Chromatography Forum

In our lab, we have a pile of spargers for a Tekmar purge and trap system - those U-shaped vessels with a glass frit at one side of the bend in the U. These are all awaiting cleaning, but the in-house cleaning procedure (involving conc. acids) has been lost in the mists of time through successive redundancies...

Can anyone suggest a tried-and-true procedure for cleaning out these spargers? When I worked in a synthetic lab, I used to clean fritted glass funnels with conc. HCL (I used nitric for a long time until a run-in with some leftover organic residue...), let them sit until all the acid dripped through, then wash with water, organic solvent (e.g. acetone) and then leave in the oven for at least 4 hours. This rarely got rid of the staining, however.

Any ideas most appreciated.

We normally use conc sulfuric acid mixed with a few drops of NoChromix (a Chrome free version of Chromic acid cleaning solution). It will get rid of any organic residue and any minerals too. I fill the large side and use a pipette bulb to force it through the frit to the opposite side, then out into a beaker to use in the next one. Wash with tap water, then soapy water, then tap water and DI water all in the same way until you are certain all the acid is gone.

Best to rinse with Methanol then we put them in a drying oven at about 100C for a while until the methanol is dry. We don't use acetone because it is one of our target analytes and it is more likely to ignite when drying.

We normally use conc sulfuric acid mixed with a few drops of NoChromix (a Chrome free version of Chromic acid cleaning solution). It will get rid of any organic residue and any minerals too. I fill the large side and use a pipette bulb to force it through the frit to the opposite side, then out into a beaker to use in the next one. Wash with tap water, then soapy water, then tap water and DI water all in the same way until you are certain all the acid is gone.

Best to rinse with Methanol then we put them in a drying oven at about 100C for a while until the methanol is dry. We don't use acetone because it is one of our target analytes and it is more likely to ignite when drying.

Thanks for the tip, I'll need to give sulfuric a go. Never used NoChromix before but I might see if I can track it down. Incidentally, I did have a bottle of CrO3 in my store but it leaked and that was a whole level of headache. And of course, wouldn't use acetone for this application (8260) but will do the drying with methanol.

We normally use conc sulfuric acid mixed with a few drops of NoChromix (a Chrome free version of Chromic acid cleaning solution). It will get rid of any organic residue and any minerals too. I fill the large side and use a pipette bulb to force it through the frit to the opposite side, then out into a beaker to use in the next one. Wash with tap water, then soapy water, then tap water and DI water all in the same way until you are certain all the acid is gone.

Best to rinse with Methanol then we put them in a drying oven at about 100C for a while until the methanol is dry. We don't use acetone because it is one of our target analytes and it is more likely to ignite when drying.

Thanks for the tip, I'll need to give sulfuric a go. Never used NoChromix before but I might see if I can track it down. Incidentally, I did have a bottle of CrO3 in my store but it leaked and that was a whole level of headache. And of course, wouldn't use acetone for this application (8260) but will do the drying with methanol.

We always did the trying step but honestly, since you are just going to put water back into it, I don't see the need if it is rinsed well with DI water. Purge a blank to make sure it is clean and it should be ready to go.