What should I do if the pH meter electrode bulb is broken?
pH electrode, also known as pH probe, pH sensor, English name pH electrode or pH sensor, is the part of the pH meter that is in contact with the substance to be measured, and is used to measure the electrode potential.
An industrial on-line pH measurement system usually consists of four parts: a pH sensor, namely a pH electrode, a pH transmitter, an electrode sheath, and a cable.
The main reason for the broken glass bulb of the electrode is caused by external forces such as collision and extrusion. The pressure of the electrode bulb is generally ≤0.6MPa. It is common to use the electrode as a stirrer during measurement. During use, the cleaning, drying, and capping processes must be careful, otherwise it is easy to break due to excessive force. After it is broken, this electrode is estimated to be unusable, and the electrode must be re-selected.
How to protect the electrodes at ordinary times?
1. The electrodes should be stored in a dry environment between 10°C and 30°C.
2. When the temperature is lower than -5°C, the electrode may break due to the freezing of the buffer and electrolyte.
3. Due to transportation reasons, when using electrodes, it is necessary to observe whether the sensitive membrane bubble is filled with solution. If there are bubbles in the membrane bubble, the membrane bubble must be gently shaken down a few times (like a thermometer) to make the membrane bubble inside Fill with solution.
4. If the pH electrode is stored in dry conditions, it must be soaked for 24 hours before use, otherwise it will be difficult to calibrate.
5. When the electrode cap is not used, the electrode must be placed in the buffer solution, not in distilled water.
6. Each electrode needs to be calibrated before it can be used with a pH meter. A two-point calibration is required for the pH electrode, and a standard buffer solution (pH6.86, pH4.00 or pH9.18) should be used for calibration.
7. The frequency of calibrating or checking the measuring electrodes depends on different application conditions (the degree of dirt in the application, the deposition of chemical substances, etc.).
If the electrode bulb or diaphragm is blocked or polluted, the following reagents can be used to clean it:
1. Grease and oily substances can be cleaned with surfactants
2. Calcium precipitates and metal hydroxides can be cleaned with 10% dilute hydrochloric acid
3. Sulfide precipitation (such as in the process of sewage treatment) can be cleaned with a mixture of 10% dilute hydrochloric acid and saturated thiourea
4. Protein attachments (such as in the food industry) can be cleaned with a mixture of 10% dilute hydrochloric acid saturated pepsin
5. When the pH electrode with slow response is regenerated, a mixture of 10% HNO3 and NH4F (50g/1) can be used
