How to clean the electrodes of a pH meter
Because the concentration and impurities of the medium measured by the pH meter electrode vary, it needs to be cleaned thoroughly for future use. In order to maintain the measurement accuracy and activity of the electrode, different analyses will be conducted on the adhesion of different impurities to the electrode membrane surface. There are several cleaning situations for impurities in pH electrode cleaning: 1. General dirt: 3%~5% hydrochloric acid, washed with high-pressure water (<689.476kPa); 2. Oil or grease: Isopropyl ethanol (wear-resistant ethanol), methanol, other solutions that can remove special fats; 3. PH electrode working under alkaline conditions: hydrochloric acid solution with W=5%~10%, sulfuric acid solution with W=3%~7%; Concentrated hydrochloric acid and phosphoric acid mixed solution; 4. PH electrode working under acidic conditions: hot alkaline solution with W=5%~10% (>56 ℃); Hydrochloric acid with W=5%~10%; Hydrofluoric acid with W=2%~3%; 5. Sulfate and carbonate: hydrochloric acid with W=5%~10%; Concentrated hydrochloric acid and phosphoric acid mixed solution; A mixture of sodium sulfite and sodium hydrosulfite; 6. Silicon dioxide or viscous substance: W=2%~% hydrofluoric acid; Due to the extremely fine nature of the pH meter electrode, removing dirt adhered to the electrode requires sufficient patience and the use of appropriate safety devices during the cleaning process. Choosing the appropriate cleaning solution can make this task easier. When cleaning, immerse the electrode in the cleaning solution for at least 5 minutes to allow the cleaning medium to penetrate the dirt. Washing the electrodes twice is an effective method. Firstly, immerse the electrode in an acidic or alkaline solution, and during the soaking process, brush the electrode with a soft tooth brush to remove dirt. Then choose a solvent for cleaning. Finally, rinse the sensor and soak it in clean water or saline solution (KCl). Maintain its activity sensitivity and extend the service life of the electrode
