Reference
117
Solvent reclamation unit SR-305
Question
Answer
When solvent is passed
through new activated
carbon, heat generation
occurs and almost no
solvent can be collected.
What should I do?
When using new activated carbon, reclaim 300 mL of used solvent in advance.
This solvent will almost completely disappear due to adsorption by the activated carbon
surface and heat generation.
Let the activated carbon tank cool to room temperature. Solvent reclamation will now be
possible.
Is the heat generated by
activated carbon
dangerous?
As long as there is good ventilation, it is not dangerous. However, take care not to
directly inhale vaporized solvent.
Activated carbon generates heat up to a temperature of 70°C, however, it cools in
approx. 30 minutes.
How long does reclamation
take?
For example, it may take from 30 minutes to 45 minutes to reclaim 500 mL of solvent.
Is it necessary to measure
the oil content concentration
of reclaimed solvent?
Yes. As a guideline, make sure the concentration is 5 mg/L or less.
The removal efficiency of some oil types is poor, and in some cases 5 mg/L or less
cannot be attained.
In this event, repeat reclamation 2 or 3 times, and make sure the concentration is
constant.
A negative value is shown
for the oil content
concentration of reclaimed
solvent. Can this solvent be
used?
Yes. Perform calibration using zero liquid and span liquid prepared with that reclaimed
solvent, and accurate measurement will be possible.
The oil content concentration of reclaimed solvent is often 0 mg/L or less.
The flow speed of the
solvent is slow. What should
I do?
The water separation tank filter may be clogged. Discard water that has collected in the
separation layer, and replace the water separation filter if dirty.
If the flow speed does not improve after the above measures, replace the activated
carbon and activated alumina.
You should normally be able to collect solvent at a rate of 11 mL/min to 17 mL/min.
What is the role of activated
alumina in the reclamation
unit?
It removes high-polarity compounds (hydrophilic compounds).
This improves the separation conditions when oil content is extracted from water.
Can activated carbon that
has been used to reclaim H-
997 be used to reclaim S-
316?
No. Oil content and dirt adsorbed when the H-997 was reclaimed may dissolve into the
S-316.
Before reclaiming S-316, always replace with new activated carbon and new activated
alumina.
How should the reclamation
unit be stored?
Remove the activated carbon, move the solvent to a glass container with a lid (a screw-
top bottle is recommended) or other airtight container to prevent solvent volatilization,
and store in a cool dark location.
After using a reclamation
unit, I left it without following
the storage procedure. Can I
still use it?
Yes. However, if left for more than 1 week, the activated carbon will dry out, and thus the
first approx. 200 mL of solvent that is passed through the unit will be adsorbed by the
surface of the activated charcoal (heat generation will not occur). The oil content removal
ability will remain the same as previously.
If used solvent has been
saved, at what point should
it be reclaimed?
It is recommended that you collect as much used solvent as possible and reclaim it in
one batch.
Each time reclamation is performed, the amount of solvent reclaimed decreases due to
adsorption by the dried activated carbon, and thus reclaiming in small batches results in
a poorer reclamation rate.
For example, approx. 2400 mL of reclaimed solvent can be obtained from 3300 mL
(approx. 5 bottles) of used solvent (reclamation rate: approx. 73%), whereas approx. 350
mL of reclaimed solvent can be obtained from 645 mL (approx. 1 bottle) of used solvent
(reclamation rate: 54%).