How often is the molecular sieve to be changed?

It is difficult to make a general statement concerning how often the molecular sieve should be replaced, because this is dependent on the humidity in the laboratory. Our experience has shown us that replacement every six weeks is appropriate in the presence of medium humidity. An increase in drift indicates that the leak-tightness of the cell should be inspected and that the molecular sieve should possibly be replaced. Tip: Write the date on which you have last replaced the molecular sieve on the glass of the drying tube. In this way, you will always know when the next replacement is due.

How to regenerate the molecular sieve?

The molecular sieve can be regenerated at 300 °C in the drying oven. The regeneration time is at least 24 hours. The molecular sieve is then placed in a desiccator for cooling down and afterwards stored in a glass bottle with an airtight seal.

KF Titration – Assembling coulometric KF titration cell

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Assemble the coulometer cell as follows:

Place the 6.1903.030 stirring bar in the coulometer cell.
Cut the 6.2713.0x0 ground-joint sleeves to the correct length and attach them to the ground joints of the inserts (electrodes, adsorber tube, etc.). Take care to ensure that the edges of the ground-joint sleeves are cut to size cleanly and that there are no fringes. The ground-joint sleeves must not protrude at the lower edge of the ground-joint opening.
Insert the 6.1403.030 adsorber tube into the generator electrode.
Insert the 6.0345.100 generator electrode without diaphragm or the 6.0344.100 generator electrode with diaphragm together with the adsorber tube into the large ground-joint opening at the rear.
Insert the 6.0341.100 indicator electrode into the left ground-joint opening.
Place the 6.1448.020 septum on the front opening of the coulometer cell and fix it in place with the 6.2701.040 screw cap
Tighten the screw cap only enough so that it seals. The septum must not bend.