Experience in Practical Application of Ph Electrode
Quickly judge whether the electrode is good
1. Glass electrode: connect it with a known good reference electrode and the converter, test with two standard buffer solutions, read mV and pH respectively, and check whether it is 60mV/pH.
2. Reference electrode: It is matched with another known good reference electrode and connected to the converter, the electrode to be tested is connected to the working electrode terminal (note that the two electrodes must be the same reference system), and the two electrodes are immersed in a buffer at the same time. Solution, through the "zero adjustment" operation, the converter should be able to read a stable 0mV (pH7).
Electrode protection
1. Regular calibration: The electrode should be calibrated regularly during use to ensure the accuracy of the measured value. At the same time, faults can be found in time through status inspection. The calibration cycle depends on the application. The glass electrode is not completely Nernst response, the standard solution pHS used for calibration should be as close as possible to the measurement medium pHX.
2. Periodic activation: After the electrode has been used for a period of time, it should be actively removed for activation, and another set of electrodes should be replaced at the same time. Such rotation can prolong the life, and the replacement cycle should be 1 to 2 months lower than the aging cycle.
3. Long-term immersion will cause the hydrogen function of the glass membrane to decrease due to the dissolution of the soluble part of the glass membrane. Therefore, if the glass electrode is not used for a long time, it is better to wash it and store it dry.
4. For the electrodes that have been activated after aging or poisoning, it is best not to use them in the process conditions with poor medium environment and high detection requirements. They can be used for pH detection of water media, so that the electrodes can be fully utilized. and prolong its service life. When the electrode sensitivity is lower than 25mV/pH, it is not suitable to continue to use.
