REGENERATION
The moisture sensitive indicator in this self-indicating silica gel changes colour
from orange to a very pale yellow as the crystals/beads adsorb moisture.
The desiccant will adsorb up to one third of it's own weight in moisture before
becoming exhausted. There will still be a little capacity remaining when the pale
yellow colour has been reached but this is a good visual indication that the silica gel
needs replacing or regenerating. Regeneration (reactivation) can be carried out by
heating the silica gel to a temperature between 120 - 150oC until the original colour
has returned. A domestic oven can be used for this purpose.
When regenerated, allow the silica gel to cool slightly (encourage the moisture that
has been driven off to disperse – to prevent it from being immediately re-adsorbed),
before storing in an airtight container until required for further use.
Regeneration can be repeated many times before the crystals/beads become less useful
due to the colour change being no longer apparent. The silica gel will though
continue to adsorb moisture even when the indicator has stopped working.
The ORANGE colour of the crystals/beads changes
to PALE YELLOW (almost colourless) as moisture is adsorbed.
SACHETS
When regenerating self-indicating silica gel sachets, use only the minimum heat required
to return the crystals/beads to their original colour. This will prevent the
sachet material from deteriorating. Regenerating heat-sealed sachets can cause the
seals to fail. If it is known that regeneration is going to be carried out, we can
provide a stitched fabric sachet (the stitching being more robust when heated).
When regenerating, try to place the sachets such that air can circulate around them,
on shelves rather than trays and such that they do not touch the (much hotter) base
or sides of the oven.
STORE IN AN AIRTIGHT CONTAINER WHEN NOT IN USE.