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Product literature - Brochure |
| The IDRONAUT NITRATE SENSOR is the only Ion Selective Electrode (ISE) able to operate at up to 200 bar pressure because its membrane cap is provided with a unique pressure compensation system which protects and avoids the breakage and stressing of the measuring membrane. The IDRONAUT NITRATE SENSOR belongs to the family of LIQUID MEMBRANE ION SENSITIVE ELECTRODES. The active membrane of this electrode consists of an organic solvent which contains the ion exchanger. The ion exchanger is incorporated in a special PVC membrane, which is glued on top of the screwed membrane cap. The membrane cap must be filled with the special nitrate electrolyte (KNO3 0.01M + KCl 0.01M) and tightened on the sensor body. MEASURING SPECIFICATIONS AND INTERFERENCES Measuring range : 0 to 100 mg/l-N All nitrate ISEs suffer interferences from other ions, especially chloride, bromide, bicarbonate, perchlorate and chlorate. Even though the sensor is most selective to nitrate, other ions, when found in high concentrations, can dominate the sensor response. For example, concentrations of 250 mg/l of chloride ion, 115 mg/l of bromide ion, 40 mg/l of bicarbonate, or 0.3-0.4 mg/l of chlorate or perchlorate ion all "look like" about 1 mg/l-N of nitrate ion to a nitrate ISE. Significant interferences are not likely to be encountered in water with conductivity below 1.000 μS, but in sea water, which contains over 18.000 mg/l of chloride ion, a nitrate sensor would read over 70 mg/l-N for nitrate concentration, even in the absence of nitrate, because of the sodium interference. Because of the chloride ion interference, the nitrate sensor performs poorly in salt water.  |