Chapter 6 Maintenance
www.supmea.com
- 23 -
Chapter 6 Maintenance
1.
The storage of pH glass electrode, short-term: it’s stored at the buffered
solution of pH=4; long-term: it’s stored at the buffered solution of pH=7.
2.
The washing glass electrode physical bulbs of the pH glass electrode
possibly lengthen the response time of the electrode due to contamination.
CCl4 or soap solution can be used to wipe the dirt, then it can be continued
to use after being soaked in the distilled water for a whole night. It can be
soaked for 10~20 minutes by 5% HF solution when the contamination is
serious, then immediately use water to wash clean, finally It’s used after
being soaked in the 0.1mol/L HCl solution for a whole night.
3.
Treatment of glass electrode aging: the aging of glass electrode is related to
the progressive change of the substratum structure. The response of the old
electrode is slow, the membrane resistance is high, and the slope is low.
The external substratum is etched by HF, which can usually improve the
electrode performance. If the internal and external substratum can be
regularly cleaned by this method, the service life of the electrode is almost
unlimited.
4.
The best storage solution for the storage Ag-AgCl electrode of the reference
electrode is saturation KCl solution, the high concentration KCl solution can
prevent the AgCl from being deposited at the solution border and keep the
solution border at the working condition. This method can also be used for
the storage of combined electrode.
5.
The problems of regenerated reference electrode are mostly caused by
the blocking of solution border, which can be solved by the following
methods:
(1) Solution border is soaked: the mixed liquid of 10% saturation KCl
solution and 90% distilled water is heated to 60~70
℃
, the electrode is
soaked for about 5cm, it’s soaked for 20 minutes to 1 hour. This
method can eliminate the crystal at the electrode terminal.
(2) Soaked by ammonia: the stronger NH3.H20 can be used to eliminate
when the solution border is blocked by AgCl. The specific method is to
