Monday 21 February 2011

Lab Mishaps No. 4 - How Not To Clean Your Glassware


Today passed in the lab pretty swimmingly, I got two steps done on one thing I am working on along with the final step of making that precursor I was talking about last week AND the work-up of the N-phenylproline methyl ester I was working on over the weekend. To top this off I managed not to drop anything, break anything and managed to maintain a fairly decent mood throughout the day. All in all, I can’t complain. 

            To top this off, I heard about a particularly unbelievable bout of sheer stupidity over the weekend. Not half an hour had passed after I left on Saturday when this occurred. Firstly, I’ll set the scene. When I have a lot of dirty glassware (normally test-tubes for collecting column fractions) I’ll set up a sonicator full of acetone and methanol and give the tubes a blitz in there to get rid of any residual gunk once I’ve cleaned them in hot water. When a friend of mine (who uses a lot of highly-coloured organometallic stuff) needs to clean sintered glass he soaks them in nitric acid to get rid of the coloured stuff. These are both valid means of achieving nice sparkly glassware. However, what our esteemed colleague did on Saturday was attempt to combine the two methods by putting a heady mix of concentrated nitric acid (horrible stuff) and acetone into a sonic bath and wash her flasks in that. I am assured that it took all of five seconds for her fumehood to fill with thick, brown, toxic, corrosive nitrogen dioxide once the on button was pushed. All you can do in those situations is sit, watch your fumehood until the gas goes away and pray to a higher being that no-one important walks in.

4 comments:

  1. This has happened in our lab before with nitric acid and dirty sinters, our supervisor is convinced that RT acetone is all you need to clean stuff (as we should be doing reactions 'properly' and not get polymer shit on our glassware in the first place).

    piranha mixture is 2:1 conc sulfuric acid/ hydrogen peroxide, it cleans beautifully and makes sinters sparkling white. A final acetone wash is a new level of stupidity, formation of acetone peroxides is facile...

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  2. Agree- piranha mixture is the way to go!

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  3. The news reported (http://www.weartv.com, http://www.pnj.com) that a couple students apparently working on an independent study at the Univ. of West Florida caused an explosion while ceaning up. While details are skimpy, they were using acetone and nitric acid to clean glassware.

    Two students were slightly injured and the science bldg was locked down for a couple hours.

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  4. It is really beautiful and it makes the sinters sparkling clear and white!

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