I was wondering if anybody knew how to purify Activated Carbon in the lab. It's ash content is about 4% which i know is small but we still need to bring it down further. Dissolving in acids doesn't remove all the residue. any ideas?

without a breakdown of the ashs composition, its a near impossible question to answer.

 

what acid did you use?

I`de opt for either Nitric or Hydrochloric, Sulphuric can make matters worse (esp with Calcium based impurities).

 

a Strong soln of Potassium Hydroxide 1`st would eliminate some of them, and then follow up with your acid treatment, then dry it using UV light.

 

that will cover most organic and inorganic impurities. things like Silicon will be hard to remove without some very nasty chems like hydrofluoric acid.

 

hope that helps a little

Tried with all three acids already and the one that seemed to have the best effect was actually sulphuric. will try the base KOH aswell. cheers