalination, sewage treatment, cooling and boiler water circuits, and industrial effluent monitoring across the GCC. Operators use the portable meters and reagents for spot checks, and the sc analyzers and probes for continuous signals to the control system.Ordering Hach products: what we need
Hach identifies every item by a catalog number, for example LXV416.99.20001 for a sensor or 21055-69 for a reagent pack, and the same reagent may be written with or without the dash. Send that number and the quantity. For analyzers and controllers, add the parameter and range, sample conditions, power supply, outputs and communication option. For sensors, tell us the controller model they will connect to and the cable length. For reagents, name the instrument and method so pack size and range can be confirmed against Hach documentation.Browse Hach products by category: Liquid Analytical Accessories, Liquid Analysis Sensors, Portable Test & Measurement, Liquid Analytical Systems.
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