What is the difference between rechargeable and non-rechargeable pH combination electrodes?
The casing of the pH composite electrode has a distinction between plastic and glass. The rechargeable pH composite electrode has a liquid filling hole on the electrode shell. When the external reference solution of the electrode is lost, the liquid filling hole can be opened to replenish the KCl solution. The non-rechargeable pH composite electrode is filled with gel-like KCl, which is not easy to lose and has no liquid filling hole.
The characteristic of the rechargeable pH composite electrode is that the reference solution has a high permeation rate, the liquid junction potential is stable and reproduced, and the measurement accuracy is high. And when the reference electrode is reduced or contaminated, the KCl solution can be replenished or replaced, but the disadvantage is that it is troublesome to use. When the rechargeable pH composite electrode is used, the liquid filling hole should be opened to increase the liquid pressure and accelerate the electrode response. When the dielectric liquid level is 2 cm lower than the liquid filling hole, a new dielectric liquid should be replenished in time.
The non-rechargeable pH composite electrode is characterized by simple maintenance and convenient use, so it is also widely used. However, when used as a laboratory pH electrode, under long-term and continuous use conditions, the KCl concentration at the liquid junction will decrease, which will affect the test accuracy. Therefore, when the non-rechargeable pH composite electrode is not in use, it should be immersed in the electrode soaking solution, so that the electrode performance will be very good in the next test, and some laboratory pH electrodes are not used for long-term and continuous tests. Therefore, this structure The impact on accuracy is relatively small. The industrial pH composite electrode has relatively low requirements for test accuracy, so it is easy to use and becomes the main choice.
