Sciencemadness Discussion Board

Spill of chromic acid - cleanup

ave369 - 2-12-2015 at 07:17

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?

Amos - 2-12-2015 at 08:22

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.

shivam - 3-12-2015 at 05:44

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!!

chloric1 - 30-9-2024 at 06:06

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.

Keras - 30-9-2024 at 07:53

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.

chloric1 - 30-9-2024 at 09:25

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

unionised - 1-10-2024 at 01:29

Quote: Originally posted by shivam  
or just spray the spilled area with plenty of ethanol or rubbing alcohol (isopropanol) solution

On chromic acid...

https://www.youtube.com/watch?v=wmin5WkOuPw

chloric1 - 3-10-2024 at 03:06

Quote: Originally posted by unionised  
Quote: Originally posted by shivam  
or just spray the spilled area with plenty of ethanol or rubbing alcohol (isopropanol) solution

On chromic acid...

https://www.youtube.com/watch?v=wmin5WkOuPw

Hey everyone! Watch as my lab bench magically burst into flames! Anyone have a fire extinguisher

unionised - 3-10-2024 at 08:30

Quote: Originally posted by chloric1  
Quote: Originally posted by unionised  
Quote: Originally posted by shivam  
or just spray the spilled area with plenty of ethanol or rubbing alcohol (isopropanol) solution

On chromic acid...

https://www.youtube.com/watch?v=wmin5WkOuPw

Hey everyone! Watch as my lab bench magically burst into flames! Anyone have a fire extinguisher

https://www.youtube.com/watch?v=nm51SnwcTVk

chornedsnorkack - 3-10-2024 at 13:48

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.

woelen - 4-10-2024 at 01:42

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]