Sciencemadness Discussion Board

Making glassware food safe

TheLogos - 24-2-2012 at 22:51

Hey guys, I recently acquired some glassware from a bankrupt lab that I will using for some experimental medicinal chemistry.

Some of the flask has these glittery residue inside the wall. Some pieces are stained with these brown spots and residue. The ones that look clean, I'm just going to assume that something is there that I can't see.

I might be ingesting some of the compounds produced from these glassware, so I want to make sure that its safe, and not contaminated with heavy metals, carcinogens or anything that might fry my testicles/seeds.

I'm thinking of washing it all with some hot soap solution, 3 hr hcl bath and acetone everything. I have sulfuric acid but it's far too valuable to use for washing glassware.

NaOH bath also on everything except fritted funnels. I have no experience preparing pirahna solution nor do I have access to 30% h2o2.

My question is, will this be enough to remove anything that might be problematic? For example, if the previous owner of these glassware had contaminated the fritted funnels with heavy metals like chromate, lead, arsenic, cadmium, etc., or anything toxic like polychlorinated polycyclic, fluorinated salt, alkylating agents, etc.

how would I make sure to remove all this nasty stuff completely?

Thanks for the help.

I realized that the title is misleading. I'm not trying to cook any food with these glasswares, only that I'm uncomfortable with some unknown substance x leftover floating around that might contaminate future reactions and possibly harm my health.

[Edited on 25-2-2012 by TheLogos]

bahamuth - 25-2-2012 at 04:36

Standard cleaning like soaking in sodium silicate/NaOH hot water solution for several days, rub them clean, then clean with something that might remove residual organics (a good solvent or a powerful oxidizing solution) then clean with aqua regia and finally a regular pass through a dishwasher should be good enough. Sometimes the glassware has been used with radioactive substances so I wouldn't ingest something that have been in contact with pre-owned glassware..

Endimion17 - 25-2-2012 at 06:21

If detergent does nothing, try warm acetone, toluene... you can use even gasoline if the gunk is too terrible.
If there are stubborn, but small quantities (smears) of organic residues, try chromic acid bath or few mililiters of hot piranha if you can't prepare chromic acid, but be extremely careful. Full shield, etc.
After that, base bath in ethanol and sodium hydroxide for a day or two. Then hot hydrochloric bath to remove OH<sup>-</sup> from the surface of the glassware.

If you think there might be radioactive contamination, which is unlikely, you should test it using a Geiger counter first.
If the glass itself has become radioactive, which is highly unlikely (experimental medicinal chemistry labs don't really use large flux neutron beams), you should pick that up on a counter after the washing, too.

For things like viruses/bacteria, an initial submerging in warm bleach with some hydrochloric acid added (to release more free chlorine) for an hour is fine enough.

[Edited on 25-2-2012 by Endimion17]

GreenD - 25-2-2012 at 12:44

Do a NaOH reflux for a few hours, that will get rid of most things. Wash with water. Wash with ethanol, wash with toluene. Everything should be gone by then.

TheLogos - 25-2-2012 at 14:30

I have no access to chromic acid, and aqua regia without great effort. I'll just try acetone, toluene, soap, hcl and naoh. Then cross my fingers and hope I don't die from poisoning.
The glassware came from a lab that worked with a lot of fluoro compounds. Now, it has been declared a superfund site.

Panache - 27-2-2012 at 07:41

Quote: Originally posted by bahamuth  
Sometimes the glassware has been used with radioactive substances so I wouldn't ingest something that have been in contact with pre-owned glassware..


Pussy!

If you have a furnance, ten minutes at five hundred degrees does a good job, then watee rinse, base rinse, dilute hcl rinse, dry and.....drop it accidently on the way to the kitchen.

GreenD - 27-2-2012 at 08:16

From my work with tryptamines - ethanol is one of the only good solvents. Naptha / benzene / EtOAc / acid or basic water = smears it around.

Not that I expect every lab to be working with tryptamines but since vodka is cheap and has other uses, I would definitely incorporate that if you're coming up dirty.