Sciencemadness Discussion Board

Using charcoal

MXG - 9-4-2013 at 03:06

Is there a rule of thumb for the use of charcoal (and celite)? I often read of using this method to "remove colored contaminants." But then the product in the filtrate is colored yet it was not removed. Is there a rule of thumb for what will be removed by charcoal?
Or is this just a "try it and see" tool?

Thank-you!

Boffis - 9-4-2013 at 05:31

When I use decolourising charcoal I usually work on 0.5 to 1% of the anticipated yield as a crude rule-of-thumb, adjusting the amount to match the degree of coloured impurities I think I have (highly subjective I know). Too much charcoal reduces yields so it better to repeat the process several times if you haven't added enough than add too much and end up with nothing.