Sulaiman - 26-7-2020 at 02:18
I had 500g of 3A molecular sieves wet with water and ethanol in a 1000ml rbf
and I distilled off most of the ethanol using a water bath.
The flask now has residue stuck to the inner wall near the bottom of the rbf,
a rinse with conc. HCl followed by 12 hours soaking in dilute HCl removed some of the residue,
washing with detergent made no difference.
I do not want to use abrasive methods as the rbf is new and unscratched.
How can I dissolve or dislodge (presumed) aluminosilicates without damaging the rbf - any suggestions ?
unionised - 26-7-2020 at 02:37
Sodium hydroxide solution might remove the residue.
Or you might just consider this flask to have permanent, not very good, anti-bumping granules in it.
[Edited on 26-7-20 by unionised]
Sulaiman - 26-7-2020 at 03:08
I will leave hot KOH (I have no NaOH) as a last resort as it will probably eat some of the rbf along with the aluminosilicate(s).
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D'oh !
I feel dumb now ... the residue came off easily when I just used water, dtergent and a bottle brush.
[Edited on 26-7-2020 by Sulaiman]
draculic acid69 - 30-7-2020 at 00:06
Maybe just a room temperature soak of hydroxide rather than a hot one would be better.i wouldn't leave hydroxide as a last resort it seems to be a
good option. hot hydroxide can be a last resort but it's definitely worth trying at room temperature