2508025 Phosphate Accuvac Reagent Set, 0.02-2.50 mg/L PO₄

Accuvac Reagent Set measures 0.02-2.50 mg/L PO₄ in drinking water, wastewater and seawater. The product uses ascorbic acid method (8048). Each package of the Accuvac Reagent Set may be used for 25 tests and can be evaluated on all Hach spectrophotometers except DR820. Article 2508025 provides fast and reliable results for phosphate measurement with minimal effort.

Before starting analysis:

• Measure the reagent blank value for each reagent lot to ensure accurate results.
• Perform the sample analysis as soon as possible to receive accurate results of the evaluation.

Procedure for PO₄ measurement

Start program 492 P React (PV AV). Prepare the blank cell and sample cell by adding the water, wastewater or seawater sample in AccuVac Ampuls. Close and stir the content of the AccuVac Ampul for 30 seconds. After 2 minutes, evaluate the blank cell using the instrument. Remove the blank cell, insert the sample AccuVac Ampul in the cell holder and push READ. See manual for additional information regarding sample evaluation using colorimeter.

Summary of method

Orthophosphate enters into reaction with molybdate in acid medium producing mixed phosphate/molybdate complex. Ascorbic acid reduces the complex that gives intense molybdenum blue coloration that must be evaluated photometrically.

Sample preparation

The water, wastewater and seawater sample may be stored at or below 6 °C (43 °F) for a maximum of 48 hours.