ave369
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Spill of chromic acid - cleanup
My lab's right now messy, since I'm on meds and everything in my head is somewhat cloudy. Every now and then I make a blunder. Today I spilled a small
amount (10ml) of chromic acid on my lab table. Immediately covered with bicarbonate of soda.
Any further treatments? Maybe use some reducer to convert it to trivalent chromium?
Smells like ammonia....
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Amos
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Sodium sulfite or metabisufite is generally used. If you can wipe everything up, you can also toss the paper towels or whatever you use into a beaker
with some dilute sulfuric acid, and add ethanol until you're satisfied with the color (which should be green to blue, no hint of brown). I also
recycle all of my hexavalent chromium after it has been reduced to make chromium(III) hydroxide, which is a nice thing to have.
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shivam
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Along with the purchase of any hexavalent chromium, purchase of some Sodium sulfite/ metabisulbite is almost crucial ..
Just in case of any mishaps or simply for reducing the Cr(VI) waste..
Use a solution of sulfite/metabisulfite to clean it up (of cource with gloves) or just spray the spilled area with plenty of ethanol or rubbing
alcohol (isopropanol) solution
leave it until it turns green with no visible orange/brown spots
Then simply wipe it away!!
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chloric1
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Quote: Originally posted by ave369  | My lab's right now messy, since I'm on meds and everything in my head is somewhat cloudy. Every now and then I make a blunder. Today I spilled a small
amount (10ml) of chromic acid on my lab table. Immediately covered with bicarbonate of soda.
Any further treatments? Maybe use some reducer to convert it to trivalent chromium? |
I consider chemistry lab experiments no different from welding or using power tools or heavy machinery. Neither of these activities should be done
under the influence or with a “foggy” mind. After you put on your PPE and start handling glassware and chemicals, you should be ready for the
unexpected. The fact you went straight for the hexavalent chromium while having an off day is concerning.
Fellow molecular manipulator
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Keras
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| Quote: Originally posted by ave369 | My lab's right now messy, since I'm on meds and everything in my head is somewhat cloudy. Every now and then I make a blunder. Today I spilled a small
amount (10ml) of chromic acid on my lab table. Immediately covered with bicarbonate of soda.
Any further treatments? Maybe use some reducer to convert it to trivalent chromium? |
Any reducing agent will bring back Cr VI to Cr III, but the spot won’t go away. Actually I’m not certain there’s a way to wipe away Cr III or VI
stain.
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chloric1
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Yeah anything chromium based is intensely colored and be regarded as a permanent dye. This is why I try to work on glass panels or HDPE when I can.
If not then a piece of sacrificial plywood or drywall piece will do nice temporarily
Fellow molecular manipulator
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unionised
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On chromic acid...
https://www.youtube.com/watch?v=wmin5WkOuPw
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chloric1
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Hey everyone! Watch as my lab bench magically burst into flames! Anyone have a fire extinguisher
Fellow molecular manipulator
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unionised
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https://www.youtube.com/watch?v=nm51SnwcTVk
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chornedsnorkack
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| Quote: Originally posted by shivam |
Just in case of any mishaps or simply for reducing the Cr(VI) waste..
Use a solution of sulfite/metabisulfite to clean it up (of cource with gloves) or just spray the spilled area with plenty of ethanol or rubbing
alcohol (isopropanol) solution
leave it until it turns green with no visible orange/brown spots
Then simply wipe it away!! |
Cellulose´s glucose rings are secondary alcohols, too. Does cellulose reduce chromic acid quickly and quantitatively? Wood, of course, includes
lignin, hemicellulose and pectin, all of which incorporate oxidizable alcohol groups.
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woelen
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Cellulose does indeed reduce chromic acid. If you add a solution of CrO3 in water (or an acidified solution of K2Cr2O7) to paper, which easily absorbs
liquids, then the paper first turns orange at the wet spot, but in a few minutes, its color shifts to green, due to formation of trivalent chromium.
the reaction is not instantaneous. Complete reduction of all hexavalent chromium takes tens of minutes, but in the end, the reaction is complete.
[Edited on 4-10-24 by woelen]
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