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Analyser for the pH value in seawater


HydroFIA pH analyzer

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The CONTROS HydroFIA pH is a flow-through system for the determination of the pH value in saline solutions and ideally suited for measurements in seawater. The autonomous pH analyser can be used in the lab or easily integrated into existing automated measuring systems on e.g. voluntary observing ships (VOS).

Operating principle

Basis for the determination is the change of the colour of the indicator m-Cresol purple in dependence of the sample pH value. For each measurement, a small volume of indicator dye is injected into the sample stream of which the pH value is then determined by means of VIS absorption spectrometry.

Measuring the pH value using m-Cresol purple is an absolute measurement method. Combined with the technical implementation, this analyser is calibration-free and therefore suitable for long-term applications. Furthermore, the analyser can be used for monitoring of e.g. short-term biogeochemical processes.

The low reagent consumption makes long deployment times possible with only minimal maintenance requirements. Once the analyser runs out of reagents, the cartridges can be easily exchanged due to their user-friendly design. In addition, the low sample consumption enables the pH determination from small sample volumes.

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