Ammonia Sensor
Ion Selective
Hydro-Air Ammonia combination ISE is a traditional pH glass sensor with a refillable membrane cap.
This electrode does not have the solid-state advantage of normal ISE sensor but is able to detect dissolved Ammonia down to around 50ppb. For successful operation NaOH ISAB should be added to the samples and standards to ensure all the Ammonium is converted to NH3.
For process applications addition of ISAB is not usually possible in which case the pH should be above 8.5. In principle the Ammonia penetrates the membrane and causes a change in the pH of the internal solution locally at the interface. This pH change is directly proportional to NH3 concentration.
Malaysia
