# How does activated carbon trap impurities?

I've tried and I've tried to find an answer to this all over the web, but I can't seem to find an in depth explanation.

To the best of my knowledge, activated carbon has a very microporous structure and uses a process called adsorbption to "trap" particles. This isn't very in depth though and I'd like to better understand the process of what's going from a scientific standpoint. How does the carbon/charcoal keep the adsorbed material attached or trapped within the carbon?

• I don't have time right now for a proper answer, but the keywords you're looking for are chemisorption and physisorption. – Todd Minehardt Aug 9 '17 at 3:36
• @Todd Minehardt cheers for this, I'd be grateful though for a proper answer at your nearest convenience. – Charlie Aug 9 '17 at 15:22

Indeed, in charcoal, there is a large number of $\pi$-electrons that can make bonds, in particular. And yes, the porosity is important.