Sciencemadness Discussion Board

Repurposing glassware

j_sum1 - 30-10-2014 at 05:41

I have come across some broken volumetric pipettes. I hate throwing stuff like that out. Seems like it might make a good ampoule or even better a gas discharge tube.
I would luke to get rid of the things printed on them. No solvents I tried made any impression. But it does not appear to be etched. How are these things printed and any suggestions as to what might move it?

mangoman667 - 30-10-2014 at 06:48

As far as ampoules, they will work great for that purpose. Just make sure you put a nice, thick seal on it to avoid breakage. Other than that, I've heard that some people use broken borosilicate for boiling chips. Maybe just crush some up into smaller pieces so it's easier to insert.

Dr.Bob - 30-10-2014 at 07:37

I have found, by accident, that concentrated sulfuric acid dissolves the printing on some pipettes, especially when mixed with DMSO. BTW, that strips the paint off nearly everything, especially when boiling... But the chemistry works, which is even more amazing.

j_sum1 - 31-10-2014 at 21:07

Conc sulfuric did nothing.

Chemosynthesis - 31-10-2014 at 23:54

Quote: Originally posted by j_sum1  
Conc sulfuric did nothing.
Was it a commercial drain cleaner? Drain cleaners sometimes have buffers.

j_sum1 - 1-11-2014 at 00:47

Nope. LR grade H2SO4 at the school where I work.
I didn't leave it soaking or anything though. Prolonged exposure may be different.

hyfalcon - 1-11-2014 at 04:34

Heat it while soaking. HOT sulfuric has stripped the ink out of engraved marks on one of my thermometers.

HgDinis25 - 1-11-2014 at 05:22

Like some have stated, Sulfuric Acid usually does the trick. Heat it to decomposition temperature for further attack on the ink. You may also consider Piranha Solution, if you have access to concentrated H2O2.

chemrox - 1-11-2014 at 16:27

Piranha is expensive and ephemeral. Try what Dr. Bob suggested. Boiling sulfuric and DMSO... btw, what buffers in acid drain cleaner!? That would be counter-productive. How would you 'buffer' con H2SO4? to pH 0.01?

Little_Ghost_again - 2-11-2014 at 02:51

I use the glass tube bits as stir bars etc, just put some metal rod inside, melt the glass closed then cut.
I was lucky enough to have some broken ones amongst some other stuff, really handy things! I left the paint on though

HgDinis25 - 2-11-2014 at 03:33

Quote: Originally posted by chemrox  
Piranha is expensive and ephemeral. Try what Dr. Bob suggested. Boiling sulfuric and DMSO... btw, what buffers in acid drain cleaner!? That would be counter-productive. How would you 'buffer' con H2SO4? to pH 0.01?


I'm sorry, did you just say that Piranha solution is expensive and went on encouraging the use of DMSO?